WattMaster VAVBOX User Manual

www.wattmaster.com

VAVBOX Contr oller

Technical Guide

Table Of Contents

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

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

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

General ....................................................................................................................................................................................... 5

VAVBOX Controller Analog Inputs:............................................................................................................................................. 5

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

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

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

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

General ....................................................................................................................................................................................... 7

Controller Mounting .................................................................................................................................................................... 7

Transformer Sizing & Wiring ....................................................................................................................................................... 7

Expansion Board Installation & Wiring .......................................................................................................... 8

Wiring Considerations ................................................................................................................................................................ 8

Start-up & Commissioning ............................................................................................................................10

General ..................................................................................................................................................................................... 10

Controller Addressing ............................................................................................................................................................... 10

Power Wiring .............................................................................................................................................................................11

Initialization ................................................................................................................................................................................11

Programming The Controller .................................................................................................................................................... 12

Sequence Of Operations ............................................................................................................................... 13

Initialization ............................................................................................................................................................................... 13

VAVBOX Configuration & Setup............................................................................................................................................... 13

Scheduling ................................................................................................................................................................................ 14

Modes Of Operation ................................................................................................................................................................. 14

Damper Positions ..................................................................................................................................................................... 15

Occupied Mode Sequences ..................................................................................................................................................... 15

Unoccupied Mode Sequences .................................................................................................................................................. 16

Damper Control ........................................................................................................................................................................ 18

Tenant Override Logs ............................................................................................................................................................... 19

Alarm Detection And Reporting ................................................................................................................................................ 19

Internal Trend Logging.............................................................................................................................................................. 19

Force Modes or Overrides ........................................................................................................................................................ 20

Troubleshooting ............................................................................................................................................ 21

Using LED’s To Verify Operation .............................................................................................................................................. 21

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.wattmaster.com Form: WM-VAVBOX-TGD-01C Copyright 2006 WattMaster Controls, Inc. WattMaster Controls, Inc. assumes no responsibility for errors, or omissions. This document is subject to change without notice.

Controller Over view

Technical Guide

Features

VAVBOX Controller

This manual applies to the VAVBOX controller that is included in the following W attMaster products:

MG742-VAV Pressure Dependent VAVBOX Kit For

Terminal Units w/oFan Electric or Hot Water Heat

MG744-VAV Pressure Independent VAVBOX Kit For

Terminal Units w/oFan Electric or Hot Water Heat

MG742-03-VAV Pressure Dependent VAVBOX Kit For

Terminal Units or Fan Terminal Units With Electric or Hot Water Heat

MG744-03-VAV Pressure Independent VAVBOX Kit For

Terminal Units or Fan Terminal Units With Electric or Hot Water Heat

The VAVBOX Controller is used for controlling airflow and operation of VAV 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 which monitors space temperature allowing the VAVBOX controller to modulate a damper in response to space temperature, duct temperature and airflow requirements in the controlled space.

The VAVBOX 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 VAVBOX controller with feedback monitoring for precise positioning of the actuator.

OE322 Output Expansion Board

The OE322, 3 Relay with Analog Output Expansion board is used in conjunction with the VAVBOX Controller board to allow for control of VAV terminal units, including series and parallel fan terminal units with up to 2 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 VAVBOX 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 VAC or 24 VDC. The analog output provides a 0 – 10 VDC modulating signal output into a 1K ohm minimum load.

The VAVBOX controller has three integral modular jacks for connection to the actuator, airflow sensor (for pressure independent applications), and relay or analog expansion boards, via modular cables. The controller has an on-board dip switch provided for board addressing.

