Vykon VT76X7, VT7657B5x28(X), VT7607B5x28(X) User Manual

PIR Ready VT76X7 Series

Programmable & Non-Programmable Thermostats

With Humidification & Dehumidification Strategy

For Commercial HVAC Applications

September 1, 2010

Product overview

The VT76x7 PI thermostat family is specifically designed for single stage
and multi-stage control of heating/cooling equipment such as rooftop and
self-contained units with humidifier and/or dehumidifier. The product
features an embedded complete humidity solution with an intuitive, menu­driven, backlit LCD display that walks users through the programming
steps, making the process extremely simple. Accurate temperature &
relative humidity control is achieved due to the product’s PI time
proportional control algorithm, which virtually eliminates temperature offset
associated with traditional, differential-based thermostats.

All models contain one digital input, which can be set by the user to
monitor filter status, activate a remote temporary occupancy switch, and/or used as a general purpose service
indicator. The two models contain a SPST auxiliary switch, which can be used to control lighting or disable the
economizer function and a discharge air sensor input.

The thermostats are also compatible with the new Vykon PIR cover accessories. Thermostats equipped with
a PIR cover provide advanced active occupancy logic, which will automatically switch occupancy levels from
Occupied to Stand-By and Unoccupied as required by local activity being present or not. This advanced
occupancy functionality provides advantageous energy savings during occupied hours without sacrificing
occupant comfort. All thermostats can be ordered with or without a factory installed PIR cover ( see ordering
notes below ).

The additional following documentation is available:

• VYKONStat PIR Ready VT76xx Series BACnet Integration Guide

• VYKONStat PIR Ready VT6x7 Series LonWorks Integration Guide

• VYKONStat PIR Application Guide

• VYKONStat PIR Cover Assembly Installation Guide

• VYKONStat Wireless Controller Application Guide

Models Available

Application 2 Heat / 2 Cool

Model (programmable) VT7657B5x28(X)

Model (non-programmable) VT7607B5x28(X)

Ordering Information Notes:

- (X) model number represents available communication options: X=none for Stand-alone, X=B for BACnet MS-TP, X=E for Echelon and X=W for

Wireless

- Thermostats can be ordered with a factory installed PIR cover. Please use (5500) extension instead of the (5028) only extension.: Ex. VT7607B5500E.

- Thermostats ordered without a PIR cover can be retrofitted with a separate PIR accessory cover afterwards when required

Features and benefits

Features Benefits

• Advanced occupancy functions ⇒ Through the network or smart local occupancy sensing

• Ready for PIR accessory cover ⇒ Fully integrated advanced occupancy functionality with

a PIR accessory cover

• Embedded humidification sequence (0-10 Vdc output)

⇒ Simplifies installation and reduce installation costs

and dehumidification sequence (dry contact)

• Internal embedded RH sensor ⇒ Eliminates components

• Proportional RH high limit override ⇒ Prevents costly damage due to over-humidification

• Humidity setpoint reset based on outdoor temperature ⇒ Saves energy and prevents window condensation in

colder climates

• PI time proportioning algorithm ⇒ Increased comfort , accuracy, and energy savings

• 1 digital input ⇒ Adds functionality

• Smart fan ⇒ Saves energy during night mode

• Unique configuration key with password protection ⇒ Minimizes parameter tampering

• 6 hour reserve time for clock ⇒ No need to reprogram day/time after power shortage

• Remote outdoor temperature sensor ⇒ Increase flexibility and functionality

• Auxiliary output ⇒ Can be used for lighting and/or economizer override

• Discharge air humidity sensor ( 0-10 Vdc input ) ⇒ Can be used to limit supply RH levels

• Intuitive, menu-driven programming (7 day, 2/4 events -

on programmable models only)

⇒ Can be used for all types of establishments

2

Theory of operation

The VT76x7 uses a Viconics proprietary adaptive logic
algorithm to control the space temperature. This
algorithm controls the heating / air conditioning system
to minimize overshoots while still providing comfort. It
provides exceptional accuracy due to its unique PI
time proportioning control algorithm, which virtually
eliminates temperature offset associated with
traditional, differential-based on/off thermostats.

