WIRING – MAIN POWER

These units are rated for 60/50 Hz operation as follows.

NOTE: This system must be controlled only by the Bard 8403-064 Digital Thermostat/Controller that is supplied with the unit. See below for Wiring and Pages 16-17 for Operating Sequences.

 

Volts

Operating

Electrical

Hz

Voltage

Code

Phase

Range

 

 

 

-R

230/208-60-1

197 - 253

220/200-50-1

180 - 242

 

 

 

 

-S

230/208-60-3

197 - 253

220/200-50-3

180 - 242

 

 

 

 

-T

460-60-3

414 - 506

400-50-3

360 - 440

 

 

 

 

Refer to the unit rating plate for wire sizing information and maximum fuse or “HACR” type circuit breaker size. Each outdoor unit is marked with a “Minimum Circuit Ampacity”. This means that the field wiring used must be sized to carry that amount of current. Depending on the installed KW of electric heat, there may be two field power circuits required. If this is the case, the unit serial plate will so indicate. All models are suitable only for connection with copper wire. Each unit and/or wiring diagram will be marked “Use Copper Conductors Only”. These instructions must be adhered to. Refer to the National Electrical Code (NEC) for complete current carrying capacity data on the various insulation grades of wiring material. All wiring must conform to NEC and all local codes.

The electrical data lists fuse and wire sizes (75° C copper) for all models including the most commonly used heater sizes. Also shown are the number of field power circuits required for the various models with heaters.

The unit rating plate lists a “Maximum Time Delay Relay Fuse” or “HACR” type circuit breaker that is to be used with the equipment. The correct size must be used for proper circuit protection and also to assure that there will be no nuisance tripping due to the momentary high starting current of the compressor motor.

The disconnect access door on this unit may be locked to prevent unauthorized access to the disconnect. To convert for the locking capability, bend the tab located in the bottom left-hand corner of the disconnect opening under the disconnect access panel straight out. This tab will now line up with the slot in the door. When shut, a padlock may be placed through the hole in the tab preventing entry.

See “Start Up” section for important information on three phase scroll compressor start ups.

See Table 3 for Electrical Specifications.

WIRING – LOW VOLTAGE WIRING

230/208V, 1 phase and 3 phase equipment dual primary voltage transformers. All equipment leaves the factory wired on 240V tap. For 208V operation, reconnect from

240V to 208V tap. The acceptable operating voltage range for the 240 and 208V taps are:

TAP

RANGE

240

253 – 216

208

220 – 187

NOTE: The voltage should be measured at the field power connection point in the unit and while the unit is operating at full load (maximum amperage operating condition).

DIGITAL THERMOSTAT/CONTROLLER

Terminal

Function

Type

Form

 

 

 

 

+B

MSTP + (not used)

Communications

 

 

 

 

 

-A

MSTP - (not used)

Communications

 

 

 

 

 

IN4

Outdoor Temperature Sensor

Input

10K OHM Type 3

 

 

 

 

IN3

Pressure Transducer

Input

0-5 VDC, 0-700 PSIG

 

 

 

 

GND

Sensor Grounds

Input

 

 

 

 

 

IN2

Lockout Alarm

Input

Relay Closure

 

 

 

 

24 COM

24VAC Com

Power

 

 

 

 

 

24V

24VAC

Power

 

 

 

 

 

OUT 9

Fan Motor Control

Analog Output

0-10VDC

 

 

 

 

GND7-9

Control Ground

Analog Output

 

 

 

 

 

OUT 8

Unloader Solenoid Control

Analog Output

0 or 5VDC PWM

 

 

 

 

OUT 7

Blower Motor Control

Analog Output

0-10VDC

 

 

 

 

RLY 4

Heater Contactor #1

Relay Output

Relay

 

 

 

 

SC 4-6

24VAC to Relay Outputs 4-6

Power

 

 

 

 

 

RLY 5

Heater Contactor #2

Relay Output

Relay

 

 

 

 

RLY 6

(not used)

 

 

 

 

 

 

RLY 3

(not used)

 

 

 

 

 

 

SC1-3

24VAC to Relay Outputs 1-3

Power

 

 

 

 

 

RLY 2

Compressor Contactor

Relay Output

Relay

 

 

 

 

RLY 1

(not used)

 

 

 

 

 

 

8403-066 DIGITAL

 

CONTROLLER

UNIT LOW

+B

OUT 9

VOLTAGE

TERMINAL

-A

GND 7-9

BLOCK

IN4

OUT 8

F

IN3

OUT 7

 

GND

RLY 6

E

IN2

SC 4-6

 

24 COM

RLY 5

 

24V

RLY 4

Y1

RLY 3

 

SC 1-3

G

RLY 2

 

RLY 1

W1

 

 

W2

 

Y

 

R

 

C

 

1

 

2

 

3

 

4

 

5

 

6

 

7

 

MIS-2852 C

Manual

2100-538E

Page

13 of 23

Page 13
Image 13
Bard W3RV1, W6RV1 Wiring Main Power, Wiring LOW Voltage Wiring, TAP Range, 240 253 208 220, Digital THERMOSTAT/CONTROLLER