562 REV 3

YS101

R35

R26

LD3

POWER

R21

SCAN

LD2

REC

R12 R11

R10

TOKEN

NET

LD1

R14

R13

R100

PJ2

ACTUATOR

4.00”

GND

24VAC

R17

R16

Q3Q2

7824

R15

VR1

D1 K1

7.00"

AUX2

AUX1

AUX

+VS

GND

TMP

T'S TAT

COMM

CX10

75176

U10

SW1

ADDRESS

ADD

CX6

PJ1

EXPANSION

R28

R25

C15

U11

R24

C11

R20

EWDOG

R19

CX5

C2C1

GND

R32

ADJ

C14

VREF

R23

P.U.

R22

C10

RAM

EPROM

CX2

FLOW

R27

C13

CX9

16L8

RN1

CX8

R34

R18

CX4

CX3

CX1

PAL

Figure 1: V AVBOX Controller Dimensions

V A VBO X Controller 3

Technical Guide

Controller Over view

Figure 2: OE322 Output Expansion Boards

Air Flow Sensor Modular Connector

Auxiliary Wiring Terminals

Room Sensor Wiring Terminals

Address Switch (SetBetween1&58)

Communication

Wiring

Terminals

Communications Driver Chip

Power LED

24 VAC Power Terminals

Typical Pin 1 Indicator

FLOW

AUX +VS

AUX1

AUX2

GND

R32

T'S TAT

TMP

GND

SHLD

YS101

R35

562 REV 3

24VAC

GND

RAM Chip

R34

CX8

RN1

R27

CX9

C13

C14

R22

ADJ

VREF

P.U.

R23

R28

R24

U11

R19

C11

R20

C15

EWDOG

R25

COMM

R26

CX10

75176

ADDRESS

SW1

U10

LD3

POWER

R21

VR1

7824

EPROM Chip

R18

CX4

RAM

C10

ADD

2 4 8

16 32 TOKEN NET

R14

LD2

LD1

REC

SCAN

R16

R17

80C55 2

EPROM

CX6

R100

R13

R10

R12C6R11

R15

PAL Chip

CX3

CX1

PAL

16L8

R1 R2 R3

CX2

CX5

PJ1

PJ2

C2C1

R5 R6 R7

EXPANSION

ACTUATOR

Damper Actuator Positioning Relay “Open”

Damper Actuator Positioning Relay “Close”

Snap Track For Controller Mounting

Expansion Board Modular Connector

Damper Actuator Modular Connector

Figure 3: V AVBOX Controller Component Locations

“REC” LED

“SCAN” LED

V A VBO X Controller

Controller Inputs and Outputs

Technical Guide

General

The following inputs and outputs are available on the VAVBOX 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 VAVBOX Controller see Figure 3. For wiring of inputs and outputs see Figure 4 thru 9.

V AVBOX Controller Analog Inputs:

Input #1: Space Temperature Sensor

The Room Sensor that reads space temperature is attached the TMP and GND terminals. If the Room Sensor with slide adjust option is used a third wire connects to terminal AUX1.

Input #2: Airflow Sensor

If the VA VBOX 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 VAVBOX 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.

Input #3: Supply Air Temperature Sensor

The optional Supply Air Temperature Sensor is connected to terminals AUX2 and GND when it is used. If it is to be used as a Supply Air Sensor , it should be mounted in the supply duct close to the terminal unit where the VA VBOX controller is installed. This sensor can be used for monitoring purposes or in place of the Supply Air T emperature Broadcast from the WMVAV Controller.

Note: All temperature sensors must be Thermistor Type III.

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 1 for relay sequencing information.

Stag e 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 1: Relay Sequencing For 3 Stage Heating

Other Controller Connections

Expansion Board Modular Connector

This modular connector is used to connect the optional OE322 Output Expansion Board to the VAVBOX 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 VAVBOX controller to a tri-state actuator.

V A VBO X Controller

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.