Fig.2 - On/Off mechanical control vs PI electronic control.

Features overview

• 7 day programmable models, 2 or 4 events

• Gas/oil or electric system compatibility for all type

of applications

• Internal RH sensor and remote RH input with

humidification and dehumidification sequence of
operation embedded

• Remote outdoor sensing capability for added

flexibility

- System mode lock out

- Humidity setpoint reset

• High limit input to prevent over-humidification

• Lockable keypads for tamper proofing. No need for

thermostat guards

• Automatic frost protection to prevents costly freeze

damage

• Anti short cycle and minimum on/off run time

protection. Reduces wear and maximizes life span

of mechanical equipment.

• Programmable digital input for added flexibility. The

input can be programmed as the following:

- None: No function will be associated with the

input

- Service: a backlit flashing Serv

ice alarm will be

displayed on the thermostat LCD screen when
the input is energized. It can be tied in to the AC
unit control card, which provides an alarm in

case of malfunction.

-

Filter: a backlit flashing Filter alarm will be

displayed on the thermostat LCD screen when the
input is energized. It can be tied to a differential

pressure switch that monitor filters

- Rem NSB: remote NSB timer clock input. Will

disable the internal scheduling of the thermostat.
The scheduling will now be set as per the digital
input. The menu part related to scheduling is
disabled and no longer accessible. It provides low
cost setback operation via occupancy sensor or
from a dry contact

- RemOVR: temporary occupancy contact. Disables

all override menu function of the thermostat. . The
override function is now controlled by a manual
remote momentarily closed contact. When
configured in this mode, the input operates in a
toggle mode.

With this function enabled it is now possible to
toggle between unoccupied & occupied setpoints
for the amount of time set by parameter
(TOccTime) temporary occupancy time.

Fan lock: used in conjunction with a local airflow

sensor connected to the input. Locks out the
thermostat heating and cooling action and displays
a local alarm if no air flow is detected 10 seconds
after the fan ( G terminal ) is energized.

• Programmable smart fan operation saves

energy during night mode

• Non volatile EEPROM memory prevents loss of

parameters during power shortage

• Built in default profile set-up for easier start up

and commissioning

• Configurable SPST output relay on

programmable models for lighting, exhaust fan
or fresh air control

• 6 hour typical reserve time for clock in case of

power loss

• 0 to 10 Vdc humidification output

- Built in proportional humidity controller

- Proportional humidity high limit when used
with the analog input for supply humidity

- Automatic humidity setpoint reset when
outside air temperature value is used.

3

Installation

4

• Remove security screw on the bottom of thermostat cover.

• Open up by pulling on the bottom side of thermostat.

• Remove Assembly and wiring terminals from sticker. (Fig. 3)

• Please note the FCC ID and IC label installed in the cover upon

removal of cover for the wireless products.

A) Location:

1- Should not

be installed on an outside wall.
2- Must be installed away from any heat source.
3- Should not be installed near an air discharge grill.
4- Should not be affected by direct sun radiation.
5- Nothing must restrain vertical air circulation to the thermostat.

B) Installation:

1- Swing open the thermostat PCB to the left by pressing the PCB

locking tabs. (Fig. 4)

2- Pull out cables 6” out of the wall.
3- Wall surface must be flat and clean.
4- Insert cable in the central hole of the base.
5- Align the base and mark the location of the two mounting holes

on the wall. Install proper side of base up.

6- Install anchors in the wall.
7- Insert screws in mounting holes on each side of the base.

(Fig. 4)

8- Gently swing back the circuit board on the base and push on it

until the tabs lock it.
10- Strip each wire 1/4 inch.
11- Insert each wire according to wiring diagram.

13- Gently push back into hole excess wring (Fig. 5)
14- Re-Install wiring terminals in correct location. (Fig. 5)

15- Reinstall the cover (top side first) and gently push back extra

wire length into the hole in the wall.
16- Install security screw.

• If replacing an old thermostat, label the wires before

removal of the old thermostat.

• Electronic controls are static sensitive devices.

Discharge yourself properly before manipulation and
installing the thermostat.

• Short circuit or wrong wiring may permanently damage

the thermostat or the equipment.

