INSTALLATION INSTRUCTION MERIDIAN PLUS CONTENTS TIPS BEFORE BEGINNING INSTALLATION......... 2 ZONEMANAGER...3 ZONE MANAGER ADDRESSING.................. 5 COMMUNICATIONSLOOPS...6 COMMUNICATIONS LOOP WIRING OVERVIEW..... 6 BYPASS DAMPER............................. 8 ZONEDAMPERS...9 MOUNTING...9 ZONECONTROLLERS...10 CONSTANTVOLUMECONTROLLERS...13 CONSTANT VOLUME CONTROLLER ADDRESSING................................ 15 ZONESENSORS...16 SUPPLY AIR TEMPERATURE SENSOR........... 17 RETURN AIR TEMPERATURE SENSOR........... 17 OUTSIDE AIR TEMPERATURE SENSOR.......... 17 STATICPRESSURESENSOR...17 AUXILIARY RELAY BOARD FOR ZONE CONTROLLERS...18 ZONE CONTROLLER RELAY EXPANSION BOARDOPERATION...18 COMMLINKIIINTERFACE...18 APPENDIX................................... 19 TO OTHER Meridian Plus ZONE MANAGERS Meridian Plus ZONE MANAGER TYPICALLY MOUNTED IN THE HVAC UNIT MERIDIAN PLUS SYSTEM MANAGER 036-33035-001 Rev. A (0401)
TIPS BEFORE BEGINNING INSTALLATION Take a few moments to review the following before beginning installation of the Meridian Plus System. Familiarize yourself with all system components and review all documentation. Pay special attention to Cautions and Warnings since these may keep you from experiencing unnecessary problems. Before installing zone dampers, be sure to tag each damper with its appropriate location. A set of labels is included with this manual. It is also best to set the zone controller address switches before mounting in drop ceilings. Use the Zone Address Worksheet to list all zone locations. This will assist you greatly when setting up the system. Be sure and install all wiring according to local, state, and national codes. Pay close attention to communication wiring since the most common mistakes are made in this area. Polarity is the most important rule. Make notes on your wiring diagrams as to which color wire you will be using on each terminal. NOTE Meridian Plus systems use two separate types of communications loops. The Network Loop connects only to the Zone Managers and the CommLink II. The Local Loops connect between the Zone Manager and the Zone Controllers for that HVAC unit. Each Zone Manager has its own Local Loop for connection to associated Zone Controllers and any additional Constant Volume units and the System Manager. Do not connect zone controllers, constant volume units or the system manager to the network loop! When in doubt - ask! Contact your local Meridian distributor if you have any questions. The only dumb questions are the ones you don t ask. Remember - each electronic device contains only one puff of smoke. If you release it, you have voided the warranty! So please be careful and pay attention Meridian Plus ZONE MANAGER TYPICALLY MOUNTED TO OTHER Meridian Plus ZONE MANAGERS MERIDIAN PLUS SYSTEM MANAGER FIGURE 1: SYSTEM OVERVIEW 2 Installation Instruction - Meridian Plus
ZONE MANAGER The Zone Manager may be installed in any convenient protected location. Observe the recommended environmental limitations for the Zone Manager (see Technical Data section of the product data sheet) when choosing a location. The Zone Manager may be mounted without removing the controller from the mounting plate. The unit is mounted by four (4) screws in the corners. Select the correct screws or other fasteners for the type of mounting material being utilized. FIGURE 2: MERIDIAN PLUS ZONE MANAGER Installation Instruction - Meridian Plus 3
MERIDIAN PLUS ZONE MANAGER FIGURE 3: ZONE MANAGER WIRING Use extreme care not to damage any of the electronic components while mounting the backplate. Mark the holes then remove the Zone Manager before drilling. Do not allow metal shavings to fall onto the circuit boards. 4 Installation Instruction - Meridian Plus
The Zone Manager requires the following electrical connections: 18 Gauge minimum unless otherwise noted. -24 VAC Supply Voltage 2 Conductors -Communications Loops 2 Conductor twisted pair with shield (Belden #82760 or equivalent) -Supply Air Temperature Sensor (24 ga. Min.) 2 Conductors -Return Air Temperature Sensor (24 ga. Min.) 2 Conductors -Outside Air Temperature Sensor (24 ga. Min.) 2 Conductors -Supply Static Pressure Sensor (24 ga. Min.) 3 Conductors -Bypass Damper 4 Conductors -HVAC Unit Control Wiring R-Common G-Fan Y1-Cool 1 Y2-Cool 2 W1-Heat 1 W2-Heat 2 -Additional wires depending on stages Y3 through Y6 (optional board required) W3 through W6 (optional board required) ZONE MANAGER ADDRESSING TIP After making all electrical connections it is advised to unplug all terminal blocks on the Zone Manager until you are ready to begin the checkout procedure. This may help to prevent damage if wiring errors occur elsewhere in the system during installation or start-up. FIGURE 4: ZONE MANAGER ADDRESS SWITCH SETTING Installation Instruction - Meridian Plus 5