Technical Guide

Controller Inputs and Outputs

Airflow Probe & Sensor

(For Pressure Independent Applications Only)

Airflow

Duct Supply Or Discharge Temperature Sensor

(See Note 2)

Connection To AUX Terminal Is Only Required When Sensor Is Specified

With Slide Adjust Option

Connect To Next VAVBOX

Controller Or WMVAV

Controller On Local

Communications Loop

Line Voltage

Locate In Supply Or

Discharge Duct

Near Zone Damper

Room Sensor

A R M E R C O O

OVR

L E R

TMP

GND

AUX

Notes:

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

2.) A Duct SupplyAir Temperature Sensor is not required when the VAVBOX Controller is connected to an WMVAV Unit Controller board. A global Supply Air temperature is broadcast by the WMVAV Unit Controller. The Supply Air Temperature Sensor is required if the VAVBOX Controller is required to operate as a “Stand Alone” controller. The Duct Sensor can also be placed on the discharge side of the VAVBOX duct and used as a Discharge Temperature Sensor to monitor VAVBOX discharge air temperature if desired. This is normally used only if the VAV Terminal unit has heating capabilties.

Zone Actuator

R34

R18

CX4

CX3

CX8

RN1

R27

CX9

C13

RAM

C14

ADJ

VREF

R28

U11

C15

R25

CX10

COMM

R26

80C55

R22

P.U.

C10

R23

R24

R19

C11

R20

EWDOG

ADDRESS

ADD

75176

SW1

U10

8 16 32

LD3

POWER

TOKEN NET

R14

LD2

LD1

R21

REC

SCAN

VR1

7824

R16

R17

CX1

PAL

16L8

R1 R2

EPROM

CX2

CX5

R5 R6 R7

PJ1

EXPANSION

CX6

R100

PJ2

R13

R12C6R11

R10

R15

ACTUATOR

To Optional Relay Expansion Board

SHLD

24VAC GND

AUX1

AUX2

GND

TMP

GND

FLOW

AUX +VS

AUX1

AUX2

GND

R32

T'STAT

TMP

GND

YS101

R35

562REV 3

24VAC

GND

24 VAC Transformer

Size For 6 VA

Maximum Load

Figure 4: V AVBOX Controller Wiring

Controller Installation & Wiring

General

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

Controller Mounting

If the Round Zone Dampers were purchased from W attMaster , the controller and actuator are factory mounted and wired in the damper control enclosure. If your VAVBOX 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 WattMaster controls in their terminal units for an additional charge. An installation worksheet and instructions are available for the WattMaster VAVBOX controller package which can be shipped with the VAVBOX control(s) to the terminal unit manufacturer to simplify third party factory mounting and wiring of the controller.

When the VAVBOX 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 VAVBOX 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 WMVAV controller. See Figure 4 for VAVBOX controller wiring diagram.

1. Size and wire the transformer per the instructions. Failure to size the transformer and/or wire the transformer correctly may cause the VAVBOX controllers to not operate erratically or not at all. See Figure 5 for wiring

and transformer sizing information.

2. If a Duct 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 A VBO X Controller

Technical Guide

Some installers like to use one large 24VAC transformer to power several devices. This is allowable as long as polarity is maintained to each device on the transformer circuit.

using a separate transformer for each device in order to eliminate the potential for damaging controllers due to incorrect polarity.

separate transformers also allows redundancy in case of a transformer failure. Instead of having 8 controllers inoperative because of a malfunctioning transformer you have only 1 controller off line. If the installer does decide to use a large transformer to supply power to several devices, the following transformer and wire sizing information is presented to help the installer correctly supply 24VAC power to the devices.

Following is a typical example to help the installer to correctly evaluate transformer and wiring designs.

Each VAVBOX Controller requires 6 VA @ 24VAC power. In the examples below we have a total of 10 VAV Controllers.

10 VAVBOX Controllers @ 6VA each................ 10 x 6VA =60VA.

The above calculation determines that our transformer will need to be sized for a minimum of 60VA if we are to use one transformer to power all the controllers. We will use a 75 VA transformer, as this is a readily available size that meets our VA load requirements.

Next we must determine the maximum length of run allowable for the wire gauge we wish to use in the installation. Each wire gauge below has a voltage drop per foot value we use to calculate total voltage drop.