• Anti-short cycling can be set to 0 minutes for equipment

that posses their own anti cycling timer. Do not use that
value unless the equipment is equipped with such
internal timer. Failure to do so can damage the
equipment.

• All VT7000 series thermostats are to be used only as

operating controls. Whenever a control failure could
lead to personal injury and/or loss of property, it
becomes the responsibility of the user to add safety
devices and/or alarm system to protect against such
catastrophic failures.

Fig.3

Fig.5

Fig.4

Re-install terminal blocks

Thermostat assembly

(VT7600B5x28 shown)

Fig.6

Wiring identification & screw terminal arrangement

Part Number VT7657B5x28(X) VT7607B5x28(X)

Programmable Yes No

Top left terminal block

Y2 X X

Y1 X X

G X X

RC X X

C X X

Top right terminal block

RH X X

W1 X X

W2 X X

Bottom terminal block

HUM X X

AUX X X

DEHUM X X

DI X X

HS X X

SCOM X X

OS X X

HL X X

5 pole left top connector

Y2

RCGY1

8 pole bottom connector

DE

HUM

AUX

HUM

DI

3 pole left top connector

C

HS OS

W1RH

S
COM

Detailed wiring diagrams for selected models

VT76X7B5X28(X)
2 Heat / 2 Cool / Humidifier & Dehumidifier Outputs / Programmable & Non-Programmable

Jumper J1

Y2 Y1

See note 1
(previous
page)

RCG C

W1RH W2

HUM AU

DeHum

Digital Input

DI HS

Scom

W2

HL

OS

5

HL

Cool

Stage 2

Cool

Stage 1

Thermostat internal wiring
System wiring
Jumper J1

Fan

24 Vac

T1

Heat

Stage 1

Heat

Stage 2

0-10 Vdc

Com24V

Auxiliary

Output

Dehum

Output

0-10 Vdc
Remote
Humidity

Sensor

Field contact

Remote
Outdoor

Sensor

0-10 Vdc

High Limit

Humidity

Sensor

Wiring notes:
Note 1: If the same power source is used for the heating stages, install jumper across RC & RH. Maximum current is 2.0

amps.

Note 2: If auxiliary output is used to toggle occupancy of the electronic control card inside the equipment, configure the

relay parameter (Aux cont ) to the N.O. setting. A second relay can be added for additional functionality of the
occupancy output.

Note 3: Humidifier output uses a half bridge rectifier. Reference of the control signal is the common of the power supply of

the thermostat. (terminal C)

Note 4: Electromechanical contact are to be used with the digital input. Electronic triacs cannot be used as mean of

switching for the input. The switched leg to the input for the input to activate is terminal C ( common )

Note 5: The transformer of the unit provides power to the thermostat and the additional loads that will be wired to the

thermostat.

Remote humidity sensor accessories

Model no. Description

VH2020W1028 Wall mounted humidity sensor
VH2020D1028 Duct mounted humidity sensor

VH2020W1028, remote wall mounted room humidity sensor.
This sensor can be used for:

• Remote return or room air humidity sensing with the

sensor mounted on the wall.

Fig.7– VH2020W1028
Remote wall mounted sensor

VH2020D1028, remote duct mounted humidity sensor c/w

junction box.

This sensor can be used for:

• Remote return air humidity sensing with the sensor

mounted on the return air duct.

• Supply air humidity sensor used as a high limit

protection.

6

Wiring example of remote room humidity sensor:

VT76x7 Series
Thermostat

C

RC

HL

OS

Scom

HS

DI

24 Vac Power
To Thermostat

VH2020W1000
Remote wiring

1

Common

2

Power

0-10 Vdc

4

Fig.9 – VH2020D1028
Remote duct mounted humidity sensor

Wiring example of duct humidity sensor:

VT76x7 Series
Thermostat

C

RC

HL

OS

Scom

HS

DI

Valid for both hight limit sensor (HL) or
main remote humidity sensor (HS) connections

24 Vac Power
To Thermostat

VH2020D1000
Remote wiring

1

Common

2

Power

0-10 Vdc

4

User menu flow chart:
NOTE:

Prompts may not all be present depending on model selected

MENU

If statu s is:
Unoccupied

7

Over ri de
schd Y/ N

If statu s is:
Temporary Occupied Time,
Occupied hold or

Resume
schd Y/ N

Unoccupied hold

Temperat
set ? Y/ N

Humi d i t y
set ? Y/ N

Sys mode
set ? Y/ N

Off
Heat
Cool

Fan mode
set ? Y/ N

On
Smart
Auto

Auto

Dehumi di
set ? Y/ N

Humi d i f i
set ? Y/ N

Exi t ?
Y/ N

RH% RH%

Cooling
set ? Y/ N

Heat i ng
set ? Y/ N

Unocc CL
set ? Y/ N

Unocc HT
set ? Y/ N

Temperature Temperature Temperature Temperature

Schedul e
set ? Y/ N

°F/°C
set ? Y/ N

°C
°F

Cl oc k
set ? Y/ N

Ti me
set ? Y/ N

Time

Exi t ?
Y/ N

Schedul e
hol d Y/ N

Resume
Occ Hold
Uno Hold

Da y
set ? Y/ N

Day

On stand-alone
models only

Exi t ?
Y/ N

12/ 24hrs
set ? Y/ N

12 / 24

Exi t ?
Y/ N

Exi t ?
Y/ N

Sunday
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Sat ur da y
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Fr i da y
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Thur sday
set ? Y/ N

Oc cupi e d
day? Y/ N

Oc cupi e d
12: 00 pm

Time

Unoccup
12: 00 pm

Time

We dnesda
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Tuesday
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Monday
set ? Y/ N

Occupi ed
day? Y/ N

Occupi ed
12: 00 pm

Time

Unoccup
12: 00 pm

Time

Programming and status display instructions

1. Status display

The thermostat features a two-line, eight-character display. There is a low-level backlit level that is always active and can only
be seen at night. When left unattended, the thermostat has an auto scrolling display that shows the actual status of the
system. Each item is scrolled one by one with the backlighting off. Pressing any key will cause the backlit to come on.

Sequence of auto-scroll status display:

Room Temp &

Humidity

x.x °C or °F Monday Sys mode Occupied Outdoor Service
xx % RH 12.00 AM auto x.x °C or°F

If humidity display is
enabled

RoomTemp
x.x °C or °F

If humidity display is not
enabled

Clock status System mode Schedule status

Sys mode
off
Sys mode
heat

Sys mode
cool

Occupied
hold
Unoccup

Unoccup
hold
Override

Outdoor

temperature

Frost ON

SetClock

Filter

Fan lock

Alarms

Manual scroll of each menu item is achieved by pressing the Yes (scroll) key repetitively. The last item viewed will be shown on the
display for 30 seconds before returning to automatic scrolling. Temperature is automatically updated when scrolling is held.

Outdoor air temperature display is only enabled when outdoor air temperature sensor is connected or a network value is
received.

• A maximum range status display of 50 °C (122 °F) indicates a shorted sensor. Associated functions, such as mode lockouts

are automatically disabled.

• A minimum range status -40 °C (-40 °F) is not displayed and indicates a opened sensor or a sensor not connected.

Associated functions, such as mode lockouts are automatically disabled.

If alarms are detected, they will automatically be displayed at the end of the status display scroll. During an alarm message
display, the backlit screen will light up at the same time as the message and shut off during the rest of the status display. Two
alarms maximum can appear at any given time. The priority for the alarms is as follows:

Frost ON
SetClock
Service
Filter
Fan lock

Indicates that the heating is energized by the low limit frost protection room temperature setpoint 5.6 °C (42 °F )
Indicates that the clock needs to be reset. There has been a power failure which has lasted longer than 6 hours
Indicates that there is a service alarm as per one of the programmable digital input (DI1 or DI2)
Indicates that the filters are dirty as per one of the programmable digital input (DI1 or DI2)
Indicates that the heating and cooling action are locked out due to a defective fan operation

Three status LEDs on the thermostat cover are used to indicate the status of the fan, a call for heat, or a call for cooling.

• When the fan is on, the FAN LED will illuminate.

• When heating is on, the HEAT LED will illuminate.

• When cooling is on, the COOL LED will illuminate.

Fig.10 – VT7657 and VT7607 cover

8