Pre-Rotation Vanes Potentiometer - Johnson Controls YORK OPTIVIEW YK Series Service Instructions Manual

SECTION 22 - HOT GAS BYPASS
This board must be configured properly for the Hot gas
control. The on-board Program Jumpers must be con-
figured as follows:
JUMPER
J1 and J2
J25 and J26
J13, J39 and J40
A 499 ohm, 1%, ½w resistor is connected between P10-
2 and P10-5 to convert the 0 to 20mA output to a 0 to
10VDC output required for the Hot gas valve Actuator.
I/O Board 031-02895-000
This board communicates with the microboard COM3
serial port using Modbus protocol. It is only compat-
ible with Microboard 031-02430-000/-001 equipped
with software version C.OPT.01.21.307 (or later). It
is not compatible with Microboard 031-01730-000 or
any previous software versions. Refer to Figure 72 on
Page 190.
If the chiller is equipped with Heat Recovery or Head
Pressure Control, theses features are also interfaced to
this board. All Chillers supplied with the Heat Recov-
ery feature are also supplied with the Hot gas bypass
feature.
Service Replacement
Replace the defective board with the same part number
board. This prevents any compatibility issues.
188

PRE-ROTATION VANES POTENTIOMETER

A 2.5K ohm potentiometer, mounted on the Pre-rota-
tion Vanes control arm, provides a 0 to 5VDC voltage
that represents a PRV position of 0% (fully closed) to
POSITION
100% (fully open) as displayed on the Hot gas bypass
pins 2 and 3
Screen. To assure accuracy, a PRV calibration proce-
pins 2 and 3
dure must be performed as detailed in SECTION 32 -
pins 1 and 2
SYSTEM CALIBRATION, SERVICE SETPOINTS AND
RESET PROCEDURES of this manual.
The potentiometer could be connected to the Vari-
able Speed Drive (VSD) Adaptive Capacity Control
(ACC) Board, Analog I/O Board 371-02514-000 or
Microboard 031-02430-001. The actual connection
point is determined by the motor drive type and hard-
ware configuration as follows:
• If starter type is VSD, the potentiometer is con-
nected to either the ACC Board or the microboard,
depending upon where the ACC function is per-
formed. If the ACC board is present it is con-
nected to the ACC Board J4. If the ACC Board
is not present (ACC function performed in the
microboard) it is connected to the microboard J7.
• If the starter type in not VSD, the potentiometer
is connected to either the Analog I/O Board or
Microboard depending on which I/O Board is
present. If Analog I/O Board 371-02514-000 is
present, it is connected to this board at P1. If I/O
Board 031-02895-000 is present, it is connected
to the microboard J7.
FORM 160.54-M1
JOHNSON CONTROLS