System information

ManualsBrandsAccel ManualsComputer equipmentAV316

IOB (Input/Output Board) — The IOB is supplied

from a 24 VAC supply reference to earth ground. The compo-

nents listed in Tables 2-5 are available at the user’s terminal

block on the IOB. Some are available only if the unit is operat-

ing in Remote mode. Figures 6-9 show IOB wiring diagrams.

Figures 10-13 shows additional control wiring.

LEN Communication Cables — The communica-

tion transmission cables have the following electrical charac-

teristics:

• 2 signal conductors and one ground conductor of 20

AWG or larger, 100% shielded

• One tinned copper braid (65% coverage)

Recommended cables are shown below:

Table 2 — IOB1 Connections at User’s Terminal Block

NOTES:

1. See Fig. 6 for IOB1 wiring diagram.

2. For pressure readings, only Vout (output) terminal is indicated.

See Fig. 6 for Vin (+) and ground (–).

3. Defaults are shown. In some cases the IOB can be configured

differently depending on job requirements.

Table 3 — IOB2 Connections at User’s Terminal Block

NOTES:

1. See Fig. 7 for IOB2 wiring diagram.

2. For pressure readings, only Vout (output) terminal is indicated.

See Fig. 7 for Vin (+) and ground (–).

3. Defaults are shown. In some cases the IOB can be configured

differently depending on job requirements.

USAGE CABLE

Intra-building Belden 8772

High temperature Belden 85240

Plenum Belden 89418

DESCRIPTION CHANNEL TERMINAL TYPE OPTIONAL

Entering Chilled Water Temperature AI1 J16-1,5 5 k —

Leaving Chilled Water Temperature AI2 J16-2,6 5 k —

Entering Condenser Water Temperature AI3 J16-3,7 5 k —

Leaving Condenser Water Temperature AI4 J16-4,8 5 k —

Evaporator Refrigerant Liquid Temperature AI5 J15-6,12 5 k —

Discharge Gas Temperature AI6 J15-5,11 5 k —

Condenser Pressure AI7 J15-4 5 VDC —

Evaporator Pressure AI8 J15-3 5 VDC —

Economizer Pressure AI9 J15-2 5 VDC —

Chiller Running (ON=20mA, OFF=4mA, TRIPOUT=8mA,

READY=12mA)

AO1 J14-1,4 4-20 mA Yes

Chiller Lockout Input DI1 J13-5 24 VAC Yes

Fire Alarm Interlock DI2 J13-6 24 VAC Yes

Remote Contact Input DI3 J13-7 24 VAC Yes

Remote Emergency Stop Input DI4 J13-8 24 VAC Yes

Stage 1 IGV Increase DO1 J12-7 24 VAC —

Stage 1 IGV Decrease DO2 J12-10 24 VAC —

Chiller Alarm DO3 J12-2 24 VAC Yes

Chiller Alert DO4 J12-5 24 VAC Yes

DESCRIPTION CHANNEL TERMINAL TYPE OPTIONAL

Motor Winding Temperature 1 AI1 J16-1,5 5 k —

Motor Winding Temperature 2 AI2 J16-2,6 5 k —

Motor Winding Temperature 3 AI3 J16-3,7 5 k —

Oil Sump Temperature AI5 J15-6,12 5 k —

Oil Pump Discharge Pressure (Oil Supply) AI6 J15-5 5 VDC —

Oil Sump Pressure AI7 J15-4 5 VDC —

Demand Limit Input AI8 J15-3,9 4-20 mA Yes

Refrigerant Leak Detector AI9 J15-2,8 4-20 mA Yes

IGV1 Control Signal AO1 J14-1,4 4-20 mA —

Damper Valve Feedback Fully Open DI1 J13-5 24 VAC —

Damper Valve Feedback Fully Close DI2 J13-6 24 VAC —

High Pressure Switch DI3 J13-7,3 24 VAC —

Ice Build Contact DI4 J13-8,4 24 VAC Yes

Oil Heater Relay DO1 J12-7 24 VAC —

Oil Pump Relay DO2 J12-10 24 VAC —

Economizer Damper Valve Open DO3 J12-2 24 VAC —

Economizer Damper Valve Close DO4 J12-5 24 VAC —