18ga wire.................................0.00054 = voltage drop per 1’ length of wire

16ga wire.................................0.00034 = voltage drop per 1’ length of wire

14ga wire.................................0.00021 = voltage drop per 1’ length of wire

For our example we will use 18 gauge wire. WattMaster recommends 18 gauge as a minimum wire size for all power wiring.

Next use the voltage drop per foot value for 18 gauge wire from the list above and multiply by the total VA load of the 10 controllers to be installed.

0.00054 (Voltage drop per foot for 18 gauge wire) x 60VA controller load = Volts/Ft.

WattMaster VAVBOX controllers will operate efficiently with a voltage drop no greater than 2 Volts. Divide the total allowable voltage drop of 2 Volts by the number you arrived at above and you have the maximum number of feet you can run the 18 gauge wire with an 75 VA transformer with no more thana2Voltdropatthefarthest controller from the transformer..

Parallel circuiting of the wiring instead of wiring all 10 controllers in series allows for longer wire runs to be used with the same size wire (as shown in our examples below). transformer size, multiple transformers, circuiting, etc., when laying out an installation. No matter what layout scheme is decided upon, it is mandatory that the farthest controller on the circuit is supplied with a minimum of 22 Volts and that the polarity is maintained to all controllers connected to the transformer.

Warning:

It is often necessary for the installer to calculate and weigh the cost and installation advantages and disadvantages of wire size,

If polarity is not maintained, severe damage to the devices may result. WattMaster Controls recommends

0.0324

2 (Volts total allowable voltage drop)

0.0324 (Voltage drop per 1 ft. @ 60VA load)

= 61.73

feet

Using

24VAC Power - Transformer & Wire Sizing Considerations For VAVBOX Controllers

120 / 24VAC

Distance A to B cannot exceed 61.73 Ft.

Distance from A to B cannot exceed 123.46 Ft. Distance from A to C cannot exceed 123.46 Ft.

Figure 5: WMVAV Controller Transformer Sizing

Transformer Sizing & Wiring

Each VAVBOX controller requires 6 VA minimum at 24 VAC in order to function properly. Wiring and transformer information shown above is provided to help correctly size and layout wiring schemes for the VAVBOX controllers. As stated above, all wiring should be 18 Ga. minimum. Long runs may require heavier gauge wire to keep the voltage drop within the 2 volt maximum range. Please follow these guidelines.

V A VBO X Controller

120 / 24VAC

Distance from A to B cannot exceed 230.40 Ft. Distance from A to C cannot exceed 308.64 Ft. Distance from A to D cannot exceed 308.64 Ft. Distance from A to E cannot exceed 308.64 Ft. Distance from A to F cannot exceed 308.64 Ft.

Warning: If polarity between controllers is not maintained,

severe damage to the controllers may result. W attMaster recommends using a separate transformer for each controller in order to eliminate the potential for damaging controllers due to incorrect polarity.

Technical Guide

Expansion Board Installation & Wiring

Figure 6: 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 VAVBOX controller.

When Round VAVBOX Dampers or Rectangular VAVBOX Controller Kits are ordered from W attMaster, 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 VAVBOX controller. Mount the Expansion board near the VAVBOX 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 VAVBOX controller to the Expansion board.

The wiring consideration information previously outlined for the VAVBOX 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 A VBO X Controller

Expansion Board Installation & Wiring

Technical Guide

WattMaster Part #OE322 Relay Expansion Board

w/ Modular Cable

Supplied by WattMaster Mounted by Others

Connect To VAVBOX 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 VAVBOX 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 VAVBOX 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 7: Expansion Board Wiring For Electric Heat Applications

V A VBO X Controller

24VAC

COM

Fan Relay

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

24 VAC Fan Relay &

1st Stage Heat Contactor

2nd Stage Heat Contactor

3rd Stage Heat Contactor

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

Typical Wiring for Fan Terminal Unit with Electric Heat

Technical Guide

Figure 8: 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 VAVBOX controllers are equipped with address switches. If the VAVBOX controller is to operate as a Stand Alone controller (not connected to any other HVAC unit or VAVBOX controllers) the controller address switch should be set for address 1. When the VAVBOX con-

troller is to be connected to other controllers on a communication loop, each VAVBOX controllers address switch must be set with a unique address between 1 and 58.