COMMUNICATIONS LOOPS Both the Network Loop and the Local Loops are two wire shielded RS-485. The loops are best connected in daisy chain configuration, meaning the loops are connected from one controller to another. It is not necessary to sequentially address the zone controllers in relation to their location on the loop. Cable must be Belden No. 82760 or equivalent. TIP Incorrect wiring of the communications loop is the most common mistake made during installation. Before beginning installation, write down the wire color used on each terminal connection and consistently maintain that color code. It is recommended that a continuous wire run be made between devices. Anytime a splice is made in the cable you increase your chance of problems. NOTE Meridian Plus systems use two separate types of communications loops. The Network Loop connects only to the Zone Managers and the CommLink II. The Local Loops connect between the Zone Manager and the Zone Controllers for that HVAC unit. Each Zone Manager has its own Local Loop for connection to associated Zone Controllers and any additional Constant Volume units and the System Manager. Do not connect zone controllers, constant volume units or the system manager to the network loop! Even though the daisy chain configuration is preferred, the star configuration can also be used. If required, a combination of the two can also be used. Remember, the best comm loop wiring is the one which utilizes the minimum number of ends while using the shortest wiring path. Make sure when you are inserting wires into the terminal blocks that strands of wire do not stick out and touch the next terminal. This could cause a short or erratic operation. NOTE The loop does not have to follow the controller address sequence. COMMUNICATIONS LOOP WIRING OVERVIEW The daisy chain is the best method for running a communications loop since there is only one starting point and one ending point for each of the communications loops. (Figure 5).. If comm loop is not installed in conduit be careful to position the cable away from high noise devices like fluorescent lights, transformers, VFD s, etc. Conduit is not required for comm loop wiring unless required by local codes. 6 Installation Instruction - Meridian Plus
FIGURE 5: COMMUNICATION LOOP WIRING, DAISY-CHAIN CONFIGURATION Even though the daisy chain configuration is preferred, the star configuration can also be used. If required, a combination of the two can also be used. Remember, the best comm loop wiring is the one which utilizes the minimum number of ends while using the shortest wiring path. NOTE The loop does not have to follow the controller address sequence. If comm loop is not installed in conduit be careful to position the cable away from high noise devices like fluorescent lights, transformers, VFD's, etc. Conduit is not required for comm loop wiring unless required by local codes. Installation Instruction - Meridian Plus 7
BYPASS DAMPER The bypass damper is mounted similar to the zone dampers,infacttheonlydifferenceinmostcasesisthesize.the bypass damper should typically be sized for at least 60-70 percent of the total design CFM. More than one bypass damper may be slaved together when it is not practical to use a single large damper. As with the zone dampers it is often easier to mount the actuators before installing the bypass damper in the ceiling. Never depress the actuator clutch with power applied. Unplug the actuator cable before depressing the clutch and attempting to rotate the damper blade. See Figure 7 for damper actuator mounting instructions. If sheet metal screws are used to mount the dampers, be certain that they do not interfere with the movement of the damper blade. If the fan system has the capability of producing static pressures which could damage ductwork you must provide a manual reset, high pressure limit switch to cut-off the fan system in the event of high duct static. Do not use your Meridian System as a safety device The bypass damper should be installed as close as possible to the rooftop unit. FIGURE 6: BYPASS ACTUATOR WIRING 8 Installation Instruction - Meridian Plus
ZONE DAMPERS Generally, zone dampers come preassembled with the actuator and Zone Controller. If not, the following instructions will assist you. MOUNTING In most cases it is preferable to mount the damper actuator to the zone damper prior to mounting the damper in the ceiling. Before installing the zone damper, check for free movement of the damper blade by depressing the clutch on the damper actuator and moving the blade between it s full open and full closed positions. Any binding or incorrect adjustment should be corrected before mounting the damper. NOTE Direct acting actuators drive clockwise to open. Reverse acting actuators drive counter clockwise to open. Never depress the actuator clutch with power applied. Unplug the actuator cable before depressing the clutch and attempting to rotate the damper blade. Do not force the damper blade as this can damage the gears in the damper actuator. Zone dampers should be securely hung using either wire cradles or metal strapping. While the dampers may be hung in any position, avoid sharp kinks in flexible duct to prevent airflow restrictions. If an air flow sensor is mounted, always be sure that the tips of the sensor are pointing down. The zone dampers should be insulated when installed in non-conditionedspacestoavoidsweating and to improve energy efficiency. If sheet metal screws are used to mount the dampers, be certain that they do not interfere with the movement of the damper blade. FIGURE 7: TYPICAL ACTUATOR MOUNTING Installation Instruction - Meridian Plus 9
ZONE CONTROLLERS Generally, Zone Controllers are supplied mounted on the zone dampers. The Zone Controllers are mounted in snaptrack which is typically located on the zone dampers. Orient the board in the snap-track so that the actuator, flow sensor (optional), and auxiliary relay board (optional) cables will reach their respective connectors on the Zone Controller, if they are used. Press the board into the snap-track carefully to avoid damaging any of the electronic components on the circuit board. To remove a board from the snap-track, carefully pull one edge of the snap-track away from the board with your fingers and remove the board. TIP After making all electrical connections it is suggested that all terminal blocks on the Zone Controller be unplugged until you are ready to begin the checkout procedure. This may help prevent damage if wiring errors occur elsewhere in the system during installation or start-up. This is particularly important with the Zone Controllers since an error on one unit may prevent any of the others from working until the problem is found and corrected. Do not use any tools to pry the board loose. This will damage the board and/or the snap-track. When mounting the snap-track be sure the heads of the screws do not protrude far enough to touch the bottom of the Zone Controller circuit board. Consider serviceability of the location when mounting the Zone Controllers. They should be easily accessible to facilitate servicing. Polarity is very important when connecting power to the controllers! The grounded side of the control transformer must be connected to the terminal labeled GND on the Zone Controller. If a single transformer is used to power more than one Zone Controller you must connect GND-to-GND and 24VAC-to-24VAC on each zone controller. Failure to observe polarity will result in damage to one or more components in your system. TIP Use small stickers on the ceiling grid or tiles to help future service personnel locate system components. If you use small stickers from an office supply store, you can get different colors to code the location of various components. The Zone Controller requires the following electrical connections: 24VAC Supply Voltage Communications Loop Room Temperature Sensor Fan Terminal units / Auxiliary Heat 2 Conductors 2 Conductor twisted pair with shield (Belden #82760 or equivalent) 2 Conductors for standard sensors 3 Conductors for sensors with setpoint adjustment 2-4 Conductors see wiring diagrams for (Optional) Aux. Relay board 10 Installation Instruction - Meridian Plus
FIGURE 8: ZONE CONTROLLER WIRING Installation Instruction - Meridian Plus 11
Set the Zone Controller Address Switch following the supplied addressing instructions. NOTE Ignore any markings or numbers on the switch. Use this chart! Incorrect addressing is the number one cause of communication problems. Check the addressing carefully. Remember, the Zone Controller only reads the switch during a power-up. If the address switch is changed, the unit must be turned OFF then ON before the new setting will be recognized. FIGURE 9: ZONE CONTROLLER ADDRESS SWITCH SETTINGS 12 Installation Instruction - Meridian Plus
CONSTANT VOLUME CONTROLLERS The Constant Volume Controller may be installed in any convenient protected location. Observe the recommended environmental limitations for the Constant Volume Controller (see the Technical Data section of the product data sheet) when choosing a location. The Constant Volume Controller may be mounted without removing the controller from the mounting plate. The unit is mounted by four (4) screws in the corners. Select the correct screws or other fasteners for the type of mounting material being utilized. FIGURE 10: CONSTANT VOLUME CONTROLLER Installation Instruction - Meridian Plus 13
FIGURE 11: CONSTANT VOLUME CONTROLLER WIRING Use extreme care not to damage any of the electronic components while mounting the backplate. Mark the holes then remove the CV Controller before drilling. Do not allow metal shavings to fall onto the circuit boards. TIP After making all electrical connections it is advised to unplug all terminal blocks on the CV Controller until you are ready to begin the checkout procedure. This may help to prevent damage if wiring errors occur elsewhere in the system during installation or start-up. 14 Installation Instruction - Meridian Plus
The Constant Volume Controller requires the following electrical connections: 18 Gauge minimum unless otherwise noted. -24VAC Supply Voltage -Communications Loop -Supply Air Temperature Sensor -Room Air Temperature Sensor -Outside Air Temperature Sensor 2 Conductors 2 Conductor twisted pair with shield (Belden #82760 or equivalent) (24 ga. Min.) 2 Conductors (24 ga. Min.) 2 Conductors for standard sensor 3 Conductors for sensors with setpoint adjustment (24 ga. Min.) 2 Conductors -HVAC Unit Control Wiring R - Common G - Fan Heat / Cool Stage 1, 2, 3, & 4 CONSTANT VOLUME CONTROLLER ADDRESSING FIGURE 12: CV CONTROLLER ADDRESS SWITCH SETTING Installation Instruction - Meridian Plus 15
ZONE SENSORS The zone sensor uses a patented flush mount design to isolate the temperature sensing element from the housing which mounts flush with the wall surface. Zone sensors should be located on an inside wall away from direct sunlight or heat producing equipment such as computers, copiers, etc. Such devices can adversely affect the accuracy of the sensor. Although the sensor eliminates most of the effects of thermal coupling to the walls, try to avoid walls which retain large amounts of thermal energy (such as marble or steel). Walls containing either cold or warm air currents should also be avoided whenever possible. Avoid locating the sensor in dead air areas of a room. This will result in slow response to temperature changes in the space. Mount the sensor approximately 50-60 inches from the floor for best results. The zone sensor is designed to mount vertically in a standard 2 by 4 inch electrical box. The sensor may be mounted directly into the drywall where electrical codes do not require low voltage wiring to be enclosed in conduit. A template is supplied with the sensor to facilitate cutting a hole of the correct size. TIP Be careful when cutting the hole for the sensor or the plastic bezel of the sensor may not completely cover the opening. Connect the terminal labeled GND on the zone sensor to the terminal labeled GND on the Zone Controller terminal block for the TEMP SENSOR. Connect the terminal labeled TMP on the zone sensor to the terminal labeled TEMP on the Zone Controller terminal block for the TEMP SENSOR. If the zone sensor has a setpoint adjust slider, then connect the sensor terminal labeled AUX to the Zone Controller AUX terminal block labeled AUX1. TIP If sensors must be installed on walls which are solid and cannot be penetrated, surface mounted boxes and raceway can be purchased from your local electrical distributor. Room Sensor with Override And Adjustable Setpoint NORMAL OVR W A R M E R C O O L E R TB TMP GND AUX ADJUSTABLE SETPOINT Zone Controller AUX +VS AUX1 GND AUX 2 GND OVERRIDE TEMP GND T'STAT FIGURE 13: ZONE SENSOR WIRING 16 Installation Instruction - Meridian Plus
SUPPLY AIR TEMPERATURE SENSOR The supply air temperature sensor should be located as close to the rooftop unit discharge as possible for best response and mounted upstream of the bypass damper for best results. Locate the sensor in the center of the widest part of the duct. Use the supplied template and a 5/16" drill to make a hole for the sensor. Install the gasket over the probe and mount securely to the duct using the supplied sheet metal screws. Be sure the gasket is compressed to provide an air tight seal. For best accuracy, apply insulation on the outside of the duct, over the sensor. This will help prevent thermal gradients from affecting the sensor. RETURN AIR TEMPERATURE SENSOR The return air temperature sensor should be located as close to the rooftop unit return air intake as possible. Avoid locations which will be exposed to extreme outside temperatures. Locate the sensor in the center of the widest part of the duct. Use the supplied template and a 5/16" drill to make a hole for the sensor. Install the gasket over the probe and mount securely to the duct using the supplied sheet metal screws. Be sure the gasket is compressed to provide an air tight seal. Do not mount the return air sensor in the mixed air section. This will cause an error in the reading. For best accuracy, apply insulation on the outside of the duct, over the sensor. This will help prevent thermal gradients from affecting the sensor. OUTSIDE AIR TEMPERATURE SENSOR The outside air sensor must be located where it will not be affected by direct sun or heat producing equipment. Mounting under the eve of a roof is often a good choice. NOTE All sensors utilize the same type thermistor sensor sensing element. Refer to Appendix Table 1, TEM- PERATURE SENSOR RESISTANCE CHART, for troubleshooting sensor problems. STATIC PRESSURE SENSOR The static pressure sensor is designed to be mounted at the controller, or on the ductwork near the pickup tube, and may be connected via its modular plug. If the sensor is mounted on the ductwork, the modular plug must be cut off and 3-conductor wire spliced onto the sensor leads. The controller has a terminal block which is paralleled with the modular jack to allow connection when this method is utilized. Mount the static pressure sensor on a vertical surface with the tube tips pointing downward. Avoid any kinks or sharp bends in the tubing which runs from thepickuptubetothesensor. The plastic housing on the sensor is electrically conductive. Avoid contact with any electrical components. It is acceptable to mount the sensor on grounded sheet metal such as ductwork, electrical panels, etc. Use extreme care when mounting the sensor to avoid damage to the plastic housing. Do not over tighten the mounting screws! Do not use mounting screws which are too large for the holes! Complaints of inaccurate outside sensor readings are very common and can almost always be shown to be the result of poor sensor location NOTE Refer to Appendix Table 2 for instructions concerning proper location of the static pressure sensor. Installation Instruction - Meridian Plus 17
Relay contacts are rated for 24VAC pilot duty only! Do not apply voltages higher than 24VAC. ZONE CONTROLLER RELAY EXPANSION BOARD OPERATION Relay#1-ParallelFan If the zone is in cooling mode or vent mode, theparallel fan can activate anytime the zone temperature drops 0.5 F below the heating setpoint. It de-activates when the temperature rises above the heating setpoint. FIGURE 14: STATIC PRESSURE SENSOR WIRING AUXILIARY RELAY BOARD FOR ZONE CONTROLLERS An optional auxiliary relay board is available for the Zone Controllers. This board provides additional outputs for the following applications: Parallel Fan Box Heat Auxiliary Heat (typically perimeter type) Series Fan The board comes shipped with a modular cable which plugs directly into the Zone Controller connector marked Expansion. After connecting the board, the system will need to be powered OFF then ON for the system to recognize the presence of the relay board.. Relay#2-BoxHeat If the zone is in cooling mode or vent mode the box heat can activate anytime the zone temperature drops 1.5 F below the heating setpoint. It de-activates when the temperature rises to within 1.0 F of the heating setpoint. Box heat is not allowed to activate in the heating mode when there is hot air being supplied by the air handler. This output was intended to allow zone re-heat while the Zone Manager is satisfying cooling demands in other zones. Relay#3-AuxHeat In the occupied mode, theaux heat can activate anytime the zone temperature is 0.5 F below the aux heat setpoint. It de-activates when the temperature rises 0.5 F above the aux heat setpoint. In the unoccupied mode, the aux heat uses the unoccupied heating setpoint with the same deadband values mentioned above. This prevents the zone from maintaining the same aux heat setpoint at night that it does during the daytime. This output was intended to allow zone heating, to augment thenormalheatingmodeandalsotoallowazonetoattempt to satisfy its own heating needs before creating a heating demand at the Zone Manager. Relay#4-SeriesFan The series fan runs anytime the main fan is running. This includes occupied and unoccupied modes. The fan can only start running when the zone damper is closed, so it first makes sure the damper is closed, before starting the fan. COMMLINK II INTERFACE The CommLink II Interface provides on site computer hookup or modem interface for remote communications. The Commlink II is wired as shown in Figure 16. FIGURE 15: AUXILIARY RELAY BOARD LAYOUT 18 Installation Instruction - Meridian Plus
Locate the CommLink near the computer or modem. The cable connections between the CommLink II and the computer or modem should be kept to less than twenty-five feet. The CommLink II comes complete with computer and modem cables, and a plug-in power supply. FIGURE 16: COMMLLNK INTERFACE WIRING Installation Instruction - Meridian Plus 19
APPENDIX Table 1: Temperature Sensor Resistance Chart Table 1: Temperature Sensor Resistance Chart TEMPERATURE F RESISTANCE Ω* VOLTAGE AT INPUT* TEMPERATURE F RESISTANCE Ω* VOLTAGE AT INPUT* -10 93,333 4.620-5 80,531 4.550 0 69,822 4.474 5 60,552 4.390 10 52,500 4.297 15 45,902 4.200 20 40,147 4.095 25 35,165 3.982 30 30,805 3.862 35 27,140 3.737 40 23,874 3.605 45 21,094 3.470 50 18,655 3.330 52 17,799 3.275 54 16,956 3.217 56 16,164 3.160 58 15,385 3.100 60 14,681 3.042 62 14,014 2.985 64 13,382 2.927 66 12,758 2.867 68 12,191 2.810 69 11,906 2.780 70 11,652 2.752 71 11,379 2.722 72 11,136 2.695 73 10,878 2.665 74 10,625 2.635 75 10,398 2.607 *Notes: 78 9,711 2.520 80 9,302 2.465 82 8,893 2.407 84 8,514 2.352 86 8,153 2.297 88 7,805 2.242 90 7,472 2.187 95 6,716 2.055 100 6,047 1.927 105 5,453 1.805 110 4,923 1.687 115 4,449 1.575 120 4,030 1.469 125 3,656 1.369 130 3,317 1.274 135 3,015 1.185 140 2,743 1.101 145 2,502 1.024 150 2,288 0.952 1. Use the resistance column to check the thermistor sensor while disconnected from the controllers (not powered). 2. Use the voltage column to check sensors while connected to powered controllers. Read voltage with meter setondcvolts.placethe"-"(minus)leadongndterminal and the "+" (plus) lead on the sensor input terminal being investigated. If the voltage is above 5.08 VDC, then the sensor or wiring is "open". If the voltage is less than 0.05 VDC, the sensor or wiring is shorted. 76 10,158 2.577 20 Installation Instruction - Meridian Plus
Table 2: Static Pressure Sensor Location Information Preferred Location If the trunk ducts are properly sized for minimum pressure drop, the location of the static pickup probe is not particularly critical. It should ideally be located at right angles to the airflow in a straight section of the supply duct approximately 2/3 the distance of the total length of the supply duct. Also the probe should be located not less than 3 duct diameters downstream and 2 duct diameters upstream of any elbow or takeoff. SUPPLY TEMP SENSOR FAN BYPASS RETURN AIR SENSOR RETURN STATIC PRESSURE PICKUP 3D MIN. 2D MIN. Less Than Ideal, But Acceptable Since the "ideal" location is often difficult to find in an installation, a location in the main trunk where the tip is not in a "negative pressure area" (e.g. just downstream of the inside curveofanelbow)oranareawherethetubeopeningis directly impacted by the velocity of the supply air. Least Desirable, But Acceptable If the supply duct comes directly from the unit and immediately splits in opposite directions, the pressure pickup should be located ahead of the split, or as close to it as possible, even if the bypass damper(s) are located downstream of the split. TO ZONES TEE PICKUP PRESSURE STATIC G S SENSING LINES ARE EQUAL SENSOR TEMP SUPPLY BYPASS TO ZONES RETURN FAN Subject to change without notice. Printed in U.S.A. 036-33035-001 Rev. A (0401) Copyright by Unitary Products Group 2001. All rights reserved. Supersedes: Nothing Unitary 5005 Norman Product York OK Group Drive 73069