FRDS Preventive Maintenance Schedule Revised:
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3 47 Overview Due to the hostile environment seen by aerial firefighting equipment, preventive maintenance of the FRDS and related equipment is required to ensure system reliability and maximize the performance of the system. This document provides the recommended preventive maintenance schedule and procedures required for long-term reliability of the FRDS units. In addition to the information presented here, this document refers to SIL s and other support materials. References Item Document Company 1 FRDS - System Maintenance & Troubleshooting Guide Trotter Controls Inc. DRAWINGS 2 Drawing 061E500 "High current power supply" Trotter Controls Inc. 3 Drawing 061P500 "Assembly, PLC Enclosure" Trotter Controls Inc. 4 Drawing 061P501 "Assy, Toshiba computer" Trotter Controls Inc. 5 Drawing 061P531 "Wire Assembly, PLC Enclosure" Trotter Controls Inc. 6 Drawing 061P532 "Wire List, Wire Assembly, PLC Enclosure" Trotter Controls Inc. 7 Drawing 51900 "Installation, Manual control, Pilot Interface" Snow Engineering Co. 8 Drawing 60433 "Wire List, Wire Assembly, PLC Enclosure" Snow Engineering Co. 9 Drawing 60435 "Wire Assembly, PLC Enclosure" Snow Engineering Co. 10 Drawing 60437 "Assembly, Low Current Power Supply" Snow Engineering Co. 11 Drawing 60439 "Assembly, PLC Enclosure" Snow Engineering Co. 12 Drawing 60441 "Control System Wiring Schematic" Snow Engineering Co. 13 Drawing 60444 "Assembly, Pilot Interface" Snow Engineering Co. 14 Drawing 60501 " Assy, Toshiba computer" Snow Engineering Co. 15 Drawing 60514 "Assembly, Pilot Display" Snow Engineering Co. 16 Drawing 60516 "Shock resistant cradle for PLC" Snow Engineering Co. 17 Drawing 60668 "Calibration Procedure- Gatebox Angle" Snow Engineering Co 18 Drawing 60672 "Calibration Procedure, PLC Enclosure" Snow Engineering Co. 19 Drawing 60781 "Assy, Servo Card Mounting Module" Snow Engineering Co. Page 3 of 47
4 47 20 Drawing 80493 "Assy - Gatebox Actuator" Snow Engineering Co. 21 Drawing 80577 "Hydraulic System Installation" Snow Engineering Co. 22 Drawing 81387 "Hydraulic Manifold Assembly" Snow Engineering Co. 23 Drawing 81759 "Fitting Assy, Hydraulic Tank" Snow Engineering Co. KITS 24 Kit 1099-0001 "Encoder Upgrade Kit" Trotter Controls Inc. 25 Kit 1099-0002 "Power Supply Connector Upgrade" Trotter Controls Inc. 26 Kit 1099-0004 "Pilot Interface Back Cover Upgrade" Trotter Controls Inc. 27 Kit 1099-0005 "Ruggedized Ribbon Cable, Pilot Interface" Trotter Controls Inc. 28 Kit 1099-0014 "FRDS Manual PLC Mounting Hardware" Trotter Controls Inc. 29 Kit 1099-0015 "Analog Servo Card Standoffs" Trotter Controls Inc. 30 Kit 1099-0020 "Fan Hole Block Off Upgrade" Trotter Controls Inc. 31 Kit 1099-0031 "Kit Connector Screw, DSUB50 FRDS" Repair Trotter Controls Inc. 32 KIT 1099-0032 "60437 - PS Regulator Mount" Trotter Controls Inc. 33 Kit 1099-0033 "60437 - Low current PS Rebuild kit" Trotter Controls Inc. 34 Kit 1099-0034 "061E500 - High current PS Rebuild" kit Trotter Controls Inc. 35 Kit 1099-0037 " 209H5990 - PS Rebuild kit Trotter Controls Inc. 36 37 38 39 40 41 KIT 1097-0001 "Pilot interface (60444-1) standard rebuild / repair" KIT 1097-0002 "Low Current Power Supply (60437-1) - Standard rebuild/repair" KIT 1097-0003 "High Current Power Supply (061E500-1) - Standard rebuild/repair" KIT 1097-0004 "Redundant Power Supply (209H500-1) - Standard rebuild/repair" KIT 1097-0005 "Digital Servo Card (209G500-1) - Standard rebuild/repair" KIT 1097-0006 "Potentiometer Encoder Translator (5950-0001) - Standard rebuild/repair" Trotter Controls Inc. Trotter Controls Inc. Trotter Controls Inc. Trotter Controls Inc. Trotter Controls Inc. Trotter Controls Inc. 42 Kit 1099-0035 "FRDS Relay Replacement" Trotter Controls Inc. PARTS 43 Part 03-DL2032 ~ CR2032, 3V Lithium Battery Trotter Controls Inc. 44 Part 5200-0003 "Manual Panel Guard" Air Tractor Inc. 45 Part 60516-24 "Shock resistant cradle for PLC" Air Tractor Inc. 46 Part RTV-162 "(GE) Electronics Grade Silicone Adhesive" Page 4 of 47
5 47 SIL s 47 SIL-68-3 "FRDS Pilot Interface Overlay Replacement" Air Tractor Inc. 48 SIL-68-4 "Run Mode Switch / RF Rejection Upgrade" Air Tractor Inc. 49 SIL-74 "Power Supply and Encoder Update" Air Tractor Inc. 50 SIL-80 "Encoder Upgrade Installation" Air Tractor Inc. 51 SIL-81 "Pump Cooling Kit Installation" Air Tractor Inc. 52 SIL-82-10 "FRDS Pilot Interface Back Cover Kit" Air Tractor Inc. 53 SIL-82-12 "FRDS PLC Enclosure Maintenance" Air Tractor Inc. 54 SIL-82-13 "FRDS Relay Replacement" Air Tractor Inc. 55 SIL-82-14 "Power Supply Heat Sink" Air Tractor Inc. 56 SIL-82-15 "Analog Servo Card Maintenance" Air Tractor Inc. 57 SIL-82-16 "FRDS Dump switch resistor" Air Tractor Inc. 58 SIL-82-17 "FRDS Low Current Power Supply Rebuild" Air Tractor Inc. 59 SIL-82-18 "FRDS High Current Power Supply Rebuild" Air Tractor Inc. 60 SIL-82-3 "Hydraulic Pump Pressure Relief Adjustment" Air Tractor Inc. 61 SIL-82-4 "Current Limiter Installation" Air Tractor Inc. 62 SIL-82-5 "Auto Salvo Op. and Testing, w/ Manual System" Air Tractor Inc. 63 SIL-82-6 "Auto Salvo Op. and Testing, w/o Manual System" Air Tractor Inc. 64 SIL-82-7 "FRDS Connector Maintenance" Air Tractor Inc. 65 SIL-82-8 "FRDS Salvo Switch Guard" Air Tractor Inc. 66 SIL-82-9 "FRDS Accelerometer Assy Waterproofing" Air Tractor Inc. 67 SIL-83 "Shock Mount" Air Tractor Inc. 68 SIL-84 "Preventing Damage from Ice to the Fire Gate" Air Tractor Inc. 69 SIL-85 "Preventing Corrosion on the FRDS Shaft Support Plates" Air Tractor Inc. 70 SIL-86 "Pump Cooling Kit Installation" Air Tractor Inc. Page 5 of 47