When programming the VA VBOX controller and 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 VAVBOX controllers address. See Figure 10 for a diagram depicting address switch settings.

V A VBO X Controller

Star t-up & Commissioning

Technical Guide

TOKEN

NET

Address Switch Shown Is

Set For Address 9

ADD

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

1 2 4

TOKEN NET

NET

Address Switch Shown Is

Set For Address 13

TOKEN

VAVBOX Controller Board

R34

FLOW

RN1

AUX

R27

+VS

AUX1

AUX2

ADD

GND

TMP

GND

SHLD

YS101

562 REV 3

C13

ADJ

R32

T'STAT

R28

C15

R25

COMM

R26

R35

24VAC

GND

R18

C10

R19

ADDRESS

SCAN

R16

R17

CX4

RAM

80C55 2

ADD

2 4 8

16 32 TOKEN NET

R14

LD2

LD1

REC

CX8

CX9

C14

R22

VREF

P.U .

R23

R24

U11

C11

R20

EWDOG

CX10

75176

SW1

U10

LD3

POWER

R21

VR1

7824

CX3

CX1

EPROM

CX5

CX6

R100

R13

R10

R12C6R11

R15

PAL

16L8

R1 R2 R3

CX2

C2C1

R5 R6 R7

PJ1

PJ2

EXPANSION

ACTUATOR

Figure 9: Address Switch Setting

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

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 VAVBOX boards that are connected to it. Each V AVBOX controller requires 6 VA of power delivered to it at 24 VAC. See page 7 of this manual for complete wiring and transformer sizing information for the VAVBOX controller.

Check all connections to be sure they are tight with no loose wire starnds hanging loose. Confirm that all sensors required for your system are mounted in the appropriate location and wired correctly to the VA VBOX controller. Check the actuator cable and be sure it is plugged in and secured to the modular connector on the actuator and the VAVBOX controller board modular connector. Be sure any expansion boards connected to the VAVBOX controller are also correctly wired per the expansion board wiring instructions on pages 8 through 102 of this manual.

After all the above wiring checks are complete, apply power to the first VAVBOX on the loop, that is connected to the WMVAV controller.

Initialization

Upon applying power to the VAVBOX 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. 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 A VBO X Controller

Technical Guide

Programming The Controller

The next step is programming the controller for your specific requirements. In order to configure and program the VAVBOX 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 VAVBOX controller. You may use either the Modular Service Tool or the Modular System Manager to access the status and setpoints of any VA VBOX controller or WMVAV controller on the systems communications loop. See the Operators Interface T echnical Guide for VAVBOX controller programming information. If you are going to use a personal computer and the

Prism computer front end software, please see the WattMaster 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 10: Operators Interfaces

CLEAR

MINUS

708

DEC

System Manager

DOWN

ENTER

CLEAR

ESC

STATUS

SETPOINTS

SCHEDULES

OVERRIDES

ALARMS

V A VBO X Controller

Sequence Of Operations

Technical Guide

Initialization

V AVBOX 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 Prism Computer Front End Software manual for specific programming information.

General

Several options are available to configure the VAVBOX 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 Technical Guide or the Prism Computer Front End Software manual for detailed programming information.

Box Control Method

Set this configuration item for the type of box the VAVBOX 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)

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.

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 Hea t With AHU Heat

If the box you are using has reheat, 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 VAVBOX 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 VA VBOX controllers with a corresponding Group ID# will resume Occupied operation whenever any of the VAVBOX 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 #.

