PURPOSE: To explain the removal and replacement of the SK Model Motor Drives. PARTS REQUIRED: 20216-3, Seakeeper Motor Drive Box with PFC Circuit Protection 40025, Bulk Hose, 3/8 40026, Hose Clamp, Size 06 (11mm-20mm) Small bucket Absorbent rags or towels Plugs (2) for hose ends Caps (2) for coolant ports on Sevcon Motor Drive Box Teflon Based Thread Sealant 50/50 glycol coolant TOOLS REQUIRED: Ratchet Handle, 1/4" Drive (e.g. Craftsman Model # 44807) Socket, 10mm, 1/4 Drive (e.g. Craftsman Model # 34606) Socket, 1/4 Inch, 1/4 Drive (e.g. Craftsman Model # 34592) Extension, 3 Inch, 1/4 Drive (e.g. Craftsman Model # 43345) Ratcheting Combination Wrench, 10mm (e.g. Craftsman Model # D815680) Screwdriver, Phillips, No. 2 (e.g. Craftsman Model # 41295) Screwdriver, Straight Slot, 1/4 Inch (e.g. Craftsman Model # 41584) Utility Knife (e.g. Craftsman Model # 94848) REMOVAL PROCEDURE: Ensure All AC Power to Gyro is OFF, and the Breaker is Tagged Out to Prevent Accidental Power-Up. 1. Identify and record the existing Sevcon Motor Drive Box information. P a g e 1
a. Gyro model number b. Gyro serial number c. Vessel information d. Sevcon Motor Drive Box Part number e. Sevcon Motor Drive Box Serial number 2. Verify AC power to Sevcon Motor Drive Box is OFF. a. Verify AC circuit breaker to the Seakeeper Gyro is secure in the OFF position to prevent accidental power up while working. 3. Verify the Gyro flywheel is not spinning a. Verify Motor Speed indication on Display is zero (0) RPM 4. Remove the cover from Sevcon Motor Drive Box a. Use a No. 2 Phillips Screwdriver b. Keep the screws for re-use later P a g e 2
c. AC supply source must be turned off and flywheel must not be spinning and at zero (0) RPM or shock may result. 400V DC Motor Power AC Input Terminals d. Verify the AC input power is OFF by measuring the AC voltage on the AC power input terminals. e. Make a DC voltage measurement on the 400V DC Motor power terminals to verify no Voltage is present. 5. Molex Connector Locking Tab Molex Connector CPA CPA Seated CPA Unseated a. Pull CPA (Connector Position Assurance) down being careful not to damage it b. Press on the Locking Tab and pull the connector away from the SEVCON Motor Drive Box c. Inspect CPA, Locking Tab and connector for damage d. If the Molex connector is damaged, contact Seakeeper a. Reference Seakeeper Work Instruction WI-093 For Molex Connector repair/replacement procedures P a g e 3
6. Disconnect cables/leads by flipping up orange tabs and removing grounding screws Disconnect Cables from Terminal Blocks and Screws a. AC INPUT b. SW PUMP c. MOTOR d. Shield termination method is important e. Newer Sevcon Motor Drive Box may not have the brass brush grommet for the braided shield P a g e 4
Brass Brush Grommet f. If motor drive cable has a braided shield, the brass brush grommet may need to be removed from old SEVCON Motor Drive Box and re-used in replacement SEVCON Motor Drive Box Braided Shield g. If the motor cable is a foil shield, then remove the brass brush grommet and do not use with the replacement Motor Drive box. 7. Remove Cables from Sevcon Motor Drive Box P a g e 5
Cable Gland Nuts a. Remove nuts from cable glands and pull cables out of Sevcon Motor Drive Box b. Ensure gland nuts and rubber grommets remain on cables 8. Replace cover on Sevcon Motor Drive Box a. Use a No. 2 Phillips Screwdriver b. Replace screws from Removal step 4.b 9. Disconnect the two coolant hoses and grounding wire a. Assure no coolant spills onto electrical components, as damage will result P a g e 6
Coolant Hoses Ground Wire b. Place a small bucket under the coolant ports to collect glycol coolant that may spill out c. Use absorbent rags or towels to assist capturing any coolant that may spill d. Loosen the hose clamps with 1/4 inch socket or straight-slot screwdriver so the hoses can be pulled off e. Try to remove hose ends without damaging them, or the hoses will have to be replaced f. Drain some of the coolant in the hoses into the bucket g. Temporarily seal off the glycol hose ends with plugs (or 3/8 inch bolts) h. Temporarily tighten the hose clamps back down on the plugs i. Clean up any coolant spilled on the gyro, the panels, the frame, and the Sevcon Motor Drive Box j. Using 10mm wrench or socket remove grounding wire and note washer placement 10. Remove four (4) M6 bolts that mount the Sevcon Motor Drive Box from underside of Box Mounting Bolts P a g e 7
Mounting Bolts Use a 10mm socket and ratchet or a ratcheting 10mm wrench a. Keep the M6 bolts & lock washers for re-use later 11. Remove the old Sevcon Motor Drive Box a. With the removed Sevcon Motor Drive Box completely free from the gyro, move it around with the coolant ports above the bucket to drain all the glycol from inside Remove Fittings and Retain For Re-Use P a g e 8
b. Remove brass coolant line fittings and retain for future use IF NEEDED i. Take care not to damage the fittings if re-use is required ii. The replacement Motor Drive Box package contains new fittings. c. When the old Sevcon Motor Drive Box is completely free of glycol, install caps on the coolant ports (or similar plug material that can be readily removed) d. Place the removed Sevcon Motor Drive Box in the same shipping container from which the replacement box was delivered, or i. A suitable shipping container and secure the packing material firmly to protect the unit. e. Seal the container with packing tape for shipment back to Seakeeper P a g e 9
REPLACEMENT PROCEDURE: 1. Identify and record a. New Motor Drive Box Part number (e.g. 20216-3) b. New Motor Drive Box Serial number (e.g. 1507101525) 2. Install brass coolant fittings into new Sevcon Motor Drive Box P a g e 10
Re-Install Brass Fittings a. Clean threads on brass fittings b. Apply Teflon tape or Teflon based thread sealant compound to brass fitting threads c. Install fittings in original location and orientation into new Sevcon Motor Drive Box 3. Install a new Sevcon Motor Drive Box. a. Use the M6 bolts & lock washers you saved from Removal step 10.a b. Replace four (4) M6 bolts that mount the new Sevcon Motor Drive Box with 10mm socket and ratchet or a 10mm ratcheting wrench 4. Verify the cover is still secure on the new Sevcon Motor Drive Box. a. If not put it on. This will prevent any accidental spillage of coolant or other liquid onto the internal drive box components 5. Reconnect the two coolant hoses onto the hose barbs of the new Sevcon Motor Drive Box. a. Loosen the hose clamps and remove the plugs from the ends of the existing glycol hoses b. There should not be very much coolant in the ends of the hoses to leak or spill, however, avoid leaks or spills of glycol onto anything c. Replace the hoses onto the new Sevcon Motor Drive Box d. Replace the hose clamps into position on the hose barbs and tighten with 1/4 inch socket or straight-slot screwdriver e. Re-install ground wire, placing washers in original positions. P a g e 11
Re-Install Ground Wire 6. Remove cover on the new Sevcon Motor Drive Box. a. First make sure any spilled glycol coolant has been cleaned up b. Keep the screws for re-use later 7. Reconnect cables & leads P a g e 12
Re-Install Cables and Install Gland Grommets\Nuts Install Cables into Terminal Blocks and Attach Ground Wires a. AC INPUT b. SW PUMP c. MOTOR d. Shield termination method is important e. Newer Sevcon Motor Drive Box may not have the brass brush for the braided shield f. If a brass brush is not available, but is otherwise needed g. Reconnect Molex connector in reverse order of step 5 in removal instructions P a g e 13
8. Replace cover on the new Sevcon Motor Drive Box a. Use the screws you saved from Replacement step 6.b 9. Re-energize DC and AC power by normal procedure a. Remove safety tag from DC & AC circuit breakers to Seakeeper gyro b. Turn On the DC & AC circuit breakers to Seakeeper gyro 10. Re-Fill coolant system to proper level by operating Coolant Pump on manual override a. It will be necessary to add 6-10 ounces of 50/50 glycol coolant to bring system to proper level 11. Test new Sevcon Motor Drive Box by normal start-up procedure a. From main screen, verify no alarms are present and press the POWER button Power Button b. Gyro should display status bar as RPM is building. Verify a consistent rise in RPM with no alarms present. P a g e 14
c. Once status bar turns green the gyro can be unlocked by pressing the LOCK/UNLOCK button Lock/Unlock Button d. Gyro Control Display Screen should show the Gyro precessing and the Gyro is now stabilizing. 12. Ship old Sevcon Motor Control Box back to Seakeeper P a g e 15
ECN REVISION DESCRIPTION OF CHANGES DATE APPROVED 1 INITIAL RELEASE 10/27/2015 Kevin P a g e 16