6 47 Page 6 of 47 Table of Contents Overview... 3 References... 3 Table of Contents... 6 Objectives... 8 HYDRAULICS... 11 Hydraulic pump cooling kit installed... 11 Hydraulic pump additional cooling installed... 11 Hydraulic pressure relief... 11 Hydraulic valve coil retainer torque... 12 Hydraulic solenoid connectors... 12 Hydraulic reservoir level... 12 Hydraulic system leaks... 13 Hydraulic pump motor contactor (Pump Relay)... 13 Hydraulic oil change... 14 Hydraulic oil filter change... 14 Hydraulic breather / filter service... 14 Hydraulic accumulator pressure... 15 Servo null adjustment... 15 GATEBO... 16 Sacrificial anode installed... 16 Sacrificial anode condition... 16 Fire gate ice damage prevention... 16 Door seal condition... 17 Door mechanical condition... 17 Actuator over center adjustment... 17 Test hopper float operation... 18 Encoder upgrade (installed in place of gatebox potentiometer)... 18 Encoder upgrade connection... 19 PILOT INTERFACE... 19 Pilot Interface indicator lights... 19 Pilot Interface switches... 20 Pilot Interface connectors and other maintenance... 20 Pilot flight stick dump switch... 21 Dump switch resistor... 21 MANUAL CONTROL PANEL (MCP)... 22 Manual Interface (MCP) indicator lights (if present)... 22 Manual Interface switches (If present)... 22 Manual panel guard... 22 MISCELLANEOUS... 23 Test operation of the E-Dump systems... 23 Auto Salvo upgrade installed (with manual system)... 23 Auto Salvo upgrade installed (w/o manual system)... 23 Test Auto Salvo upgrade (with manual system)... 24 Test Auto Salvo upgrade (w/o manual system)... 24 Check accelerometer... 25 ENCLOSURE... 25 Replace system relays... 25 Relay retainer clips in place... 25 Replace PLC battery (PU11A, PU12A [E100] CPU)... 26
7 47 Replace PLC battery (T2 CPU)... 26 PLC Enclosure holes sealed... 29 PLC Enclosure lid seal condition... 29 PLC Enclosure door lock working properly... 30 Fan Block off kit... 30 Manual PLC mounts... 30 Run mode switch and upgrade... 31 Run mode switch test... 31 Check tightness of all screws in enclosure... 32 Connectors (enclosure gland plate)... 32 Power supply ~ Low current... 32 Power supply rebuild ~ Low current... 33 Power supply heat sink kit ~ Low current P/S, 60437-1... 33 Power supply ~ High current... 33 Power supply rebuild ~ High current... 34 Power supplies ~ Dual redundant... 34 Current limiter installed... 37 Analog servo card service and adjustment... 37 Digital servo card... 37 Vibration kit installed... 38 Vibration kit condition... 38 Checklist label... 40 CHECK OFF SHEETS... 41 Check off Sheet Daily... 41 Check off Sheet Weekly... 42 Check off Sheet Monthly... 43 Check off Sheet Yearly... 44 Check off Sheet 5 Year... 46 SUPPORT:... 47 APPENDI:... 47 Page 7 of 47
8 47 Objectives The purpose of this manual is to provide the factory recommended maintenance schedule and procedures for effective maintenance of the FRDS unit. The chart below includes the recommended service related procedures along with the recommended service interval for each item. Table 1 ~ Recommended service interval by maintenance task. Maintenance Recommended Service Interval per Maintenance Task Item Tasks Effectivity I n i t i a l l y Interval D W M Y a e o e i e n a l k t r y l h l y l y * y * * HYDRAULICS 1 Hydraulic pump cooling kit installed 2 Hydraulic pump additional cooling installed (Blower) 3 Hydraulic pressure relief 4 Hydraulic valve coil retainer torque 5 Hydraulic solenoid connectors 6 Hydraulic reservoir level 7 Hydraulic system leaks 8 Hydraulic pump motor contactor 9 Hydraulic oil change As Required 10 Hydraulic oil filter change As Required 11 Hydraulic breather service 12 Hydraulic accumulator pressure 13 Servo valve null adjustment GATEBO 14 Sacrificial anode installed 15 Sacrificial anode condition 16 Fire Gate ice damage prevention 17 Door seals in good condition 18 Door mechanical condition 19 Actuator over center adjustment 20 Test hopper float operation 21 Encoder upgrade installed in place of potentiometer 802-0001 thru 802-0067 22 Encoder upgrade connection 802-0001 thru 802-0067 5 Y e a r PILOT INTERFACE 23 Pilot Interface indicator lights function properly 24 Pilot Interface switches function properly 25 Pilot Interface connectors inspected, cleaned and sealed 26 Pilot flight stick switches function properly 27 Dump switch resistor installed 28 Manual Interface indicator lights function properly Page 8 of 47
9 47 Item Tasks Effectivity Page 9 of 47 Recommended Service Interval per Maintenance Task Maintenance Interval I D W M Y 5 n a e o e i i e n a Y t l k t r e i y l h l a a y l y r l * y l * y * 29 Manual Interface switches function properly 30 Manual Interface connectors inspected, cleaned and sealed 31 Manual Panel Guard 802-0066 and Subs 32 Pilot interface Rebuild 33 Check DSUB 50 Pilot Interface screw installation 34 ** Test operation of the pneumatic E-Dump system 35 Test operation of manual salvo MISCELLANEOUS 36 Auto Salvo Upgrade (with Manual system) Option installed 37 Test Auto Salvo Upgrade (with Manual Option system) 38 Auto Salvo Upgrade (w/o Manual system) Option installed 39 Test Auto Salvo Upgrade (w/o Manual Option system) 40 Check Accelerometer PLC ENCLOSURE 41 Replace system relays 42 Relay retaining clips in place 43 Replace PLC battery on PU11A,PU12A (E100) CPU VARIES 44 Replace PLC battery on T2 CPU VARIES 45 PLC Enclosure holes sealed 46 PLC Enclosure lid seal condition 47 PLC Enclosure door lock working properly 48 Fan hole block off kit installed (if applicable) 49 Manual PLC mounts installed 50 Check DSUB 50 retaining screws 51 Run mode switch installed (Factory install) Option 52 Run mode switch test 802-0066 and Subs 53 Check tightness of all screws in enclosure 54 Connectors-Enclosure 55 Power Supply Low Current (60437-1) 802-0001 thru 802-0176 56 Power Supply Low Current Rebuild 802-0001 thru 802- (60437-1) 0176 57 Power Supply Low Current Heat sink kit 802-0001 thru 802-0176 58 Power Supply High Current 802-0001 thru 802-0176 59 Power Supply High Current Rebuild 802-0001 thru 802-0176
10 47 Item Tasks Effectivity Recommended Service Interval per Maintenance Task Maintenance Interval I D W M Y 5 n a e o e i i e n a Y t l k t r e i y l h l a a y l y r l * y l * y * 60 Power Supplies Dual Redundant 802-0177 and Subs 61 Power Supply Dual Redundant Rebuild 802-0177 and Subs 62 Current limiter installed 63 Analog servo card serviced and adjusted 802-0001 thru 802-0176 64 Digital servo card 802-0177 and Subs 65 Digital servo card - rebuild 802-0177 and Subs 66 Vibration kit installed (Required for Fireboss) 67 Vibration kit condition 68 Install Checklist and Software Labels 69 Verify fans Inside PLC enclosure are operational * Daily, Weekly and Monthly maintenance intervals are; o System operational checks o Visual checks of hardware and associated indicators o Fluid level(s) checks Generally, the pilot performs these tasks but any informed personnel may perform the Daily, Weekly and Monthly tasks. Refer to the FRDS Operation Pocket Reference (located in the cockpit) for additional operational information. ** It is normal for personnel to leave some amount of liquid in the hopper overnight due to high winds, time to fill the hopper or to keep the chemicals used in retardant from setting up and becoming hard. In instances where the hopper can not be emptied at the end of the day perform the E-Dump check at the first opportunity but do not exceed one week before performing the E-Dump operational check. Page 10 of 47
11 47 HYDRAULICS Hydraulic pump cooling kit installed Overheating of the hydraulic pump has been observed on several aircraft in the field. A field kit was installed to provide blast-air cooling on the hydraulic pump when the aircraft is in flight to reduce overheating of the pump. Some details on the cooling kit are included below. A spacer provides a pathway for cooling air and isolates the hydraulic pump from heat generated by the electric motor. A cooling shroud directs external air around the hydraulic pump assembly and concentrates air on the hydraulic manifold. The kit helps reduce overheating while the aircraft is in flight. The kit is not effective unless the aircraft is in flight. Verify that the Cooling Kit has been installed per SIL-81. SIL-81 Pump Cooling Kit Installation SIL-86 Hydraulic Pump Additional Cooling (contains additional references) Hydraulic pump additional cooling installed Overheating of the hydraulic pump has been observed on aircraft while static on the ground when airflow from propeller wash or flight is not present to cool the pump. This kit provides an electric blower to provide airflow when the aircraft is on the ground. Install this kit in addition to the SIL-81 Pump Cooling Kit. Verify Kit installation per SIL-86. SIL-86 Hydraulic Pump Additional Cooling SIL-81 Pump Cooling Kit Installation (contains additional references) Hydraulic pressure relief Overheating of the hydraulic pump has been observed on several aircraft in the field. One of the primary reasons for overheating failures is an improperly adjusted mechanical pressure relief valve. The pressure relief setting must be set higher than the working pressure of the system to ensure that flow is not bypassed before the pump reaches its normal operating pressure of 3000 PSI. Test the pressure relief valve as specified in SIL-82-3 and adjust if necessary. Page 11 of 47
12 47 SIL-82-3 Hydraulic Pump Pressure Relief Adjustment (contains additional references) Hydraulic valve coil retainer torque Page 12 of 47 Improper operation of the hydraulic valves has been observed on some aircraft. This is sometimes attributed to the valve retainers being tightened excessively. Excessive torque on the valve coil retainer nuts can cause valve sticking or permanent damage to the valves. Follow instructions and processes outlined below. Remove valve coil retainers on the hydraulic valves located on the hydraulic manifold. Clean the metal stems if required. Apply 1 drop of blue Loctite (or equivalent) to threads. Retighten coil retainers to a very light torque of 2 ft-lb or less. Coils should just be held in place after tightening. References: Snow Engineering Co. Drawing 81387 Hydraulic Manifold Assembly Snow Engineering Co. Drawing 80577 Hydraulic System Installation Hydraulic solenoid connectors Broken or damaged connectors on the hydraulic solenoids may lead to system failures. Below is a basic description of tasks required to inspect and repair the connectors. Detailed information can be found in the referenced documents. Visually inspect the connectors. Replace any broken or damaged parts. Do not attempt to repair connector. Clean contacts and allow to air dry. Seal connector with dielectric grease. SIL-82-7 FRDS Connector Maintenance (contains additional references) Hydraulic reservoir level Verify that the hydraulic system is at a proper operational level. Let the aircraft and the hydraulic system cool to ambient temperature. Open the access port on the aircraft, this allows access to the hydraulic filler cap and filter. Twist the cap/filter counterclockwise and remove the dipstick from the reservoir.
13 47 Page 13 of 47 Check the dipstick to determine the oil level. Clean the dipstick and reinsert it to ensure an accurate reading. Add hydraulic oil if necessary. Do not over fill. Hydraulic oil recommended: Rando HDZ68 (Texaco) Do not run the system without adequate oil. Air can be introduced into the system causing cavitations and the following; o Pump damage o Poor performance o Low pressure o Overheating o Foaming and oil loss Hydraulic system leaks Hydraulic leaks can be a fire hazard and may cause extensive damage to the FRDS if not corrected. Keep the aircraft clean to aid in locating hydraulic leaks. Use an approved cleaning agent and rags. Clean the system, tanks, hoses, fittings and valves as required. Operate the system and inspect all hoses, fittings and components for leakage. Repair leaks as necessary. Hydraulic pump motor contactor (Pump Relay) The motor contactor is responsible for applying power to the hydraulic pump when the FRDS computer commands the pump to operate. This contactor has a finite life and should be replaced every five years to avoid unexpected pump failure (see SIL 802-82-13). The primary items to check are listed below. The high current wires connecting the battery & breaker to the motor must be tight to provide adequate voltage and current to the pump motor. Low voltage to the pump motor can cause the pump motor to stall or overheat. Excessive wire tension or torque on relay connection nuts can break the contactor housing. Inspect for a cracked or broken housing and replace the contactor if required. Strain relief wires as required to minimize stress on relay connections. Check the low current connections used to turn the relay on. Verify they are tight, the terminals are properly crimped and the wires are properly strain relieved. Use wire ties to provide proper strain relief if required. Repair as required. References:
14 47 SIL-82-13 FRDS Relay Replacement (contains additional references) Snow Engineering Co. Drawing 80577 Hydraulic System Installation Snow Engineering Co. Drawing 60441 FRDS Schematic Hydraulic oil change Over a period of time debris may build up in the filter element. Inspection or replacement of the breather is recommended at a regular interval. Page 14 of 47 Over a period of time, the hydraulic oil can experience viscosity breakdown and can become laden with debris and/or moisture. You should change the oil after a period of time based on usage or age. Typically the oil is good for a period of 600 aircraft operational hours or 2 years, whichever comes first. There are however mitigating circumstances; o Aircraft operating in extremely dry hot environments may see increased breakdown of the oil from heat. o Aircraft operating near coastal areas may see an increase in contamination by moisture. Inspect the oil regularly and change it if you suspect it has become contaminated. There is no easy way to tell if the oil requires changing other than to set a regular changing interval. Discolored, milky looking oil is a clear sign that the oil needs to be changed. The hydraulic oil filter should be changed at the same time as the oil. Hydraulic oil recommended: Rando HDZ68 (Texaco) Hydraulic oil filter change The Hydraulic filter is the primary line of defense against particulate contaminates. Replacing the filter regularly is an important part of the maintenance of the FRDS unit. Parts: High pressure filter element P/N: 5W357 (Grainger) Follow directions outlined in the FRDS Manual. Hydraulic breather / filter service The Hydraulic breather allows filtered air to get into and escape the hydraulic reservoir during system operation.
15 47 Parts: Air Breather with ¾ NPT, 81759-5 (Vescor:1306-2) Replace the breather element every 1 to 5 years. When replacing the breather, make sure to reuse or verify the dipstick level marks. Snow Engineering Co. Drawing 81759-1 Fitting Assy Hydraulic Tank Hydraulic accumulator pressure Page 15 of 47 The accumulator is used to store hydraulic energy for the FRDS to use when moving the doors quickly. For the accumulator to work properly, it must be charged with the appropriate nitrogen pressure. The pressure is checked and adjusted via a valve stem similar to that found on a car tire. To test the accumulator pressure, you must have a pressure gauge capable of reading 2000Lbs of pressure or you can use the method outlined in the FRDS Manual (Pilot Quick Check). Power off the aircraft and the FRDS. Pull the cover (blue bubble) in front of the Fire Gate Doors. Remove the valve stem cover on the accumulator. Use the pressure gauge to check the charge. It should be 1650PSI. o 1650 PSI Max o 1600 PSI Min To add pressure, a high pressure container of dry nitrogen fitted with a high pressure regulator is required. To decrease pressure, release nitrogen by pressing in on the valve stem. Servo null adjustment A misadjusted null can cause the doors to vibrate when they open. The null can also cause problems when trying to build pressure in Manual mode after making an initial drop. Adjustment of the servo valve null requires the following tools; o 3/8 open end wrench o 3/32 Hex / Allen key wrench Follow the procedure outlined in drawing 60668 - Sheet 1.
16 47 Snow Engineering Co. Drawing 60668 Sheet 1 Calibration Procedure- Gatebox Angle GATEBO Sacrificial anode installed The anode plates were added to help prevent corrosion on the FRDS shaft support plates. This anode allows the normal electrolytic actions to feed/corrode this consumable, replaceable part. Inspect to see if the sacrificial anode has been installed per SIL-85. If it s not present and is required, order SIL-85 from Air Tractor. Follow directions per the SIL. SIL-85 Preventing Corrosion on the FRDS Shaft Support Plates (contains additional references) Sacrificial anode condition The anode plates were added to help prevent corrosion on the FRDS shaft support plates. This anode corrodes as a normal consumable replacement part. Inspect the anode and replace if excessively corroded. Refer to SIL-85 for additional information including replacement parts. SIL-85 Preventing Corrosion on the FRDS Shaft Support Plates (contains additional references) Fire gate ice damage prevention Damage to the fire gate doors has been observed in aircraft due to freezing temperatures. Water gets into cracks in the fire gate center tube and freezes causing damage. Inspect to see if SIL-84 has been installed. If not, order SIL-84 from Air Tractor. Check for existing damage. Refer to SIL-84 for additional information including replacement parts. SIL-84 Preventing Damage from Ice to the Fire Gate Page 16 of 47
17 47 Door seal condition The gatebox door seals must be maintained to prevent leak free operation. A leaky seal can be cause for ground personnel to declare an AOG condition due to EPA concerns. Inspect the fire gate doors for damaged seals and proper linkage adjustment. Replace the seals if required. Door mechanical condition Proper mechanical condition of fire gate doors is important. Inspect for damaged, loose or missing hardware. Verify all locknuts on door hinges are tight and properly adjusted. Repair or replace as necessary. Actuator over center adjustment Verify doors arms are properly "toggled" over center when the doors are fully closed. It is critical that the arms are toggled over center. This action mechanically locks the doors closed preventing an inadvertent opening when hydraulic pressure is not present on the FRDS. Incorrectly timed gears or incorrectly adjusted linkage arms could prevent the arms from toggling over center resulting in an inadvertent dump. Gap.5 Inch (12mm) or less (GOOD) Gap >.5 Inch (12mm) (BAD) Figure 1 - Fully broke over closed Figure 2 - Not broke over properly Figure 3 - Fully broke over open Page 17 of 47
18 47 Follow information included in the references. o Figure 1 shows a properly adjusted actuator in the closed position. o Figure 2 shows the linkage not fully broke over although the shaft appears to be. o Figure 3 shows the point where the linkage is fully broke over in the open direction. Snow Engineering Co. Drawing #80493-1 Assy - Gatebox Actuator Snow Engineering Co. Drawing #80577 Hydraulic System Installation Snow Engineering Co. Drawing 60668 Page 1 Calibration Procedure- Gatebox Angle Test hopper float operation Operation of the hopper float is critical for accurate FRDS operation. This provides the pilot and FRDS with the current level of retardant in the hoppers. Directions for adjusting, repairing and replacing the hopper float or the hopper pot, can be found in the FRDS - System Maintenance & Troubleshooting Guide. Parts: 60428-1 Assy Level Potentiometer Encoder upgrade (installed in place of gatebox potentiometer) Verify that SIL-80, Encoder Upgrade Installation, has been performed. This upgrade improves reliability of the gatebox position sensor and makes adjustment of the home position more reliable. Potentiometer failure ~ Gatebox potentiometer fails due to moisture or vibration of wiper damaging conductive plastic resistance element. Potentiometer calibration problem ~ Calibration of the door angle during replacement of the door angle potentiometer has caused problems in the field due to the involved field calibration procedure. Inspect to see if SIL-80 has been installed. If not, order SIL-80 from Air Tractor. Refer to SIL-80 for installation information and replacement parts. Parts: Kit 1099-0001 Encoder Upgrade Kit SIL-74 Power Supply and Encoder Update (contains additional references) SIL-80 Encoder Upgrade Installation (contains additional references) Page 18 of 47
19 47 Encoder upgrade connection Inspect the quality of the connection to the encoder upgrade. Remove all power to the aircraft and the FRDS unit. Remove the fairing located in front of the fire gate doors (blue bubble). Remove the connectors from the encoder upgrade canister. Clean and inspect the connectors and the connections on the canister. Pack the female pins of the connectors with silicone dielectric grease. Apply a small amount of the dielectric grease to the threads of the connector. Reconnect and tighten the electrical connection. Replace the spherical gatebox cover. SIL-80 Encoder Upgrade Installation (contains additional references) SIL-82-7 FRDS Connector Maintenance (contains additional references) PILOT INTERFACE Pilot Interface indicator lights Check the Pilot Interface regularly for broken, switch s, lights and wires. Test the switches, lights, indicators and selectors for proper operation. Replace any damaged or missing indicators prior to testing any others. Power must be on to the FRDS unit during testing and off during repairs. Hydraulic pressure is not necessary for the following tests. You can test most of the indicators by pressing the Press to Test light firmly. The power switch should be in the auto position when checking lamps on the auto panel. The power switch should be set to the middle position when testing the lamps on the manual panel. The LED s, used to display numbers and hydraulic pressure, are replaceable but we recommend having the factory perform the repair. Parts: KIT 1097-0001 Pilot interface (60444-1) standard rebuild / repair Snow Engineering Co. Drawing 60444 Rev "D" Assembly, Pilot Interface Snow Engineering Co. Drawing 60514 Assembly, Pilot Display Page 19 of 47
20 47 Pilot Interface switches Check the Pilot Interface regularly for broken, switch s, lights and wires. Test the switches, lights, indicators and selectors for proper operation. Replace any damaged or missing switches prior to testing any others. The Coverage Level, Gallons to Dump and Ground Speed switches are not field repairable or replaceable. Exchange or factory repair of the pilot interface is the only option. The POWER and ARM switches can be replaced if malfunctioning or damaged. The BRIGHTNESS potentiometer and knob are also replaceable. Parts: KIT 1097-0001 Pilot Interface (60444-1) standard rebuild / repair (factory only) Snow Engineering Co. Drawing 60444 Rev "D" Assembly, Pilot Interface Snow Engineering Co. Drawing 60514 Assembly, Pilot Display Pilot Interface connectors and other maintenance Inspect, clean and seal the connectors of the Pilot Interface. Operation of the switches, lights, indicators and selectors should be tested for proper operation. There are also some upgrades / parts for older Pilot Interfaces. See reference materials below. Reference the corresponding tables in the FRDS - System Maintenance & Troubleshooting Guide to determine correct operation of the switches and lights. SIL-82-7 details the requirements for Pilot Interface connector maintenance. See SIL-82-10 for information on Pilot Interface cover upgrades. See Sil-68-3 for information on replacing the polycarbonate cover on the Pilot Interface. Parts: Kit 1099-0005 Ruggedized Ribbon Cable, Pilot Interface Kit 1099-0004 Pilot Interface Back Cover Upgrade SIL-82-7 FRDS Connector Maintenance (contains additional references) SIL-82-10 FRDS Pilot Interface Back Cover Kit (contains additional references) SIL-68-3 FRDS Pilot Interface Overlay Replacement (contains additional references) Snow Engineering Co. Drawing 60441 Control System Wiring Schematic Snow Engineering Co. Drawing 60444 Rev. "D" Assembly, Pilot Interface Snow Engineering Co. Drawing 60514 Assembly, Pilot Display Page 20 of 47
21 47 Pilot flight stick dump switch Test the dump switch on the Pilot flight stick for proper operation. Initial testing of the dump switch doesn t require power to the aircraft. A basic feel test can be done to verify that the switch moves from the depressed to pressed position and back with out sticking. Any binding or abnormal physical resistance should be addressed. The only easy way to test the electrical part of the switch is to use a DMM (Digital Multimeter) or other device to measure resistance. Unplug the 14 pin, high-level harness connector from the PLC enclosure. Check the resistance between pin A (wire -37) and B (wire -38) on the 14 pin circular connector (60448-2). In the open position (not depressed), the resistance should be high across the switch (greater than 50,000 ohms). When the button is depressed, the reading should be close to a short circuit, low impedance, reading. The reading should be stable and less than 2.0 Ohms. Any bouncing in the reading may indicate a bad or poor connection in the switch. Replace the switch if necessary and repeat test. Perform connector maintenance if required. Snow Engineering Co. Drawing 60441 Control System Wiring Schematic SIL-82-7 FRDS Connector maintenance (contains additional references) Dump switch resistor Excessive moisture or corrosion in the connectors or dump switch has caused inadvertent door openings when the system is armed. A resistor has been added to increase the required current to trigger a delivery. This keeps small electrical leakage currents from causing a false delivery. It is still important that connector maintenance be performed. Install Dump switch resistor 061P532-276 per instructions included in SIL-82-16. Parts: Part 061P532-276 Dump switch resistor Drawing 061P531 "Wire Assembly, PLC Enclosure" Drawing 60435 "Wire Assembly, PLC Enclosure" SIL-82-7 FRDS Connector Maintenance (contains additional references) SIL-82-16 FRDS Dump switch resistor (contains additional references) Snow Engineering Co. Drawing 60441 Control System Wiring Schematic Page 21 of 47
22 47 MANUAL CONTROL PANEL (MCP) Manual Interface (MCP) indicator lights (if present) The Manual Interface is to be checked regularly for broken or missing switch s, lights and wires. Operation of the switches, lights, indicators and selectors should be tested for proper operation. Replace any damaged or missing indicators prior to testing MCP. Power should be set to the MANUAL middle position on the Pilot Interface. Hydraulic pressure is not necessary for the following tests. The indicators can be tested by pressing the indicator in firmly (Push to Test). The indicator for the yellow Salvo button is integral to the switch and should only be tested when testing the switch. The doors will open, regardless of the Pilot Interface settings including the OFF position, if power is present on the aircraft and the Salvo button is pressed. Snow Engineering Co. Drawing 60444 Rev. "D" Assembly, Pilot Interface Snow Engineering Co. Drawing 60514 Assembly, Pilot Display Manual Interface switches (If present) The Manual interface is to be checked regularly for broken, switch s, lights and wires. Operation of the switches, lights, indicators and selectors should be tested for proper operation. Replace any damaged or missing switches prior to testing. Reference MCP switches operation table in the FRDS - System Maintenance & Troubleshooting Guide to verify correct switch operation. Snow Engineering Co. Drawing 60444 Rev. "D" Assembly, Pilot Interface Snow Engineering Co. Drawing 60514 Assembly, Pilot Display Manual panel guard Personnel entering or exiting the cockpit can damage the FRDS Salvo switch included on aircraft equipped with a Manual Interface Panel. A protective guard is available to protect the backside of the Manual Interface Panel from accidental damage. The Salvo switch guard should be installed on all AT-802s to protect the manual control panel switches from accidental damage. Page 22 of 47
23 47 Check to make sure manual panel guard is installed. Follow instructions in SIL-82-8 to install a guard if required. Parts: Part 5200-0003 ~ Manual Panel Guard SIL-82-8 FRDS Salvo Switch Guard (contains additional references) Snow Engineering Co. Drawing 51900 Installation Manual control Pilot Interface MISCELLANEOUS Test operation of the E-Dump systems Page 23 of 47 Testing of the E-dump systems at a regular interval helps to ensure the system will work in the event it is needed. There are different types of E-Dump systems on aircraft. It will require referencing the operator s manual for details of each system. Refer to the FRDS - System Maintenance & Troubleshooting Guide on the use and diagnostics of the manual salvo system. Refer to the flight manual for information on operation of the pneumatic E- Dump system. Verify that power is removed from the FRDS unit and that the doors are opened by the pneumatic system. Auto Salvo upgrade installed (with manual system) An upgrade has been incorporated in many aircraft to allow a secondary system to open the doors in the event of a problem with the automatic PLC or servo control system. There are two types of Auto Salvo systems; o Systems with Manual Interface o Systems without a Manual Interface Follow instructions in SIL-82-5. SIL-82-5 Auto Salvo Operation and testing with manual system (contains additional references) Auto Salvo upgrade installed (w/o manual system) An upgrade has been incorporated in many aircraft to allow a secondary system to open the doors in the event of a problem with the automatic PLC or servo control system.
24 47 There are two types of Auto Salvo systems; o Systems with Manual Interface o Systems without a Manual Interface Follow instructions in SIL-82-6. SIL-82-6 Auto Salvo Operation and testing without manual system Test Auto Salvo upgrade (with manual system) An upgrade has been incorporated into many aircraft to allow a secondary system to open the doors in the event of a problem with the automatic PLC or servo control system. There are two types of Auto Salvo systems; o Systems with Manual Interface o Systems without a Manual Interface Follow instructions and processes outlined in SIL-82-5. SIL-82-5 Auto Salvo Op. and Testing, w/ Manual System (contains additional references) Trotter Controls Inc. Drawing 061P500 Assembly, PLC Enclosure Trotter Controls Inc. Drawing 061P532 Wire List, Wire Assembly, PLC Enclosure Trotter Controls Inc. Drawing 061P531 Wire Assembly, PLC Enclosure Test Auto Salvo upgrade (w/o manual system) An upgrade has been incorporated into many aircraft to allow a secondary system to open the doors in the event of a problem with the automatic PLC or servo control system. There are two types of Auto Salvo systems; o Systems with Manual Interface o Systems without a Manual Interface (applies to this document) Follow instructions and processes outlined in the document. Additional references are as follows SIL-82-6 Auto Salvo Op. and Testing, w/o Manual System (contains additional references) Snow Engineering Co. 60433 Wire List, Wire Assembly, PLC Enclosure Snow Engineering Co. 60435 Wire Assembly, PLC Enclosure Snow Engineering Co. 60439 Assembly, PLC Enclosure Page 24 of 47
25 47 Check accelerometer Excessive moisture in the accelerometer assembly can cause a loss of +12 volts in the system and subsequent problems with system operation. Refer to SIL-82-9 FRDS Accelerometer Assy Waterproofing for instructions. Refer to the FRDS - System Maintenance & Troubleshooting Guide s diagnostics section for testing the Accelerometer. SIL-82-9 FRDS Accelerometer Assy Waterproofing (contains additional references) ENCLOSURE Replace system relays Aircraft five years and older have had problems caused by intermittent relay operation. Lost retaining relay clips can allow relays to come unplugged from their bases, causing improper or failed operation of the FRDS doors. Follow directions laid out in SIL-82-13. Parts: KIT 1099-0035 FRDS Relay Replacement SIL-82-13 FRDS Relay Replacement (contains additional references) Trotter Controls Inc. Inc. Drawing 061P500 Assembly, PLC Enclosure Relay retainer clips in place It has also been observed that lost relay retaining clips may allow relays to come unplugged from their bases causing improper or failed operation of the FRDS doors. During the preventative maintenance cycle verify that all relays are properly secured using the clips designed for use on the relays. If any clips are missing replace them with correct mounting clips. Part: KIT 1099-0035 FRDS Relay Replacement Page 25 of 47
26 47 SIL-82-13 FRDS Relay Replacement (contains additional references) Trotter Controls Inc. Drawing 061P500 Assembly, PLC Enclosure Replace PLC battery (PU11A, PU12A [E100] CPU) Replacement of the PLC battery is important. The battery allows the CPU to retain the g-leak values developed during calibration. Battery replacement takes approximately 15 minutes. Detailed instructions are in the FRDS - System Maintenance & Troubleshooting Guide. Turn Master power off to the aircraft and disconnect any APU devices. Gain access to the PLC enclosure. Remove the CPU Card. Remove the old battery Install the new battery. Complete replacement within about ten minutes to prevent data loss! Reinstall the CPU card and reconnect connector. Parts: Part options ~ DL2032 (Duracell), CR2032 (Panasonic) or equivalent 3V Lithium Battery Replace PLC battery (T2 CPU) Replacement of the PLC battery is important. It is used to store the calibrated leakage values. Remove the PU234E T2 CPU from the PLC Rack (Figure 4). Turn the PU234E T2 CPU with the back facing up and remove the plastic clip. Pull the sideboard with battery away from the main circuit board (Figure 5). Page 26 of 47
27 47 Figure 4 - T2 CPU SEPARATE CLIP MAIN BOARD BATTERY Figure 5 - Clip removed Page 27 of 47
28 47 CONNECTOR BATTERY Figure 6 - Battery Holder Disconnect the battery connector, shown in Figure 6. Remove the battery by lifting up the rear of the battery and sliding it out as shown in Figure 7. Figure 7 - Removing Battery Page 28 of 47
29 47 Figure 8 - Toshiba ER6V/ 3.6V Lithium The battery is a common 3.6 volt lithium battery, with solder tabs, commonly available from most electronics parts vendors. See the reference below for replacement battery information. Replace the battery by cutting the heat shrink from the battery and unsolder the wires connecting to the battery. Solder in the new battery, maintaining proper polarity. Reassembly is reverse of disassembly Optionally you can also purchase the complete battery assembly if so desired. Contact Air Tractor or your dealer for a replacement battery assembly. Parts: Part Tadiran, # TL-5104/TBP, Lithium, AA, Solder Tab, 2100mAh, 3.6V Lithium Battery PLC Enclosure holes sealed Some cabinet s have unused holes along the sealing edge of the PLC enclosure door. In some cases the plastic hole plugs come out and are lost. These holes are to be filled using RTV-162 Electronics Grade Silicone or equivalent. Refer to SIL-82-12 for installation instructions. SIL-82-12 FRDS PLC Enclosure Maintenance (contains additional references) PLC Enclosure lid seal condition Check the condition of the lid seal. Replace the enclosure door seal if damaged. Refer to SIL-82-12 for installation instructions. SIL-82-12 FRDS PLC Enclosure Maintenance (contains additional references) Page 29 of 47
30 47 PLC Enclosure door lock working properly Check the condition of the enclosure door lock. Repair or replace the lock if damaged. Refer to SIL-82-12 for installation instructions. SIL-82-12 FRDS PLC Enclosure Maintenance (contains additional references) Fan Block off kit The purpose of the fan block-off kit is to seal up enclosures on aircraft originally designed with fan-forced ventilation. Installation of the fan block off kit significantly reduces ingress of moisture, dust or other contaminates into the PLC enclosure. Inspect the PLC enclosure for the FRDS unit and verify if the unit requires the Fan Hole Block-Off Upgrade. Order Kit 1099-0020 Fan Hole Block-Off Upgrade. Refer to SIL-82-12 for installation instructions. Parts: Part RTV-162 Electronics grade silicone adhesive Kit 1099-0020 Fan Hole Block Off Upgrade SIL-82-12 FRDS PLC Enclosure Maintenance (contains additional references) Trotter Controls Inc. Drawing 061P500 Assembly, PLC Enclosure Manual PLC mounts The Manual PLC should be securely installed on the PLC enclosure door by two screws, spacers and threaded spacers. This kit prevents the Manual PLC from coming off the DIN rail causing damage to the Manual PLC or other components as it bounces around inside the enclosure. Install as shown in drawing 061P500 or 60439 depending on aircraft configuration. Parts: Kit 1099-0014 FRDS Manual PLC Mounting Hardware Trotter Controls, Inc. Drawing 061P500 Assembly, PLC Enclosure Page 30 of 47
31 47 Run mode switch and upgrade The Run Mode switch allows you to select the mode of the FRDS computer. The Run Mode Switch is not a field installable kit. It requires upgrading the Manual PLC software as well as special interconnects for older aircraft. The Run Mode Switch upgrade is a factory only upgrade. Refer to SIL-68-4. SIL-68-4 Run Mode Switch / RF Rejection Upgrade (contains additional references) Run mode switch test Systems shipped on aircraft subsequent to 802-0104 are equipped with a Run Mode Switch located on the left hand side of the PLC enclosure (061P500-1). This switch allows you to select the mode of the FRDS computer. The Run Mode Switch is not a field installable kit. It requires upgrading the Manual PLC software as well as special interconnects for older planes. Figure 9 To test the selector switch, check its operation according to Table 2. Turn the Power and Arm switches on the Pilot Interface to the OFF position to ensure the doors do not open inadvertently. Set the switch to the various positions shown in the table below and verify that the LED s on the rightmost DI31 card (061P501-5) light up per the table below. Table 2 ~ Run Mode Switch Expected States Switch Position Led #2 Led #3 Led #4 Led #5 Normal Off Off Off Off Learn On Off Off Off Diagnostic Off On Off Off Spare Off Off On Off Reset Learning Off Off Off On Page 31 of 47
32 47 SIL-68-4 Run Mode Switch / RF Rejection Upgrade Trotter Controls Inc. Drawing 061P531 Wiring Schematic, PLC Enclosure Check tightness of all screws in enclosure Due to vibrations caused by the aircraft, hardware can become loose. Check all screws, nuts and bolts. Do not over tighten screws! Check all Philips head screws on PLC chassis and I/O cards. Check all screws on terminal blocks TB1 and TB2. Check enclosure back panel, servo card and mounting hardware. Trotter Controls, Drawing 061P500 Assembly, PLC Enclosure Connectors (enclosure gland plate) Moisture and chemicals used for spraying and fire suppression can cause corrosion and damage inside the connectors of the FRDS unit. SIL-82-7 details the importance of proper preventive maintenance of the connectors used on FRDS units and describes the required maintenance procedures. Refer to and follow the instructions in SIL-82-7. Parts: Kit 1099-0031 Connector Screw, DSUB50 FRDS Repair SIL-82-7 FRDS Connector Maintenance (contains additional references) Power supply ~ Low current The purpose is to ruggedize the components of the power supply to prevent possible damage from vibration. Refer to and follow the instructions in SIL-82-14. Drawing 061P500-3 Rev A Assembly, PLC Enclosure Drawing 60437 Assembly, Low Current Power Supply Page 32 of 47
33 47 Power supply rebuild ~ Low current Rebuild the Low-current power supply, 60437, every five years to ensure continued operation and avoid failures. The electrolytic capacitors can and will deteriorate with time. They can have the following failures: o Excess leakage current o Overall failure To rebuild the power supply follow the directions specified in SIL-82-17. To send the power supply in for factory rebuild; o Remove power supply from aircraft o Order P/N: 1097-0002 Repair service o Send power supply to Air Tractor Parts Department for repair / rebuild Parts: Kit 1099-0033 60437 - Low current PS Rebuild kit Service: 1097-0002 Repair service SIL-82-17 FRDS Low Current Power Supply Rebuild (contains additional references) Power supply heat sink kit ~ Low current P/S, 60437-1 The purpose is to upgrade the 60437 Low-Current power supply used on older FRDS units. On older aircraft, the voltage regulator may overheat in certain conditions. It is also prone to damage by service personnel. A kit has been developed to add mechanical stability as well as additional cooling. Refer to and follow the instructions in SIL-82-14. Parts: PART 1099-0032 60437 - PS Regulator Mount Service: 1097-0002 Repair service SIL-82-14 Power Supply Heat Sink (contains additional references) Trotter Controls Inc. Drawing 061P500-3 Rev A Assembly, PLC Enclosure Drawing 60437 Assembly, Low Current Power Supply Power supply ~ High current The purpose is to ruggedize the components of the power supply to prevent possible damage from vibration. Page 33 of 47
34 47 Refer to and follow the instructions in SIL-82-18 pertaining to ruggedizing the unit. Service: 1097-0003 High Current Power Supply (061E500-1) - Standard rebuild/repair Trotter Controls Inc. Drawing 061E500 High current power supply SIL-82-18 FRDS High Current Power Supply Rebuild (contains additional references) Power supply rebuild ~ High current Page 34 of 47 Every five years, the high current power supply, 061E500, should be rebuilt. The electrolytic capacitors of the power supply can have the following failures: o Excessive leakage current o Overall failure Follow the directions specified in SIL-82-18. Parts: Kit 1099-0034 061E500 - High current PS Rebuild kit Service: 1097-0003 High Current Power Supply (061E500-1) - Standard rebuild/repair SIL-82-18 FRDS High Current Power Supply Rebuild (contains additional references) Trotter Controls Inc. Drawing 061E500 High current power supply Power supplies ~ Dual redundant The dual redundant power supplies generally do not require preventative maintenance work. Check to make sure all standoffs are tight. There are nine (9) standoffs holding the top and bottom boards together. These standoffs are used to conduct power between the boards so it is essential that they are tight. Verify that the switches shown in Figure 10 are both ether in the INT or ET position. Verify that all connectors are seated and that those with securing screws are tight. Do not over tighten! Make sure the board is ruggedized to prevent damage to components from vibration. Use RTV-162 electronics grade silicone adhesive to affix parts as shown in Figure 11 and Figure 12 Every 5 years the electrolytic capacitors should be replaced. o Order Kit # 1099-0037 for replacement capacitors o Order kit # 1097-0004 for factory rebuild and testing of the power supply Parts: Kit 1099-0037 Kit, 209H5990 - PS Rebuild kit
35 47 Service: 1097-0004 Redundant Power Supply (209H500-1) - Standard rebuild/repair Trotter Controls Inc., Drawing 209H5990 Redundant Power Supply STANDOFFS CONNECTORS SWITCHES Figure 10 - Dual Redundant Power Supply Page 35 of 47
36 47 Figure 11 - Top View Figure 12 - Bottom View Page 36 of 47
37 47 Current limiter installed A current limiter has been developed to eliminate the possibility of blown fuses on the Toshiba PLC power supply due to voltage transients on the aircraft. SIL- 82-4 details the purpose of the inrush current limiter and outlines the installation and testing procedures. Refer to and follow the instructions in SIL-82-4. SIL-82-4 Current Limiter Installation (contains additional references) Trotter Controls, Inc. Drawing 061P501-1 Rev: A ASSY TOSHIBA COMPUTER Trotter Controls, Inc. Drawing 061P531-1 Rev: J, Sheet 1 WIRING SCHEMATIC PLC ENCLOSURE Snow Engineering Co. Drawing 60501-1 Rev: B ASSY TOSHIBA COMPUTER Snow Engineering Co. Drawing 60435 Rev: F, Sheet 2 WIRING SCHEMATIC PLC Analog servo card service and adjustment The purpose of SIL-82-15 is to outline procedures required to repair, maintain and upgrade the Analog Servo Card used in older FRDS units. Refer to and follow the instructions in SIL-82-15. Parts: Kit 1099-0015 Analog Servo Card Standoffs Part RTV-162 (GE), Electronics Grade Silicone Adhesive SIL-82-15 Analog Servo Card Maintenance (contains additional references) Snow Engineering Co. Drawing 60439 Assembly, PLC Enclosure Snow Engineering Co. Drawing 60668 Calibration Procedure, Gatebox Angle Snow Engineering Co. Drawing 60672 Calibration Procedure, PLC Enclosure Snow Engineering Co. Drawing 60781-1 ASSY, Servo Card Mounting Module Digital servo card The purpose of this report is to detail general information regarding testing and setup of the digital servo card (209G500-1). Anytime the encoder rotational position is disturbed, the home position for the doors must be set as described in the manual. When the system is, healthy, LED3 will flash steady at a rate of about 1 flash per second with no long pauses between flashes. If an error is detected the LED will flash an error code. The number of LED flashes displayed when a specific fault is detected is shown in Table 3 below. Page 37 of 47
38 47 Table 3 Errors displayed by servo card FAULT_ENCODER_RANGE 2 Goes into analog "limp mode FAULT_ENCODER_BUSY 4 Goes into analog "limp" mode FAULT_ENCODER_MISSING 6 Goes into analog "limp" mode FAULT_ENCODER_NOTLOW 8 Goes into analog "limp" mode FAULT_EEPROM_INVALID 10 Goes into analog "limp" mode FAULT_VOLTAGE_RANGE Sets output current to open the 12 doors Default: No error detected this is a no fault display 16 during recovery Service: 1097-0005 Digital Servo Card (209G500-1) - Standard rebuild/repair Trotter Controls Inc. Drawing 061P500 Assembly, PLC Enclosure Vibration kit installed A new mounting bracket and newly designed shock suppressors have been developed to significantly reduce the vibration and shock loads seen by the FRDS computer. The intense vibrations and shocks that Fire Boss aircraft experience cause extreme stress to the FRDS control enclosure and its contents. The vibration kit is required for Fire Bosses. It is not required for wheeled aircraft but it is strongly recommended. Refer to and follow the instructions in SIL-83 and included in Kit 60616-24. Parts: PART 60516-24 Shock resistant cradle for PLC SIL-83 Shock Mount (contains additional references) Vibration kit condition Check the condition of the components of the shock cradle and bumpers yearly at a minimum. Make sure the hardware is tight. Insure condition of the springs is acceptable. Verify that bumpers are in acceptable condition. Inspect cradle-mounting tabs for cracks. Inspect all components for excessive corrosion and signs of wear. Page 38 of 47
39 47 SPRINGS BUMPERS Figure 13 - Vibration Kit Components INSPECT Figure 14 - Cradle mounting tab Snow Engineering Co. Drawing 60516-24 Shock resistant cradle for PLC SIL-83 Shock Mount (contains additional references) Page 39 of 47