Dump Zone

If this VAVBOX 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

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”.

V A VBO X Controller

AHU Heat Call

This setting is located under the “Setpoints” menu on screen #3. This is used only for the unoccupied mode. 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.

Technical Guide

Sequence Of Operations

During unoccupied mode when the temperature in the space drops below the AHU Heat Call setpoint the VA VBOX controller sends a signal to the WMVA V 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 VAVBOX Controller monitors the communications loop for its Occupied and Unoccupied mode of operation command. Either the WMVAV Controller or a special Optimal Start Scheduling device can transmit the Occupied command to the VAVBOX Controller. This requires the VAVBOX 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 VAVBOX Controller and WMVAV 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.

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 VAVBOX Controllers can be configured into groups so that an override generated by one VAVBOX Controller can cause several other controllers to follow along and return to occupied mode for the programmed duration. Other VAVBOX 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 VA VBOX 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.

Modes Of Operation

General

There are 7 possible modes of operation for the HVAC Unit and the VAVBOX 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 VAVBOX Controller Space Temp.)

• Supply Air Cooling Mode

(Based on HVAC Unit SAT)

• Space Cooling Mode

(Based on VAVBOX Controller Space Temp.)

• Supply Air Heating Mode

(Based on HVAC Unit SAT)

• Space Heating Mode

(Based on VAVBOX 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

VAVBOX Control Schemes

On all fan-powered and non-fan-powered terminal units, 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. T o 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.

Space Vent Mode

This mode occurs when the Space T emperature 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.

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.

V A VBO X Controller

Technical Guide

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 5, 6 and 7 for the VA VBOX 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 VAVBOX 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 VAVBOX damper will go to the Heating Minimum position.

Vent Minimum

This is the position the VA VBOX damper will move to when the HVAC 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 VAVBOX controller is used on a non-fan-powered terminal unit that has reheat, the VAVBOX 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 VAVBOX damper will modulate as required to maintain the Space Heating setpoint.

Unoccupied Mode

When using non-fan powered terminal units, the VA VBOX 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 demands. 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 VAVBOX 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 VAVBOX 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 VAVBOX controller has a cooling demand, the damper/airflow for the VAVBOX 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 VAVBOX 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 A VBO X Controller

Technical Guide

Sequence Of Operations

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 VAVBOX controller has a heating demand, the damper/airflow for the VA VBOX 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 2: Relay Staging - Occupied Mode for a complete layout of the various fan and heat relay staging points.

Series Flow Fan Terminals

If the VAVBOX 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.

Box Fan R elay & Reh eat Relay Staging

Relays Stage

On At

+0 .5 º F

Above Box

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 º F

Above Box

Heat

Setpoint

+1 .0 º F

Above Box

Heat

Setpoint

At Box Heat

Setpoint

-1.0 º F

Below Box

Heat

Setpoint

Occupied Mode

Series

Fan

With

HVAC

Fan

Series

Fan

OFF With

HVAC

Fan

Pa r a lle l

Fan

Pa r a lle l

Fan

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Table 2: Relay Staging - Occupied Mode

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.

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 VAVBOX 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.

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.

V A VBO X Controller

Technical Guide

If the HVAC unit is in the Unoccupied Supply Air Heating mode because one or more of the VAVBOX controllers has a heating demand, and another VAVBOX controller has a cooling demand, the damper/ airflow for the VAVBOX 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 VAVBOX 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.

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 VAVBOX 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 VAVBOX 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 3: Relay Staging - Unoccupied Mode for a com- plete layout of the various fan & heat relay staging points.

Series Flow Fan Terminals

If the VAVBOX Controller has been configured as a Series Fan Powered terminal unit, the series fan will run continuously when the VAVBOX 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 VAVBOX controllers has a cooling demand, and another VAVBOX controller has a heating demand, the damper/ airflow for the VAVBOX 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.

