Orion VAV-Zone User Manual

www.orioncontrols.com

VAV/Zone Contr oller

Technical Guide

Table Of Contents

Controller Overview ........................................................................................................................................ 3

Features...................................................................................................................................................................................... 3

Controller Inputs and Outputs ........................................................................................................................ 5

VAV/Zone Controller Analog Inputs ............................................................................................................................................ 5

Other Controller Connections ..................................................................................................................................................... 5

Optional - Expansion Board Outputs .......................................................................................................................................... 5

Controller Installation & Wiring ...................................................................................................................... 6

General ....................................................................................................................................................................................... 6

Controller Mounting .................................................................................................................................................................... 6

Important Wiring Considerations ................................................................................................................................................ 6

Modular Devices - Transformer Sizing ....................................................................................................................................... 7

Slaved Zone Damper Wiring ...................................................................................................................................................... 8

Expansion Board Installation & Wiring .......................................................................................................... 9

Wiring Considerations ................................................................................................................................................................ 9

Start-up & Commissioning ............................................................................................................................ 11

General ......................................................................................................................................................................................11

Controller Addressing ................................................................................................................................................................11

Power Wiring ............................................................................................................................................................................ 12

Initialization............................................................................................................................................................................... 12

Programming The Controller .................................................................................................................................................... 13

Sequence Of Operations ............................................................................................................................... 14

Initialization............................................................................................................................................................................... 14

VAV/Zone Configuration & Setup ............................................................................................................................................. 14

Scheduling ................................................................................................................................................................................ 15

Modes Of Operation ................................................................................................................................................................. 15

Damper Positions ..................................................................................................................................................................... 16

Occupied Mode Sequences ..................................................................................................................................................... 16

Unoccupied Mode Sequences .................................................................................................................................................. 17

Damper Control ........................................................................................................................................................................ 19

Tenant Override Logs ............................................................................................................................................................... 20

Zoning....................................................................................................................................................................................... 20

Alarm Detection And Reporting ................................................................................................................................................ 21

Internal Trend Logging.............................................................................................................................................................. 21

Force Modes or Overrides ........................................................................................................................................................ 21

Troubleshooting ............................................................................................................................................ 22

Using LEDs To Verify Operation ............................................................................................................................................... 22

Other Checks ............................................................................................................................................................................ 22

WattMaster Controls Inc. 8500 NW River Park Drive · Parkville , MO 64152 Toll Free Phone: 866-918-1100 PH: (816) 505-1100 · FAX: (816) 505-1101 · E-mail: mail@wattmaster.com Visit our web site at www.orioncontrols.com Form: OR-VAVZ-TGD-01C Copyright 2006 WattMaster Controls, Inc. AAON® is a registered trademark of AAON, Inc., Tulsa, OK. WattMaster Controls, Inc. assumes no responsibility for errors, or omissions. This document is subject to change without notice.

Controller Over view

T ec hnical Guide

Features

VAV/Zone Controller

This manual applies to the VAV/Zone controller that is included in the following Orion products:

OE742-XX-VAVZ VAV/Zone Package

Pressure Dependent

OE744-XX-VAVZ VAV/Zone Package

Pressure Independent

OE520-XX VAV/Zone Round Damper

Assembly - Pressure Dependent

OE521-XX VAV/Zone Round Damper

Assembly - Pressure Independent

OE736-XX VAV/Zone Rectangular Damper Kit

The VAV/Zone Controller is used for controlling airflow and operation of VAV or Zoning terminal units. It is a programmable digital controller which allows for program setpoints to be stored in non-volatile memory. The controller is connected to a room sensor via a modular cable assembly which monitors space temperature allowing the VAV/Zone controller to modulate a damper in response to space temperature, duct temperature and airflow requirements in the controlled space.

The VAV/Zone controller has four integral modular jacks for connection to the actuator, airflow sensor (for pressure independent applications), room sensor and relay or analog expansion boards, via modular cables. Molex cable connections are provided for the 24 VDC power and system communications. A quick connect terminal connector is also supplied for connection of the Modular Service Tool to facilitate pro-

gramming of the controller. The controller has an on-board dip switch provided for board addressing.

The VAV/Zone controller is provided with two relays for tri-state control of the damper actuator. All outputs and the relay common are electrically isolated from all other circuitry on the board. All relay outputs are supplied with transient suppression devices across each set of contacts to reduce EMI and arcing. The relay output contacts are rated for pilot duty control of a maximum of 2 Amps @ 24 VAC or 24 VDC. The actuator connects via a modular cable to the board and provides the VAV/Zone controller with feedback monitoring for precise positioning of the actuator.

OE322 Output Expansion Boards

The OE322, 3 Relay with Analog Output Expansion board is used in conjunction with the VAV/Zone Controller board to allow for control of VAV and Zone terminal units, including series and parallel fan terminal units with up to 3 stages of electric heat or modulating hot water heat. The OE322, 3 Relay with Analog Output Expansion board provides 3 relay outputs for pilot duty switching control, and 1 Analog output for control of a 0-10 V modulating hot water valve.

The OE322 Output Expansion board connects to the VAV/Zone controller board by means of a modular cable provided with the expansion board. Power is supplied to the board by means of this modular cable. Screw terminals are provided for connection of field wiring to the relay and analog outputs.

The relay outputs are N.O. contacts with one common terminal. All outputs and the relay common are electrically isolated from all other circuitry on the board. All relay outputs are supplied with transient suppression devices across each set of contacts to reduce EMI and arcing. The relay output contacts are rated for pilot duty control of a maximum of 2 Amps @ 24 V AC or 24 VDC. The analog output provides a 0 – 10 VDC modulating signal output into a 1K ohm minimum load.

6.30”

R21

R22

CX7

ACTUATOR

PJ2

R9R8R7R6R5

C9 C10 C11

PJ3

SCAN

K1 K2

R10

R14

R15

REC

R19

R20

R18

C13

PWR

GND

AIN

RV1

AUX

TB2

OUT

R33

R36

VR1

R37

R23

HAND HELD

R32

C14

CX8

R16

R35

4.00"

EEPROM

VAVZ CONTROLLER

YS101854 REV.2

CX9

PAL

CX10

CX11

RN1

PJ1

ADD

JP1

CX3

WDOG

CX4

JP2

R38

C12

R24

R25

U10

AIRFLOW SPACE SENSOR

U11

PJ4

NET

32162

CX1

SW1

CX6

EPROM

EXPANSION

Figure 1: V AV/Zone Controller Dimensions

V AV/Zone Controller 3

Technical Guide

Controller Over view

Figure 2: OE322 Output Expansion Boards

RAM Chip

Snap Track For Controller Mounting

Air Flow Sensor Modular Connector

Space Temp Sensor Modular Connector

AUX- Supply Air Sensor Wiring Terminals (When Used)

Power LED

Communications Driver Chip

EPROM Chip

C14

PAL Chip

CX11

U11

PJ4

PJ3

TB2

AUX

R33

VR1

R32

PAL

CX10

EPROM

RN1

U10

R24 R25

AIRFLOW

SPACE SENSOR

AIN

GND

PWR

RV1

C12

R22

R21

CX7

R14

R15 R19

C13

CX8

R20

R18

R35 R36

R23

R37

Typical Pin 1 Indicator

VAVZ CONTROLLER YS101854 REV. 2

CX9

CX6

JP2

CX4

R38

C9 C10 C11

SCAN

REC

R16

HAND HELD

CX3

WDOG R3

R4 R5 R6 R7 R8 R9

R10

OUT

EEPROM

CX1

SW1

NET

8 4 2

ADD

JP1

Address Switch (Set Between1&58)

Jumper For Pressure

Independent Airflow

PJ1

Operation. Must Be On

EXPANSION

For High Velocity Terminal Configurations And Removed For Low Velocity Applications

PJ2

ACTUATOR

Expansion Board Modular Connector

Damper Actuator Modular Connector

“SCAN” LED

“REC” LED

Damper Actuator Positioning Relay “Open”

Damper Actuator Positioning Relay “Close”

Mini DIN Connector Connect Modular Service Tool Here For Programming

Figure 3: V AV/Zone Controller Component Locations

Modular Cable Connectors Connects To Modular Cable From Power/Com Board And Connects To Next Controller On Loop Supplies 24 VAC Power and RS-485 Communications In And Out Of Controller

V AV/Zone Controller

Controller Inputs and Outputs

T ec hnical Guide

The following inputs and outputs are available on the VAV/Zone controller and the OE322 Output Expansion Board that can be added by connecting it to the main controller board expansion port. For component locations of the inputs on the VAV/Zone Controller see Figure 3. For wiring of inputs and outputs see Figure 4 thru 9.

V AV/Zone Controller Analog Inputs

Input #1: Space Temperature

The Modular Room Sensor that reads space temperature is attached to this input. The Modular Sensor connects via a modular cable to the VAV/Zone controller. If the optional push-button override sensor is installed, this input will detect user overrides from unoccupied back to occupied operation for a user adjustable amount of time.

Input #2: Airflow Sensor

If the VAV/Zone Controller is to be configured for pressure independent operation, you need to install the OE274 Airflow Sensor and connect the modular plug from the pressure sensor to this input. The pressure signal from the Airflow Sensor is used for CFM (airflow) calculations. If an OE274 Airflow Sensor is attached to this input, the VAV/ Zone controller will automatically detect this and switch to pressure independent operation. If the sensor is not attached or becomes defective, the controller automatically reverts to pressure dependent operation. When the VAV/Zone controller is used for pressure independent applications, the JP2 jumper must be “ON” for high velocity systems and “OFF” for low velocity systems. Typically VAV systems are medium to high velocity and voting systems are low velocity . As a rule of thumb, if the velocity through the terminal unit is below 1500 FPM, remove the jumper and if above 1500 FPM, leave the jumper on. If it is a low velocity system, in addition to removing the jumper, the configuration option: “Is This a Voting System” must be YES, even on a VAV system. If the CFM is greater than the values listed for the terminal inlet size above, the JP2 jumper on the VAV/Zone controller must be installed and the system must be configured as a “Non-Voting System. If this is a high velocity voting system the box must be configured as a” voting box” but the system must be configured as “non-voting system” in order for the airflow sensor to read correctly . See Figure 3 for jumper location on board. See Table 1 for low velocity inlet CFM informa- tion.

Maximum Inlet CFM for Low Velocity (1500 FPM)

Inlet Size

6” Dia. 260 8” Dia. 500 10” Dia. 775

12” Dia . 1100 14” D ia. 1550 16” Dia. 2025

Notes:

1.) These va lues are averages and will vary between terminal unit manuf actu rers.

Table 1: Maximum Inlet CFM for Low Velocity

Input #3: Aux - Supply Air Temperature Sensor

A Supply Air Temperature Sensor can be connected to these terminals. It should be mounted in the supply duct close to the terminal unit where the VAV/Zone controller is installed. This sensor can be used for monitoring purposes or in place of the Supply Air Temperature Broadcast from the VCM Controller.

Note: All temperature sensors must be Thermistor Type III.

JP2 Jumper Removed

Box

CFM

Inlet Size

Box

CFM

Inlet Size

Box

CFM

Other Controller Connections

Expansion Board Modular Connector

This modular connector is used to connect the optional OE322 Output Expansion Board to the VAV/Zone controller. These boards are only required when electric or hot water heating and/or fan terminal control is required. The expansion boards are not required for cooling only terminal units.

Actuator Modular Connector

This modular connector is used to connect a modular cable from the VAV/Zone controller to a tri-state actuator.

Power/Comm Modular Connectors

These two modular connectors, (labeled P1 & P2) are used to connect modular cables from the Power/Comm board that supplies 24 V olt power and communications to the controller and to supply 24 Volt power and communications to the next controller on the local loop.

Modular Service Tool DIN Connector

This connector is used to connect a cable between the Modular Service T ool and the VA V/Zone controller for programing and configuration of the VAV/Zone controller.

Optional - OE322 Expansion Board

As previously stated when control of a fan or if heating is required the OE322 Output Expansion board must be used.

Relay Output #1 - Fan Enable

The first expansion relay on the Output Expansion boards is used for enabling the fan for Series or Parallel Fan Terminal Units.

Relay Output #2 - Stage 1 Heating

If you have at least one stage of auxiliary heating, this is the relay used to energize the 1st stage of terminal unit heating. This heating stage can either be used with electric heat or On/Off hot water valve control.

Relay Output #3 - Stage 2 Heating

If you have two stages of auxiliary heating, this relay controls the 2nd stage of electric heat. For 3 stage heating, this relay output would be energized for both the 2nd and 3rd stage of heat. See the following section for more information regarding 3 stage heating applications.

3 Stage Heating Applications

If three stages of electric heat are configured, relays #2 and #3 will stage in a staggered sequence. This allows you to achieve 3 stages of heating using only relays #2 and #3. Each of the 3 heating elements should be sized for 1/3 of the total KW output required. Both the 2nd and 3rd stage heating contactors (C2 & C3) must be connected to Relay Output #3. See Table 2 for relay sequencing information.

Stage No. Relay Output #2 Relay Output #3

#1 ON (C1) OFF (C2 & C3) #2 OFF (C1) ON (C2 & C3) #3 ON (C1) ON (C2 & C3)

Table 2: Relay Sequencing For 3 Stage Heating

24 VDC Power Terminals (+V & GND)

These terminals can supply 24 Volts DC for a 24 VDC hot water valve actuator if desired. This output is rated at 12 Watts maximum load.

Analog Output

If you are using hot water or steam heating via a modulating steam or hot water valve, this output can supply a 0-10 Volts DC signal for proportional control of the valve.

V AV/Zone Controller

Technical Guide

Controller Inputs and Outputs

Airflow Probe & Sensor

(For Pressure Independent Applications Only)

Airflow

Room Sensor

A R M E R

NORMAL

C O O

OVR

L E R

Supply Air Temperature Sensor

(See Note 3)

Locate In Supply Duct

Near Zone Damper

Notes:

1.) All wiring to be in accordance with local and national electrical codes and specifications.

2.) Use Orion prefabricated modular cables for connection between the VAV/Zone controller, the Power/Comm Board and between each VAV/Zone controller on the loop.

3.)The Supply Air Sensor is not required when the VAV/Zone Controller is connected to an Orion VAV/CAV Unit Controller board. A global supply air temperature is broadcast by the VAV/CAV Unit Controller. The Supply Air Sensor is only required if the VAV/Zone Controller is required to operate as a “Stand Alone” controller. It can also be used on VAV/Zone controllers that have reheat to monitor the box discharge air temperature.

VAV/Zone Controller Board

R25

PJ4

AIRFLOW

PJ3

SPACESENSOR

TB2

AIN

GND

Power/Comm Cable To Next VAV/Zone Controller or Power/Comm Distribution Board

Zone Actuator

SW1

NET

16 8 4 2 1

ADD

PJ1

EXPANSION

PJ2

ACTUATOR

To Optional Relay Expansion Board

Power/Comm Cable From Power/Comm Distribution Board Or Previous VAV/Zone Controller

Figure 4: V AV/Zone Controller Wiring

Controller Installation & Wiring

General

Correct wiring of the VAV/Zone controller is the most important factor in the overall success of the controller installation process. The VAV/ Zone controller wiring has been simplified by the use of modular connectors and prefabricated modular cables.

Controller Mounting

If the Round Zone Dampers or Rectangular Zone Damper Kits were purchased from WattMaster, the controller and actuator are factory mounted and wired in the damper control enclosure. If your VAV/Zone controllers are pressure independent, an airflow probe and pressure sensor will also be factory mounted and wired.

Most terminal unit manufacturers will offer the option of factory mounting the Orion controls in their terminal units for an additional charge. An installation worksheet and instructions are available for the Orion V AV/Zone controller package which can be shipped with the V AV/Zone control(s) to the terminal unit manufacturer to simplify third party factory mounting and wiring of the controller.

When the VAV/Zone controller is to be field mounted, it is important to mount the controller in a location that is free from extreme high or low temperatures, moisture, dust and dirt. The VAV/Zone controller board must be mounted within 10” of the damper actuator in order for the actuator cable to extend between the controller and the actuator.

Be careful not to damage the electronic components when mounting the controller. Remove the controller from its snap track mount. Mark the control enclosure base using the snap track as a template. Drill pilot holes in the enclosure base and secure the snap track to it using sheet metal screws. Do not allow metal shavings to fall onto the circuit board. Reattach the controller to the snap track. Mount the damper actuator to the damper shaft following the instructions supplied with the damper actuator.

Important Wiring Considerations

Please carefully read and apply the following information when wiring the VAV/CA V controller. See Figur e 4 for VA V/Zone controller wiring diagram.

1. Size and wire the Power/Comm Board transformer per the instructions. Failure to size the transformer and/or wire the Power/Comm board correctly may cause the VAV/Zone controllers to operate erratically or not at all. See Figure 5 for wiring and transformer sizing information.

2. If a Supply Air Sensor is to be connected, the minimum wire size used should be 24 gauge.

3. Do not pry on the connectors when connecting or disconnecting the modular cables. Be sure to push in on the connector release clip and then pull straight up.

V AV/Zone Controller

16 Devices At 6 VA = 96 VA Use 100 VA Transformer

6 Devices Maximum Per Branch Circuit

T ec hnical Guide

13 Devices At 6 VA = 78 VA Use 80 VA Transformer

Power/Comm

Board

120 / 24VAC

100 VA

Transformer

Minimum

See Warning

Note Below

12 Devices At 6 VA = 72 VA Use 75 VA Transformer

120 / 24VAC

75 VA

Transformer

Minimum

See Warning

Note Below

Power/Comm

Board

Power/Comm

Board

120 / 24VAC

80 VA

Transformer

Minimum

See Warning

Note Below

Total length of all modular cables used on each branch ( A to B) cannot exceed 240 Ft.

6 Devices Maximum Per Branch Circuit

6 Devices At 6 VA = 36 VA Use 40 VA Transformer

120 / 24VAC

40 VA

Transformer

Minimum

See Warning

Note Below

Power/Comm

Board

Total length of all modular cables used on each branch ( A to B) cannot exceed 240 Ft.

Figure 5: V AV/CAV Controller Transformer Sizing

Modular Devices - Transformer Sizing

Modular devices include the VAV/Zone Controller, Modular System Manager & MiniLink Polling Device. All of these devices connect to each other and a Power/Comm Board using prefabricated modular cables. When sizing transformers for these devices it is important to design your layout so that the fewest number of Power/Comm distribution boards and the least number of transformers can be used.

In order to simplify wiring design and layout with modular devices the following rules apply:

1. Power/Comm Board maximum transformer size = 100 VA. This is due to the board circuitry and fusing. Each modular device is to be calculated at 6 VA. This allows for a maximum of 16 devices per Power/Comm board. If more than 16 devices are required, multiple Power/Comm boards must be used. Any Slaved Zone actuators used are considered a modular device and must be accounted for at 6 VA. each. They also must be included in the branch circuit maximum quantity of 6. See rule #2 below.

2. No more than 6 modular devices allowed per branch circuit. (Each Power/Comm board has 4 branch circuits available on the board )

3. The longest total run per branch circuit is 240 Ft. This is due to voltage drop on the prefabricated cable. If cable runs longer than 240 Ft. are required, additional Power/Comm board(s) can be used. Each Power/Comm Board connected in series with the first Power/Comm Board would allow for an additional 240 Ft. of modular cable to be added to the total cable run length.

See Figure 5 for information and some examples of transformer sizing and branch circuit design.

Warning: Do not ground the 24 V transformer that is to be

used with the Power/Comm boards. Grounding of the transformer will damage the Power/Comm board and all boards connected to it. A separate transformer must be used for each Power/Comm board. No exceptions. Do not connect any other devices to the transformer used for the Power/Comm board.

V AV/Zone Controller

Technical Guide

Controller Installation & Wiring

HZ000095

EXPANSION

ACTUATOR

PJ2PJ1

(OE324) ZONE CONTROLLER BOARD

OE520, OE736, OE742

SLAVED- ZONE ACTUATOR #2

(WHEN USED)

OE523, OE738, OE282-03

ZONE ACTUATOR #1

(MASTER)

OE282

HZ000095

MODULAR CABLE

SLAVED-ZONE ACTUATOR #1

1 10 0

OE523, OE738, OE282-03

MODULAR CABLE

(PL101824) BYPASS AND

OE267

SLAVE INTERFACE CARD

OPEN

TB1

GND

FDBK

OPEN

GND

PJ2

FROM ZONE

CONTROLLER

TB2

PJ1

TOACTUATOR

LD2

OPEN

SLAVEINTERFACE

YS101824

LD1

BYPASSAND

OE282 OE282

MODULAR

CABLE

(PL101824) BYPASS AND

SLAVE INTERFACE CARD

TOACTUATOR

BYPASSAND

SLAVEINTERFACE

YS101824

PJ1

GND

OPEN

TB2

OPEN

FROM ZONE

CONTROLLER

PJ2

LD2

LD1

FDBK

GND

TB1

OPEN

HZ000095

NOT USED FOR THIS APPLICATION

(PL101824) BYPASS AND

SLAVE INTERFACE CARD

Figure 6: Slaved Zone Wiring & Connection Diagram

Slaved Zone Damper Wiring

For large zones it may be necessary to have more than one air damper controlled by a VAV/Zone controller and its associated space sensor. The Orion system allows for connecting up to two additional slaved zone dampers to the master VAV/Zone controller. Slaving is not avail-

able for pressure independent damper applications.

Note: Each slaved actuator is considered a modular device rated

at 6 VA each. This 6 VA load must be included in the transformer sizing and branch circuit calculations for the Power/Comm board. See the previous section regarding transformer sizing of the Power/Comm board for complete information.

MODULAR

CABLE

HZ000095

TOACTUATOR

BYPASSAND

SLAVEINTERFACE

YS101824

PJ1

GND

OPEN

TB2

FDBK

GND

OPEN

NOT USED FOR THIS APPLICATION

LD1

OPEN

FROM ZONE

CONTROLLER

PJ2

LD2

TB1

T wo Slave W iring Adapters (OE267) consisting of a slave wiring interface card and modular cable are supplied with the OE523 Round Slaved Zone Damper, OE738 Slaved VAV/Zone Rectangular Damper Kit and the OE282-03 Slaved VAV/Zone Damper Kit. These are required when attaching slave actuator(s) to the master zone damper. One slave wiring interface card should be mounted in the control enclosure of the master VAV/Zone controller. It is mounted by fastening the plastic snap-track to the control enclosure with sheet metal screws provided. The other card is mounted in the control enclosure of the slaved zone damper. Fasten it in the control enclosure of the slaved zone damper as was previously done with the master VAV/Zone controller. Run 24 AWG minimum wire between the slave wiring interface cards. Connect modular cables to the slave wiring interface cards and to the zone actuators as shown. See Figure 6 for complete wiring details.

V AV/Zone Controller

Expansion Board Installation & Wiring

T ec hnical Guide

Figure 7: Expansion Board Wiring For Two Position Hot Water Heat Applications

Wiring Considerations

Warning: The 3 relay outputs available on the OE322

Expansion boards are used to supply extra relays and/or analog outputs to control fan and heating functions for the VAV/Zone controller.

When Round VAV/Zone Dampers or Rectangular VAV/Zone Controller Kits are ordered from WattMaster, the OE322 Expansion board is shipped loose for field mounting by others.

Mounting of the OE322 Expansion Board is identical to the previously described mounting for the VAV/Zone controller. Mount the Expansion board near the VAV/Zone controller using the sheet metal screws provided. Be sure the mounting location is close enough so that the supplied modular cable will reach from the VAV/Zone controller to the Expansion board.

The wiring consideration information previously outlined for the VAV / Zone controller should be followed when wiring the OE322 Expansion Boards.

Output Expansion board are each rated for 2 Amps @ 24 VAC. If your device load exceeds these limits, a pilot duty relay (by others) must be used in the circuit.

V AV/Zone Controller

Technical Guide

Expansion Board Installation & Wiring

WattMaster Part #OE322 Relay Expansion Board

w/ Modular Cable

Supplied by WattMaster Mounted by Others

Connect To VAV/Zone Controller Using Modular Cable Supplied By WattMaster

PJ1

WattMaster Part # BK000047 Snaptrack Supplied by WattMaster Mounted by Others. Remove Control Board from Snaptrack & Mount Snaptrack on Box

WattMaster Part #OE322 Relay Expansion Board

w/ Modular Cable

Supplied by WattMaster Mounted by Others

Connect To VAV/Zone Controller Using Modular Cable Supplied By WattMaster

PJ1

WattMaster Part # BK000047 Snaptrack Supplied by WattMaster Mounted by Others. Remove Control Board from Snaptrack & Mount Snaptrack on Box

24VAC

2RAOUT BD.

RLY

R10

RLY

R9R5R2

RLY

R8R4R1

YS101714

REV.3

TB2

COM

TB3

GND

ANALOG

OUTV5

LM358

R11

R12

VR2

7824CT

VR1

Note: 3 Stage Heating is Attained by Sizing All 3

TB1 GND

R14

R13

Heating Elements For Equal KW Output. Each Element Should be Sized for 1/3 of the Total KW Output Required. To Achieve 3 Stage Heating the System would be Configured to Energize

SERIAL #

Contactor C1 for First Stage Heat. For 2nd Stage Heat the System Would be Configured to Deenergize Contactor C1 and Energize Contactor C2 & C3. For 3rd Stage Heat the System Would be Configured to Leave Contactor C2 & C3 Energized and also Energize Contactor C1.

COM

& Wired by Others. Size For Required Contactor(s) Load.

1st Stage Heat Contactor

2nd Stage Heat Contactor

3rd Stage Heat Contactor

24 VAC Contactor(s) Supplied & Installed By Others. 2 Amp Max. Load Each.

Typical Wiring for Single Duct Terminal with Electric Heat

24 VAC Transformer Supplied

24VAC

2RAOUT BD.

RLY

R10

RLY

R9R5R2

RLY

R8R4R1

YS101714

REV.3

TB2

COM

TB3

GND

ANALOG

OUTV5

LM358

R11

R12

VR2

7824CT

VR1

TB1 GND

R14

R13

SERIAL #

COM

Fan Relay

24 VAC Fan Relay Supplied & Installed By Others. 2 Amp Max. Load.

24 VAC Transformer Supplied & Wired by Others. Size For Required Fan Relay Load.

Typical Wiring for Fan Terminal Unit with Cooling Only

2RAOUT BD.

WattMaster Part #OE322 Relay Expansion Board w/ Modular Cable Supplied by WattMaster Mounted & Wired by Others

Connect To VAV/Zone Controller Using Modular Cable Supplied By WattMaster

WattMaster Part # BK000047 Snaptrack Supplied by WattMaster

RLY

R10

RLY

R9R5R2

RLY

R8R4R1

PJ1

YS101714

REV.3

TB2

COM

TB3

GND

ANALOG

OUTV5

LM358

R11

R12

VR2

7824CT

VR1

Note: 3 Stage Heating is Attained by Sizing All 3 Heating Elements For Equal KW Output. Each Element Should be

TB1 GND

Sized for 1/3 of the Total KW Output Required. To Achieve 3

R14

R13

Stage Heating the System would be Configured to Energize Contactor C1 for First Stage Heat. For 2nd Stage Heat the System Would be Configured to De-energize Contactor C1

SERIAL #

and Energize Contactor C2 & C3. For 3rd Stage Heat the System Would be Configured to Leave Contactor C2 & C3 Energized and also Energize Contactor C1.

Mounted by Others. Remove Control Board from Snaptrack & Mount Snaptrack on Box

Figure 8: Expansion Board Wiring For Electric Heat Applications

24VAC

COM

Fan Relay

24 VAC Transformer Supplied & Wired by Others. Size For Required Fan Relay & Contactor(s) Load.

1st Stage Heat Contactor

2nd Stage Heat Contactor

3rd Stage Heat Contactor

Typical Wiring for Fan Terminal Unit with Electric Heat

V AV/Zone Controller

24 VAC Fan Relay & Contactor(s) Supplied & Installed By Others. 2 Amp Max. Load Each.

T ec hnical Guide

Figure 9: Expansion Board Wiring For Modulating Hot Water Heat Applications

Star t-up & Commissioning

General

In order to have a trouble free start-up it is important to follow a few simple procedures. Before applying power for the first time it is very important to correctly address the controller and run through a few simple checks.

Controller Addressing

All VAV/Zone controllers are equipped with address switches. If the VAV/Zone controller is to operate as a Stand Alone controller (not connected to any other HVAC unit or VA V/Zone controllers) the controller address switch should be set for address 1. When the VAV/Zone controller is to be connected to other controllers on a communication loop, each VAV/Zone controllers address switch must be set with a unique address between 1 and 58.

V AV/Zone Controller

When programming the VAV/Zone controller on a Stand Alone or Interconnected System and you are asked to enter the Unit ID, you would enter the address for the controller you wish to program. When programming the VAV/Zone controller on a Networked System and you are asked to enter the Unit ID, you would first enter the MiniLink loop address for the loop the controller is connected to and then enter the VAV/Zone controllers address. See Figure 10 for a diagram depicting address switch settings.

For detailed information regarding communication wiring and connection for Interconnected and Networked systems, please see the Orion System Installation & Troubleshooting Guide.

Technical Guide

Star t-up & Commissioning

Address Switch Shown Is

Set For Address 9

ADD

1 2 4

8 16 32

NET

SW1

ADD

Controller Address Switch

The Address For Each Controller

Must Be Between 1 And 58 And Be

Unique To The Other Controllers

On The Local Loop

ADD

Address Switch Shown Is

Set For Address 13

VAV/Zone Controller Board

R TO

A TU AC

PJ2

SIO

EXPAN

PJ1

ADD

NET

SW1

R SO

SEN E

SPAC

FLO

AIR

R25

GND

AIN

TB2

PJ3

PJ4

Figure 10: Address Switch Setting

Power Wiring

One of the most important checks to make before powering up the system for the first time, is to confirm proper voltage and transformer sizing for the Power/Comm board that is connected to it. Each VAV/ Zone controller requires 6 VA of power delivered to it at 24 VAC. See pages 7 and 8 of this manual for complete wiring and transformer sizing information for the V AV/Zone controller and its associated Power/Comm board. All VAV/Zone controllers must be connected to a Power/Comm board using prefabricated modular cables.

Check all modular connectors to be sure they are completely pushed and locked into their mating connectors. Confirm that all sensors required for your system are mounted in the appropriate location and that the modular cables are plugged into the correct connectors on the VAV/ Zone controller. Check the actuator cable and be sure it is plugged in and secured to the modular connector on the actuator and the VAV/ Zone controller board modular connector . Check that the Modular Room Sensor modular connector is connected to one end of the modular sensor cable and the other end is connected to the modular sensor connector on the VAV/Zone controller board. Be sure any expansion boards connected to the VAV/Zone controller are also correctly wired per the expansion board wiring instructions on pages 7 through 12 of this manual.

After all the above wiring checks are complete, apply power to the Power/Comm board that is connected to the VAV/CAV controller(s).

Initialization

Upon applying power to the VAV/Zone controller the following should occur:

On system power-up, the SCAN LED is extinguished for a few seconds and then the controller “flashes” its address switch setting. If the address switch were set to 7, you would see 7 flashes. After the address is finished, the LED will extinguish for another 5 seconds. At the conclusion of this 5-second delay, the LED will begin a continuous flashing while the Damper Feedback limits are calibrated. If the Damper is driving open, the LED will blink slowly. If the Damper is driving closed, the LED will blink fast. When the calibration is completed, the normal diagnostic flashes will commence. These diagnostic flashes are described later in this document. In addition, during the first few seconds of powerup, all default setpoints are initialized and all outputs are turned off. There is also a 30 second start-up delay to protect the fan and other components from short cycling during intermittent power conditions. If all inputs are operating correctly it will blink once every ten seconds.

V AV/Zone Controller

T ec hnical Guide

Programming The Controller

The next step is programming the controller for your specific requirements. In order to configure and program the VAV/Zone controller you must have a central operators interface or a personal computer with the Prism computer front end software installed. Two different operators interfaces are available for programming of the VAV/Zone controller. You may use either the Modular Service Tool or the Modular System Manager to access the status and setpoints of any VAV/Zone controller or VAV/CAV controller on the system’s communications loop. See the Modular Service Tool and System Manager Programming guide for VAV/Zone controller programming information. If you are going to use a personal computer and the Prism computer front end software, please

see the Orion Prism Computer Front End Operations Manual. No matter which operators interface you use, it is recommended that you proceed with the programming and setup of the controller in the order that follows:

1. Configure The Controller For Your Application

2. Program The Controller Setpoints.

3. Review Controller Status Screens To Verify System Operation And Correct Controller Configuration

Mode

Selection

STATUS

SETPOINTS

SCHEDULES

OVERRIDES

ALARMS

CONFIGURATION

BALANCE - TEST

DOWN

ESC

ENTER

708

DEC

Figure 11: Operators Interfaces

CLEAR

MINUS

708

DEC

System Manager

DOWN

ENTER

CLEAR

ESC

STATUS

SETPOINTS

SCHEDULES

OVERRIDES

ALARMS

V AV/Zone Controller

Technical Guide

Sequence Of Operations

Initialization

V AV/Zone Configuration & Setup

There are a few configuration selections available to the user, which can be used to tailor the software operation to match the mechanical equipment this controller is installed on. These are programmed using either the Modular System Manager, Modular Service Tool or a personal computer with Prism computer front end software installed. See the Operator Interfaces Technical Guide or the Orion Prism Computer Front End Software manual for specific programming information.

General

Several options are available to configure the VAV/Zone controller for the appropriate equipment it is installed on. All of these options can be set from the “Configuration” menu with the exception of “AHU Heat Call” which is set from the “Setpoints” menu. Again, please refer to the Operators Interface T echnical Guide or the Orion Prism Computer Front End Software manual for detailed programming information.

Box Control Method

Set this configuration item for the type of box the VAV/Zone controller is used on. The options available are:

0 = Cooling Only Box (With Reheat if Required) 1 = Heating/Cooling Changeover Box 2 = Series Fan Powered Box With Reheat 3 = Parallel Fan Powered Box With Reheat

Damper Operating Mode

This allows the user to set the direction of rotation the damper moves when driving towards its full open position. The options available are:

0 = Direct Acting (Clockwise To Open Damper) 1 = Reverse Acting (Counterclockwise To Open Damper)

Voting System

If this system is a “Zoned” system as opposed to a true VAV system this option must be set to “Yes”. If it is a true “VAV” system the option should be set to “No”. The options available are:

0 = Yes 1 = No

Voting Zone

If this particular VAV/Zone controller is being used on a “Zoning” system as opposed to a true VAV system, this option must be set to allow the MiniLink Polling Device to determine if this controller should be included in the zoning system voting process. If this is set to “Yes”

this controller will be included in the voting process. If this is a zoning system and it is set to “No” this controller will not vote in the zoning system voting process. If it is a true “VAV” system, the option should be set to “No”. The options available are:

0 = Yes 1 = No

Pressure Independent Boxes - Airflow @ 1” W.C.

If this is a pressure independent box, this option allows you to calibrate the box CFM correctly using the box manufacturers “K” factor. Enter the correct “K” (CFM) factor for the inlet diameter of the box you are configuring.

Expansion Relays - Steps of Reheat

If the box has reheat supplied by an electric coil, this option must be set for the number of electric heating stages on the box. If the box has hot water heat with a 2 position hot water valve, set the number of stages to “1”. For hot water heat with a proportional hot water valve this must be set for “0”. Options available are:

0 = No Staging 1 = 1 Stage of Reheat 2 = 2 Stages of Reheat 3 = 3 Stages of Reheat

Proportional Heating Signal

If the box has hot water reheat using a proportional hot water valve, set this option to match the voltage signal required by the hot water valve you are using. Options available are:

0 = 0-10 VDC Voltage Signal 1 = 2-10 VDC Voltage Signal

Allow Box Heat With AHU Heat

If the box you are using has reheat or auxiliary heat, configuring this setting to 1=Yes will allow the box heat to operate at the same time as the HVAC unit heat. Options available are:

0 = No 1 = Yes

Main Fan Status

If the VAV/Zone controller is installed on a non-fan powered box that has reheat set this option to “Yes” in order to enable box reheat only when the HVAC unit fan is running. A full description of how this setting affects the various box types in the occupied and unoccupied modes is contained under the “Mode Sequence” heading that follows later in this manual. Options available are:

0 = No Heat can operate without fan 1 = Yes Heat cannot operate without fan

Push Button Override Group ID#

During Unoccupied Mode, all V AV/Zone controllers with a corresponding Group ID# will resume Occupied operation whenever any of the VAV/Zone controllers with the same Group ID # has it’s push-button depressed to initiate an override condition. This allows you to group zones in various areas of the building. For example, individual tenants with several offices could restore occupied mode for just their zones and not affect other zones in the building. If you don’t want a specific zone to be a part of any group, enter a ‘0’ for its Group ID #.

V AV/Zone Controller

T ec hnical Guide

Dump Zone

If this VAV/Zone controller is to be used as a “Dump Zone” set this configuration to 1=Yes. The dump zone is a controller without an actuator that is used to control a duct heater or auxiliary heat. Options available are:

0 = No 1 = Yes

AHU Heat Call

This setting is located under the “Setpoints” menu on screen #3. This is used only for the unoccupied mode. For non-fan powered terminal units this temperature setpoint is used to allow auxiliary heat such as baseboard heaters to be energized in an attempt to satisfy the heating demand prior to initiating the HVAC unit Supply Air Heating mode. For fan powered terminal units this setpoint can be used to operate the series or parallel box to satisfy the heating demand by using plenum air and reheat prior to initiating HVAC Supply Air Heating mode.

During unoccupied mode when the temperature in the space drops below the AHU Heat Call setpoint the VA V/Zone controller sends a signal to the VAV/CAV controller to initiate the HVAC unit Supply Air Heating Mode. This setpoint temperature can be set higher or lower than the Space Heating setpoint.

Scheduling

Occupied/Unoccupied Mode

The VAV/Zone Controller monitors the communications loop for its Occupied and Unoccupied mode of operation command. Either the VAV/ CAV Controller or a special Optimal Start Scheduling device can transmit the Occupied command to the VAV/Zone Controller. This requires the VAV/Zone Controllers to all be connected to the system communication loop through their RS-485 connector and to be properly addressed for the command to be received.

Push-button Override Operation

During unoccupied hours, the user can force the VAV/Zone Controller and VAV/CAV Controller back to occupied operation by pressing the override button for a period of time less than 3 seconds. This initiates the override or resets the override timer back to zero during unoccupied hours of operation.

Modes Of Operation

General

There are 7 possible modes of operation for the HVAC Unit and the VAV/Zone controller. These modes are determined by the supply air and/or space demand conditions. They are:

• Supply Air V ent Mode

(Based on HVAC Unit SAT)

• Space Vent Mode

(Based on VAV/Zone Controller Space Temp.)

• Supply Air Cooling Mode

(Based on HVAC Unit SAT)

• Space Cooling Mode

(Based on VAV/Zone Controller Space Temp.)

• Supply Air Heating Mode

(Based on HVAC Unit SAT)

• Space Heating Mode

(Based on VAV/Zone Controller Space Temp.)

• Off Mode (Not displayed. See definition below)

The process of determining each mode is discussed below, but the actual operation of each mode is explained in the section that follows.

Definitions Of Modes

VAV & Zone Control Schemes

On all fan-powered and non-fan-powered terminal units, ‘V AV’ or ‘Zoning’, supply air modes and space demands are calculated the same. If the supply air rises 1 ºF above the cooling setpoint, the supply air mode is heating. To cancel the supply air heating mode, the supply air temperature must fall below the cooling setpoint. If the supply air falls 1 ºF below the heating setpoint, the supply air mode is cooling. To cancel the supply air cooling mode, the supply air temperature must rise above the heating setpoint. If the supply air is between the heating and cooling setpoints, it is considered vent mode.

Supply Air V ent Mode

This mode occurs when the Supply Air Temperature is between the heating and cooling setpoints.

During Override operations, the user can cancel the override by pressing the override button for a period of time between 3 seconds and 10 seconds. This restores the normal unoccupied operation.

On larger installations with several terminal units, the VAV/Zone Controllers can be configured into groups so that an override generated by one VAV/Zone Controller can cause several other controllers to follow along and return to occupied mode for the programmed duration. Other VAV/Zone Controllers not in the same group will simply maintain an unoccupied damper or airflow setting as set by the user.

Push-button overrides are broadcast continuously by the initiating VAV / Zone Controller until the controller itself times out or the override is cancelled by the user. This broadcast forces the air handler to start its main fan and provide cooling or heating, if so configured. It will remain on until the override broadcast has not been detected for at least 2 consecutive minutes.

V AV/Zone Controller

Space Vent Mode

This mode occurs when the Space Temperature is between 0.5 °F below the Cooling Setpoint and 0.5 °F above the Heating Setpoint.

Supply Air Cooling Mode

This mode occurs when the Supply Air Temperature falls to 1.0 °F below the Space Heating Setpoint.

Space Cooling Mode

This mode occurs when the Space Temperature rises to 0.5 °F below the Space Cooling Setpoint.

Supply Air Heating Mode

This mode occurs when the Supply Air Temperature rises to 1.0 °F above the Space Cooling Setpoint.

Space Heating Mode

This mode occurs when the Space Temperature falls to 0.5 °F above the Space Heating Setpoint.

Technical Guide

Sequence Of Operations

Off Mode

During unoccupied mode, the mode is considered ‘OFF’ if the space temperature does not generate a heating mode or cooling mode based on the unoccupied heating & cooling setpoints.

Damper Positions

The actual values for the minimum damper positions that are described in the following paragraphs can be user configured by changing the values in setpoint screens 4, 5 and 6 for the V AV/Zone controller. These minimums are expressed in damper open percentages for pressure dependent terminal units or in CFM for pressure independent terminal units.

Cooling Minimum

When the HVAC unit is in the Supply Air Cooling mode but the space does not require cooling, the VAV/Zone damper will go to the Cooling Minimum position.

Heating Minimum

When the HVAC unit is in the Supply Air Heating mode but the space does not require Heating, the VAV/Zone damper will go to the Heating Minimum position.

Vent Minimum

This is the position the V AV/Zone damper will move to when the HV AC unit is in the Supply Air Vent mode.

Nite/Reheat Minimum

This setpoint has two different functions depending on whether the HVAC unit is in Occupied or Unoccupied mode.

Occupied Mode

If the VAV/Zone controller is used on a non-fan-powered terminal unit that has reheat, the VAV/Zone damper will move to the Nite/Reheat position whenever a Space Heating demand occurs and the HVAC unit is in Supply Air Cooling or Vent modes. When the HVAC unit is in Supply Air Heating mode the VAV/Zone damper will modulate as required to maintain the Space Heating setpoint.

Unoccupied Mode

When using non-fan powered terminal units, the VAV/Zone damper will position itself in the Nite/Reheat minimum position. In order for fan powered terminal units to position the damper to the Nite/Reheat minimum position, the check for main fan status must be selected and the HVAC unit fan must be operating.

Occupied Mode Sequences

Space Vent Mode

This mode only applies to the Occupied Mode of operation. If the equipment is in the Unoccupied Mode, then a lack of heating or cooling demand would generate the Off Mode.

If the HVAC unit is in Supply Air Vent Mode, the user can adjust the damper position on pressure dependent terminal units and the airflow on pressure independent terminal units to provide a fixed amount of ventilation air into the space when there are no heating or cooling de-

mands. During this time, the damper does not modulate on pressure dependent terminal units. On pressure independent terminal units, it only modulates to the extent required to maintain the vent minimum airflow setting.

If the VAV/Zone Controller detects that the HV AC unit is in Supply Air Heating mode, indicating that the air handler has activated its heat, the heating airflow minimum will be substituted for the vent minimum position.

If the VAV/Zone Controller detects that the HV AC unit is in Supply Air Cooling mode, indicating that the air handler has activated its cooling, the cooling airflow minimum will be substituted for the vent minimum position. .

Space Cooling Mode

Occupied Space Cooling mode is initiated by the temperature in the space rising to within 0.5 ºF of the Occupied Cooling Setpoint.

If the HVAC unit is in the Supply Air Heating and another VAV/Zone controller has a cooling demand, the damper/airflow for the VAV/Zone controller requiring cooling will position itself to provide the heating minimum setpoint amount of air into the space. No modulation open will occur because the space does not want the warm air currently being supplied by the air handler.

When the HVAC unit is in the Supply Air Cooling mode, the damper is normally held at the minimum cooling position until the space temperature begins to rise above the cooling setpoint. As the space temperature rises to within 0.5 ºF of the Occupied Cooling Setpoint, the damper/ airflow calculation causes the air valve to open proportionally until the maximum setpoint is achieved at 3.5 ºF above the setpoint. This is a 4 ºF proportional window starting 0.5 ºF below the cooling setpoint to

3.5 ºF above the cooling setpoint.

The damper/airflow is never allowed to modulate outside the user adjusted minimum setpoint and the maximum setpoint. The maximum damper/airflow setpoint applies to heating and cooling modes of operation only . All of the modes have their own individual minimum setting.

Series Flow Fan Terminals

If the VAV/Zone Controller has been configured as a Series Fan Powered terminal unit, the series fan relay will activate and run the series box fan continuously anytime the HVAC unit fan is running.

In all cases, before the series box fan can be activated, the air damper is driven fully closed and held that way for 30 seconds to make sure the series box fan hasn’t inadvertently started to spin backwards. Once the series box fan starts, it waits an additional 10 seconds to allow the fan to spin up before it starts to open the damper and introduce airflow from the HVAC unit fan.

Parallel Flow Fan Terminals

During normal cooling or vent mode and adequate air supply , the parallel fan will be off. During the occupied cooling mode the fan will only activate if the damper/airflow is below a user defined low limit setting. This causes it to be used as a make-up air source. When the damper/ airflow rises 15% above the low limit setpoint, the fan will be deactivated

V AV/Zone Controller

Space Heating Mode

Occupied Space Heating mode is initiated by the temperature in the space falling to within 0.5 ºF of the Occupied Heating Setpoint.

If the HVAC unit is in the Supply Air Cooling mode and another VAV / Zone controller has a heating demand, the damper/airflow for the VAV / Zone controller requiring heating will position itself to provide the Cooling Minimum amount of air into the space. No modulation open will occur because the space does not want the cold air currently being supplied by the air handler.

When the HVAC unit is in the Occupied Supply Air Heating mode, the damper will be held at the Heating Minimum position until the space temperature falls to within 0.5 ºF of the Occupied Heating Setpoint. As the space temperature falls below the heating setpoint, the damper/ airflow calculation causes the air valve to open proportionally until the maximum setpoint is achieved at 3.5 ºF below the setpoint. This is a 4 ºF proportional window starting 0.5 ºF above the heating setpoint to 3.5 ºF below the heating setpoint.

Two different configurations are available for the Occupied Space Heating mode. If the box is configured to allow reheat during Supply Air Heating mode, the reheat relays can be activated even when the HVAC unit is in the Supply Air Heating mode. If the box is configured not to allow reheat when the HVAC unit is in Supply Air Heating mode, the box heat relays will be de-energized when the HVAC unit is in Supply Air Heating mode. In either configuration, when the HVAC unit is in the Supply Air Heating mode, the damper will modulate open proportionally to the space demand. The proportional window for the space temperature is 0.5 ºF above to 3.5 ºF below the heating setpoint. This allows the space to take advantage of the warm supply air in the duct. See Table 3: Relay S taging - Occupied Mode for a complete layout of the various fan and heat relay staging points.

Series Flow Fan Terminals

If the VAV/Zone Controller has been configured as a Series Fan Powered terminal unit, the series fan relay will activate and run the series box fan continuously anytime the HVAC unit fan is running.

T ec hnical Guide

Box Fan Relay & Reheat Relay Staging

Relay s Stag e

On At

+0.5 ºF

Above Box

Heat

Setpoint

At Box Heat

Setpoint

-1.0 ºF

Below Box

Heat

Setpoint

-2.0 ºF

Below Box

Heat

Setpoint

Relay s Stag e

Off At

+1.0 ºF

Above Box

Heat

Setpoint

+1.0 ºF

Above Box

Heat

Setpoint

At Box Heat

Setpoint

-1.0 ºF

Below Box

Heat

Setpoint

Table 3: Relay Staging - Occupied Mode

Occupied Mode

Series

Fan

With

HVAC

Fan

Series

Fan

OFF With

HVAC

Fan

Pa ra llel

Fan

Pa ra llel

Fan

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Parallel Flow Fan Terminals

On parallel fan powered terminal units, the fan will run whenever Space Heating mode is active. At all other times, the fan will only activate if the damper/airflow is below a user defined low limit setting. This causes it to be used as a make-up air source. When the damper/airflow rises 15% above the low limit setpoint, the fan will be deactivated if there are no heating stages active, and no space demand exists.

The check for main fan status setting has no effect on the Parallel Fan box when in the occupied mode. The Parallel Fan will only be energized when in the Space Heating mode.

V AV/Zone Controller

Unoccupied Mode Sequences

Space Vent Mode

This mode only applies to the Occupied Mode of operation. If the equipment is in the Unoccupied Mode, then a lack of heating or cooling demand would generate the Off Mode.

Off Mode

This mode only applies to the Unoccupied Mode of operation. If the equipment is in the Unoccupied Mode, then a lack of heating or cooling demand would generate this mode. The VAV/Zone controller will put the damper into the Night/Reheat minimum position if check main fan status has been selected. If check main fan status has not been selected the damper will be in the fully closed position.

Technical Guide

Sequence Of Operations

Space Cooling Mode

During unoccupied mode the HVAC unit is normally off. Unoccupied Space Cooling mode is initiated by the temperature in the space rising to within 0.5 ºF of the Unoccupied Cooling Setpoint.

If the HVAC unit is in the Unoccupied Supply Air Heating mode because one or more of the VAV/Zone controllers has a heating demand, and another VAV/Zone controller has a cooling demand, the damper/ airflow for the VAV/Zone controller requiring cooling will position itself to provide the heating minimum setpoint amount of air into the space. No modulation open will occur because the space does not want the warm air currently being supplied by the air handler.

When the HVAC unit is in the Unoccupied Supply Air Cooling mode, the damper will be held at the Night/Reheat minimum position until the space temperature begins to rise above the cooling setpoint. As the space temperature rises to within 0.5 ºF of the Unoccupied Cooling Setpoint, the damper/airflow calculation causes the air valve to open proportionally until the maximum setpoint is achieved at 3.5 ºF above the setpoint. This is a 4 ºF proportional window starting 0.5 ºF below the cooling setpoint to 3.5 ºF above the cooling setpoint.

Series Flow Fan Terminals

If the VAV/Zone Controller has been configured as a Series Fan Powered terminal unit and check for main status has been selected, the series fan relay will activate and run the series box fan continuously anytime the HVAC unit fan is running. The damper will be held at the Nite/ Reheat minimum until the space temperature begins to rise above the cooling setpoint. If check for main fan status has not been selected, the series fan relay will activate and run the series box fan when in the Space Cooling mode. The damper will be in the fully closed position until the space temperature begins to rise above the cooling setpoint.

Parallel Flow Fan Terminals

In the Unoccupied Cooling mode the parallel fan will be off whether check for main fan status has been selected or not. If check for main fan status has been selected the damper will be held at the Nite/Reheat minimum until the space temperature begins to rise above the cooling setpoint. If check for main fan status has not been selected the damper will be held in the fully closed position until the space temperature begins to rise above the cooling setpoint.

Space Heating Mode

During unoccupied mode the HVAC unit is normally off. Unoccupied Space Heating mode is initiated by the temperature in the space falling to within 0.5 ºF of the Unoccupied Space Heating Setpoint.

airflow for the VAV/Zone controller requiring heating will position itself to provide the Night/Reheat setpoint amount of air into the space. No modulation open will occur because the space does not want the cold air currently being supplied by the air handler.

When the HVAC unit is in the Unoccupied Supply Air Heating mode, the damper will be held at the Night/Reheat minimum position until the space temperature begins to fall below the Unoccupied Heating Setpoint. As the space temperature falls to 0.5 ºF below the Unoccupied Heating Setpoint, the damper/airflow calculation causes the air valve to open proportionally until the maximum setpoint is achieved at 3.5 ºF below the setpoint. This is a 4 ºF proportional window starting 0.5 ºF above the heating setpoint to 3.5 ºF below the heating setpoint.

As with the Occupied Mode of operation, two different configurations are available for the Unoccupied Space Heating mode. If the box is configured to allow reheat during Supply Air Heating mode, the reheat relays can be activated even when the HVAC unit is in the Supply Air Heating mode. If the box is configured not to allow reheat when the HVAC unit is in Supply Air Heating mode, the box heat relays will be de-energized when the HVAC unit is in Supply Air Heating mode. In either configuration, when the HVAC unit is in the Supply Air Heating mode, the damper will modulate open proportionally to the space demand. The proportional window for the space temperature is 0.5 ºF above to 3.5 ºF below the heating setpoint. This allows the space to take advantage of the warm supply air in the duct.

If check for main fan status is not selected and the VAV/Zone terminal unit has auxiliary heat (baseboard heat etc.) that does not require the HVAC unit fan to operate, reheat can be used without the HVAC unit fan operating. If check for main fan status is selected, the reheat will only operate when the HVAC unit fan is operating.

The VAV/Zone Controller can activate auxiliary heating relays if the relay expansion board has been connected and the correct number of heating stages (1,2 or 3) has been configured. During demands for heat, the first stage will activate whenever the space temperature drops below the heating setpoint. The second stage will activate if the space temperature falls 1.0 ºF below the heating setpoint. The third stage will activate if the space temperature falls 2.0 ºF below the heating setpoint. There is a two-minute delay between staging. This prevents stages from activating at the same time. Once a heating stage has been activated, it must remain on for at least one minute. Once it has been deactivated, it must remain off for at least two minutes. The third stage relay will deactivate when the space temperature rises to within 1.0 ºF of the heating setpoint. The second stage relay will deactivate when the space temperature rises to the heating setpoint. The first stage relay will deactivate when the space temperature rises above the heating setpoint by

1.0 ºF. See Table 4: Relay Staging - Unoccupied Mode for a com- plete layout of the various fan & heat relay staging points.

Series Flow Fan Terminals

If the VAV/Zone Controller has been configured as a Series Fan Powered terminal unit, the series fan will run continuously when the VAV/ Zone controller is in the Space Heating mode no matter whether check for main fan status has been selected or not. If the HVAC unit is in Supply Air Heating mode the damper will modulate to maintain the Space Heating Setpoint.

If the HVAC unit is in the Unoccupied Supply Air Cooling mode because one or more of the VAV/Zone controllers has a cooling demand, and another VAV/Zone controller has a heating demand, the damper/

Any series fan terminal unit that has check for main fan status selected will also operate its series box fan anytime the HVAC unit controller is broadcasting that the HVAC unit fan is operating, regardless of whether

V AV/Zone Controller

T ec hnical Guide

it is calling for heat or not. The damper will be held at the closed position until the main fan status broadcast is received. Once the broadcast is received the damper will then move to its Nite/Reheat minimum position. If check for main fan status has not been selected, the series box fan will only activate and run when it is in Space Heating mode. When in Space Heating mode the damper will move to its Nite/Reheat minimum position. When in Supply Air Heating mode the damper will modulate to maintain the Unoccupied Heating setpoint.

Box Fan Relay & Reheat Relay Staging

Relays Stage

On At

+0.5 ºF

Above Bo x

Heat

Setpoint

At Box Heat

Setpoint

-1.0 º F

Below Box

Heat

Setpoint

-2.0 º F

Below Box

Heat

Setpoint

Relays Stage

Off At

+1.0 ºF

Above Bo x

Heat

Setpoint

+1.0 ºF

Above Bo x

Heat

Setpoint

At Box Heat

Setpoint

-1.0 º F

Below Box

Heat

Setpoint

Notes:

1.) I f check for main fa n stat u s is sel e cted the se ries fan will ac tivate an y ti me th e HVA C unit fa n is op eratin g .

Unoccupied Mode

Series

Fan

See

Note

Series

Fan

See

Note

Pa r a llel

Fan

Pa r a llel

Fan

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Parallel Flow Fan Terminals

If the VAV/Zone Controller has been configured as a Parallel Fan Powered terminal unit, the Parallel fan will run continuously when the VAV / Zone controller is in the Space Heating mode no matter whether check for main fan status has been selected or not. At all other times, the fan will only activate if the damper/airflow is below a user defined low limit setting. This causes it to be used as a make-up air source. When the damper/airflow rises 15% above the low limit setpoint, the fan will be deactivated if there are no heating stages active, and no space demand exists.

If check for main fan status is selected the damper will remain in the closed position until the HVAC unit controller is broadcasting that the HVAC unit fan is operating, regardless of whether it is calling for heat or not. The damper will be held at the closed position until the main fan status broadcast is received. Once the broadcast is received the damper will then move to its Nite/Reheat minimum position. If check for main fan status has not been selected, the damper will stay in the closed position until Space Heating mode is initiated. When in Space Heating mode the damper will move to its Nite/Reheat minimum position. When in Supply Air Heating mode the damper will modulate to maintain the Unoccupied Heating setpoint.

Damper Control

The damper position is calculated by the mode and demand from the space sensor. Included in this calculation is an Integral function. This prevents the damper/airflow from stagnating at a position somewhere above the setpoint because the supply air temperature or duct pressure isn’t quite enough to satisfy the space at the currently calculated proportional position. The Integral causes the calculation to keep adding a small amount of the proportional error back into the damper/airflow position each time a new position is calculated. The amount the Integral adds back in is user adjustable. This value is presented as a number between 0.0 and 10.0. That means that if the integral is less than 1.0, you are adding a percentage, from 0 to 100% of the error back into the calculation. If you increase the Integral above 1.0, you are adding more than 100% back in.

With just proportional control, a 2 ºF error would cause a 50% increase in damper/airflow if the Integral is not included. (2 °F is half of the 4 ºF Proportional Window)

If you had set the Integral to 1.0, the calculation would add 2% to the current damper/airflow calculation each time. The calculation occurs once every 10 seconds, so it would take a little over 4 minutes to reach the programmed 100% maximum.

Example:

1. 50% Remaining / 2% Integral = 25 Moves to get to a 100% Maximum

2. 25 Moves times 10 seconds = 250 seconds or a little over 4 minutes to reach the 100% maximum damper/airflow position.

Table 4: Relay Staging - Unoccupied Mode

V AV/Zone Controller

Of course different space temperature errors and different Integral values cause this calculation to operate slower or faster. It is up to the user to determine the optimum setting that provides the tightest temperature control without causing the damper to continue to hunt or modulate causing premature wear of the actuator gears and motor.

Technical Guide

Sequence Of Operations

The integral also has an effect on the auxiliary heating relays. See the Heating Mode section for a description of this effect.

On pressure dependent terminal units, the damper position is maintained to within ± 3% of the calculated position. No attempt is made to position the damper exactly on the calculated position. This reduces wear and tear on the actuator gears and motors and the amount of airflow involved is not affected by that small amount of damper error.

On pressure independent terminal units, the airflow is maintained to within roughly 3% of the terminal unit size constant but no tighter than 16 CFM on the smallest terminal units. The actual control window is based on the formula:

Window = Terminal unit size X Square Root (1 / 750)

Where Terminal unit size refers to the total rated CFM of the terminal unit.

This sliding window allows the control to be much tighter on the smaller terminal units than can be achieved on the larger terminal units as far as CFM readings. On a large terminal unit, 25 CFM may not be noticeable but on a small terminal unit, 25 CFM may be more than the minimum airflow setting for the space.

If the pressure sensor is disconnected or fails on a pressure independent terminal unit, the controller automatically reverts to pressure dependent operation and generates an alarm to alert the user that a failure has occurred.

On either type of terminal unit, a space sensor failure will force the damper to position itself to the 50% position and it will not change until the sensor is repaired or replaced.

Tenant Override Logs

If you require tenant billing for push-button override usage, a MiniLink Polling Device must be installed on each local loop. The MiniLink Polling Device has the ability to track the amount of override time generated by each space sensor equipped with push-button override.

Storing and retrieving these logs requires a dedicated computer running the Prism front-end software program. No other method exists for retrieving these logs. That means that all of your units will be connected together on the communications loop and the loop will be terminated at a CommLink II device connected to an on-site computer.

Warning: This computer must be on 24 hours a day 7 days a

week running the Prism software in order for tenant logging to be tracked.

The tenant logs are kept on the dedicated job site computer’s hard drive. The only limitation to the number of logs stored is the capacity of the hard drive on the computer they are being logged too.

Note: For proper time and date stamping of the tenant log, you

must configure the air handler to broadcast the time so that the VAV/Zone Controllers can read it and use it in their tenant and trend logs.

Zoning

Description

The Orion system can be configured to operate as a true zoning system with the addition of a MiniLink Polling Device. The MiniLink Polling Device acts as a loop manager receiving information from the VAV/ ZONE controllers, interpreting this information, and then sending a heat, cool or vent signal to the VAV/CAV Controller.

Zone Polling

The MiniLink Polling Device must be configured for zoning operation from the System Manager, Modular Service Tool or Prism Computer front end software. During the setup and programming, the user is required to enter the last VAV/Zone address on the loop. Once configured, the MiniLink Polling Device begins polling each VAV/Zone controller for its temperature and setpoint information. A zone poll cycles through all configured zones in one pass, without interruption.

The following is a list of status information required by the MiniLink Polling Device to correctly perform its HVAC Mode calculations.

• Zone Temperature

• Current Cooling Setpoint

• Current Heating Setpoint

• Current Zone Operating Mode Status & Alarm Conditions

A zone is considered MISSING if it fails to respond to 5 consecutive polling requests. A Missing Zone alarm can be generated in less than 2 minutes. This alarm can generate an alarm callout to maintenance or a supervisor if the system has been properly setup ( See Alarm Reporting Section ).

Zone Voting

If a zone has been configured for the VOTING mode, the MiniLink Polling Device will perform the following tests based on the data received during the zone polling operation. These tests insure that only properly operating zones can have an effect on the HVAC Mode calculation.

• The zone has not been reported as MISSING.

• The zone is not currently undergoing Damper Calibration.

• The Zone Damper has not failed driving Open or Closed,

and it passed Calibration.

• The Zone Temperature readings are between 40 °F and

105 ºF

• The Zone Cooling Setpoint is between 55 °F and 105 ºF

• The Zone Heating Setpoint is between 48 °F and 99 °F

• The Zone has not been declared Maverick by the MiniLink

Polling Device.

• The Zone has been configured as a VOTING zone.

V AV/Zone Controller

T ec hnical Guide

If all the above tests are passed, the zone temperature and setpoints are then included in the HVAC Mode decision, otherwise, this zone is ignored.

Testing for Maverick Zones

During the HVAC Mode decision process, a zone cannot be included in the Voting if it has been declared as Maverick. A zone is determined to be a Maverick if it stays 4 ºF below the Space Heating setpoint for 1 hour or 4 ºF above the Space Cooling setpoint for 1 hour. During this 1 hour time period, the zone is still included in the voting, but it generates a PRIORITY call for heating or cooling to the MiniLink PD. During this 1 hour time period, if the Space Temperature moves to within 2 ºF of its Space Heating or Space Cooling Setpoint, the PRIORITY is canceled. If the zone stays in PRIORITY for greater than 1 hour it then becomes a Maverick zone. At that point its PRIORITY is canceled and the zone is ignored in the voting process, until the Space Temperature changes to within 2 ºF of its Space Heating or Space Cooling Setpoint. If at least 75% of the zones go Maverick simultaneously , the MiniLink Polling Device assumes an abnormal condition has occurred in the building and resets all the zones back to normal. It then restarts the 1 hour Maverick test over again for all zones. Maverick testing can be disabled if your system is connected to a personal computer with the Prism computer front end software installed.

Alarm Detection And Re porting

The VAV/Zone controller continuously performs self diagnostics during normal operations to determine if any operating failures have occurred. These failures can be reported to the user in several ways, depending on the type of system and options installed by the user. If a System Manager or a Modular Service Tool is connected, the alarms will be reported on the Status Screens. If the Prism computer front end software is installed, the alarms will be reported on the main screen of the program and be logged to disk. If the remote communications option is installed, all alarms except the Damper Feedback Failure condition can initiate a callout to a pager to alert someone to the alarm condition. See the computer front end program operations manual for further information on this topic.

The fixed items in the log are listed below:

• Date

• Time

• Space Temperature

• Active Cooling Setpoint

• Active Heating Setpoint

• Supply Air Temperature

• Airflow on Pressure Independent Terminal Units

• Damper Position

Note: For proper time and date stamping of the tenant log,

you must configure VAV/CAV Controller to broadcast the time so that the VAV/Zone controllers can read it and use it in their tenant and trend logs.

Caution: These logs are subject to loss if a power outage

occurs because there is no battery backed memory on the VAV/Zone controllers.

Force Modes or Ov errides

The VAV/Zone controller damper can be forced to one of several positions. These force modes aid the user during troubleshooting or air balancing, etc.

• Force Damper Full Open (Ignores Airflow Reading )

• Force Damper Full Closed (Ignores Airflow Reading )

• Force to Maximum Airflow/Damper Setpoint

• Force to Minimum Airflow/Damper Setpoint

• Force to Fixed Airflow/Damper Setpoint

• Force Damper to Re-Calibrate

Internal Trend Logging

The VAV/Zone controller continuously maintains an Internal Trend Log, which records a fixed set of values at an interval programmed by the user. These values can be retrieved only with the graphical front-end program. In order to utilize these logs, a computer with Prism front end software installed must be connected to the Orion system.

There are 120 log positions available. Once the last (120th) position has been recorded, the log jumps back to the first position and begins overwriting the old data. This means the user is required to retrieve the logs at an interval that is shorter than the duration of the last 120 logs.

Shown below are some log intervals and the duration of 120 logs.

1 Minute Interval .......................... 2 Hour Duration

15 Minute Interval ........................ 30 Hour Duration

30 Minute Interval ........................ 60 Hour Duration

60 Minute Interval ........................ 120 Hour Duration

V AV/Zone Controller

The Force to Fixed Airflow/Damper mode also has a setpoint associated with it. This allows the user to provide a non-changing fixed amount of air into the space that doesn’t affect the Minimum or Maximum setpoints. That means the user doesn’t have to disturb the real minimum and maximum setpoints to achieve a nonstandard setting during their troubleshooting or air balancing modes.

The Force to Minimum mode uses the currently active minimum setting based on the Vent, Cooling or Heating modes. Whatever mode the VAV/Zone controller is in, sets the minimum used by the force mode.

The damper force modes will remain in effect until cancelled by the user, or until the power is removed. Unlike the VAV/CAV Controllers, which require the initiating device to be present at all times during a force mode, the damper force modes are more permanent since they are less likely to damage any equipment. There are no force commands available for the auxiliary relays.

Technical Guide

Troubleshooting

Using LEDs To Verify Operation

The VAV controller is equipped with LEDs that can be used as very powerful troubleshooting tools. The V AV/Zone controller board has three LEDs. Two of these LEDs are used in troubleshooting. See Figure 12 for the LED locations. The LEDs and their uses are as follows:

“REC”

This LED will light up to indicate system communications.

“PWR”

This LED will light up to indicate that 24 VAC power has been applied to the controller.

“SCAN”

This is the diagnostic blink code LED. It will light up and blink out diagnostic codes.

C14

R33

PJ3

TB2

AUX

VR1

R32

SPACE SENSOR

AIN

GND

PWR

RV1

“PWR” LED

R14

R15 R19 R20

R18

R35

R36

R37

C13

R23

CX8

C9 C10 C11

SCAN

REC

R16

HAND HELD

“SCAN” Diagnostics LED

“REC” LED

R10

OUT

“SCAN” LED Operations

As previously described when the board is first powered up the LED will do the following:

• Flashes Once

• Off for 5 seconds

• SCAN LED blinks the board address

(Address 14 = 14 blinks)

• 5 second pause

• 20 second time delay - LED blinks 20 times

• LED blinks slowly as damper moves towards the open

position. The LED blinks fast as the damper moves towards the closed position.

After the above steps the status code is repeatedly blinked every 10 seconds to indicate controller status. The status blink codes are listed in Table 5 below in order of priority.

LED Blinks This

Number Of Times

1 Normal Operation. No Alarm

2 Push-button Override Or

3 Communication Failure 4 Bad Airflow Sensor

5 Bad or M is sin g 6 Damper Failure

7 Damper Feedback Failure

Table 5: SCAN LED Blink Codes

Blink Code

Description

Conditions Exist

Group Override Is A ctive

Space S ensor

Figure 12: LED Locations

“REC” LED Operations

When the controller is communicating this LED will flicker. If it does not flicker check the MiniLink and/or CommLink that is connected to the Power/Comm board which connects to your VAV/Zone controller and make sure the MiniLink and/or CommLink is powered up and properly connected to the Power/Comm board.

“PWR” LED Operations

When the VAV/CA V Controller is powered up the “PWR” LED should light up and stay on continuously. If it does not light up, check to be sure that the modular connector is connected to the board, that the connections are tight and the tab is locked on the connector. Be sure power is connected and turned on to the Power/Comm board and that the modular cable connector is securely connected. If after making all these checks the “PWR” LED does not light up, the board is probably defective.

Only the highest priority failure code will be shown. You must correct the highest priority alarm before other problems will be indicated.

If the “SCAN” LED does not operate as indicated above, first check the address switch setting. See Figure 10 for correct address switch setting procedures. If the address switch setting is correct and the “SCAN” LED still does not behave as indicated above contact Orion Controls Technical support.

Note: Power to the controller being addressed must always

be cycled after changing address switch settings in order for the changes to take effect.

Other Checks

Space Temperature Sensor

If the Space T emperature Sensor is not reading a valid temperature, first make sure that the modular cable connector is firmly plugged into the mating female modular connectors on the board and at the Space T emperature Sensor. Also make sure if a cable coupler is used, that it is firmly connected. If the problem persists, try swapping the sensor with

V AV/Zone Controller

T ec hnical Guide

a known good Space Temperature Sensor. If that sensor works when connected to the VAV/Zone controller board, you can assume you have a defective or damaged sensor.

Supply Air Temperature Sensor

If you suspect the Supply Air Temperature Sensor is not reading correctly , make sure the wiring terminal connections are tight and that any wiring splices are properly connected. You can check the operation of the Supply Air Temperature Sensor by measuring the resistance or voltage using a digital multimeter. Set the meter to DC Volts. Place the positive probe on the AIN terminal and the negative probe on the GND terminal. Read the DC Volts and find that voltage in Table 6 on the following page. Read the temperature corresponding with that voltage and determine if this is close to the actual temperature the sensor is exposed to. If the temperature from the chart is different by more than a few degrees you probably have a defective or damaged sensor. You can also check the sensor resistance to determine correct operation. T o read the resistance set the meter to Ohms. Unplug the sensor connector from the board and measure the resistance across the disconnected wires. This resistance should match the corresponding temperature from Table 6 on the following page.

Airflow Sensor

If the Airflow Sensor seems to be reading incorrectly, first check the Airflow Sensor’s modular cable connector and be sure it is firmly connected to its mating connector on the VAV/Zone controller board. Also make sure that jumper JP2 on the VAV/Zone controller board is set properly for the type of system you are using. See Figure 3 for the jumper location. If this is a Zoning system, the jumper must be removed. If it is a true VAV system, the jumper needs to be in place. Y ou will have problems setting and measuring proper airflows if this jumper is not set according to your system type.

Caution: If the JP2 Jumper on the VAV/Zone controller is

not set correctly your CFM readings will not be accurate.

Check the Airflow Sensor tubing connections at the airflow pickup tubes. The high pressure port of the sensor needs to be connected to the upstream pickup tube. The low pressure port of the sensor needs to be connected to the downstream pickup tube.

If none of the above procedures solves the problem, remove power from the VAV/Zone controller. Shut down the HVAC unit supplying the duct that the VAV/Zone damper is located on. Be sure that no airflow is present in the duct. Reapply power to the board and wait for the VAV/ Zone controller to run through its calibration sequence. Restart the HVAC unit and check the VAV/Zone controller CFM readings. If the CFM reading still seems to be in error, you probably have a defective Airflow Sensor and will need to replace it.

Actuator

Check the Modular cable between the controller and the actuator. Be sure both ends of the cable are firmly connected to the mating connectors on the actuator and the VAV/Zone controller board. Be sure the damper moves freely and is not bound. Do this by pressing the actuator clutch button and rotating the damper shaft in both directions to verify smooth operation. If binding is present fix the problem as required. Remove power from the VAV/Zone controller. Reapply power and observe the damper rotation. If the actuator does not drive the damper in both directions, the actuator is probably defective or damaged. Another test that can be performed, is to swap cables with another known operating actuator to determine if the cable could be bad. If the problem goes away you have a defective cable that must be replaced. You can also try swapping a functioning actuator with the suspected defective actuator. If this solves the problem then the defective actuator will need to be replaced.

Expansion Board

If the Expansion Board does not seem to operate correctly, first make sure the modular cable between the Expansion Board and the VAV/ Zone controller is firmly connected at both ends. Be sure that the Expansion Board has been configured correctly. The expansion board must be configured using the Modular Service Tool, Modular System Manager or Prism computer front end software, for your application, before it will operate. You must configure it for the number of heat stages and if this is a fan terminal, whether it is a Series or Parallel Flow fan terminal. On a non fan terminal unit, when a call for heat is initiated the LED labeled RLY2 should light up. If the expansion board is configured as a fan terminal, on a call for the fan, the LED labeled RLY1 should light up. If the LEDs do not light up the Expansion Board is probably defective and must be replaced.

V AV/Zone Controller

Technical Guide

Troubleshooting

Temperature – Resi stance – Voltage For Type III 10 K Ohm Thermistor Sensors

Temp

(ºF)

-10 93333 4.620 60 14681 3.042 86 8153 2.297

-5 80531 4.550 62 14014 2.985 88 7805 2.242 0 69822 4.474 64 13382 2.927 90 7472 2.187 5 60552 4.390 66 12758 2.867 95 6716 2.055

10 52500 4.297 68 12191 2.810 100 6047 1.927 15 45902 4.200 69 11906 2.780 105 5453 1.805 20 40147 4.095 70 11652 2.752 110 4923 1.687 25 35165 3.982 71 11379 2.722 115 4449 1.575 30 30805 3.862 72 11136 2.695 120 4030 1.469 35 27140 3.737 73 10878 2.665 125 3656 1.369 40 23874 3.605 74 10625 2.635 130 3317 1.274 45 21094 3.470 75 10398 2.607 135 3015 1.185 50 18655 3.330 76 10158 2.577 140 2743 1.101 52 17799 3.275 78 9711 2.520 145 2502 1.024 54 16956 3.217 80 9302 2.465 150 2288 0.952 56 16164 3.160 82 8893 2.407 58 15385 3.100 84 8514 2.352

Resistance

(Ohms)

Voltage @

Input (VDC)

Temp

(ºF)

Resistance

(Ohms)

Voltage @

Input (VDC)

Temp

(ºF)

Resistance

(Ohms)

Voltage @

Input (VDC)

Ther mistor Sensor Testing Instructions

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 set on DC volts. Place the “-” (minus) lead on GND terminal 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.

Table 6: Temperature Sensor - Voltage & Resistance for Type III Sensors

V AV/Zone Controller