V A VBO X Controller

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 HV AC 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

Technical Guide

Sequence Of Operations

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

Rela y s S ta g e

On At

+0.5 º F

Above Box

Heat

Setpoint

At Box Heat

Setpoint

-1.0 ºF

Below Box

Heat

Setpoint

-2.0 ºF

Below Box

Heat

Setpoint

Rela y s S ta g e

Off At

+1.0 º F

Above Box

Heat

Setpoint

+1.0 º F

Above Box

Heat

Setpoint

At Box Heat

Setpoint

-1.0 ºF

Below Box

Heat

Setpoint

Notes:

1.) If che c k fo r main fan s ta tu s is s e lec te d th e s e rie s fa n w ill a c tiv a te anytime the HVAC unit fan is operating.

Unoccupied Mode

Series

Fan

See

Note

Series

Fan

See

Note

Para lle l

Fan

Para lle l

Fan

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Heat

Stage

Parallel Flow Fan Terminals

If the VAVBOX Controller has been configured as a Parallel Fan Powered terminal unit, the Parallel fan will run continuously when the VAVBOX 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.

Table 3: Relay Staging - Unoccupied Mode

V A VBO X Controller

Technical Guide

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.

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.

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.

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 VAVBOX Controllers can read it and use it in their tenant and trend logs.

Alarm Detection And Reporting

The VAVBOX 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.

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.

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Internal Trend Logging

The VA VBOX controller continuously maintains an Internal T rend 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 system.

Technical Guide

Sequence Of Operations

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

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 WMV AV Controller to broadcast the time so that the VA VBOX 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 VAVBOX controllers.

Force Modes or Overrides

The VAVBOX 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

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 VAVBOX 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 WMVAV 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.

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Troubleshooting

Technical Guide

Using LED’s To Verify Operation

The VAVBOX controller is equipped with LEDs that can be used as very powerful troubleshooting tools. The VAVBOX 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.

“SCAN” Diagnostics LED

“REC” LED

R17

R16

Q3Q2

7824

R15

R26

VR1

D1 K1

R21

SCAN

LD2

REC

LD1

R14

R12 R11

R10

R13

NET

PJ2

R100

LD3

POWER

TOKEN

“PWR” LED

CX10

75176

U10

SW1

ADDRESS

ADD

CX6

PJ1

nections 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.

“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 the following table 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 Missing

6 Damper Failure 7 Damper Feedback Failure

Blink Code

Description

Conditions Exist

Group Override Is Active

Space Sensor

ACTUATOR

EXPANSION

Figure 11: 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 VAVBOX 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 WMVAV 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 con-

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Table 4: SCAN LED Blink Codes

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 WattMaster 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.

Technical Guide

Troubleshooting

Other Checks

Space Temperature Sensor

If the Space T emperature Sensor is not reading a valid temperature, first make sure that the Space Temperature Sensor is correctly wired and that the terminal connections are all tight. If the problem persists, try swapping the sensor with a known good Space Temperature Sensor. If that sensor works when connected to the VAVBOX controller board, you can assume you have a defective or damaged sensor.

Duct Air Temperature Sensor

If you suspect the Duct 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 Duct 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 5 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. To 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 5 on the fol- lowing 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 VAVBOX controller board.

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.

in the duct. Reapply power to the board and wait for the VAVBOX controller to run through it’s calibration sequence. Restart the HVAC unit and check the V AVBOX 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 VAVBOX 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 VAVBOX 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 VA VBOX 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.

If none of the above procedures solves the problem, remove power from the VAVBOX controller. Shut down the HVAC unit supplying the duct that the V AVBOX damper is located on. Be sure that no airflow is present

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Technical Guide

Temperature – Resistance – 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 5: Temperature Sensor - Voltage & Resistance for Type III Sensors

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WattMaster Controls Inc.·8500 NW River Park Drive·Parkville MO·64152

Phone (816) 505-1100 E-mail: mail@wattmaster.com Fax (816) 505-1101

WattMaster VAVBOX User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual