IM 1044-2
Centrifugal Chillers
29
Full Metering Option
Remote mounted wye-delta, solid state, and across-the-line
starters require field wiring to activate the optional ammeter
display or full metering display option on the chiller’s operator
interface panel. The wiring is from the MX3 board in the starter
to the compressor controller.
Figure 18, Wiring for Optional Display
NOTES:
•
The serial card location is in the lower-center of the compressor controller located in the chiller control panel.
•
The “MX3” is located in the starter.
•
The connections are (-) to (-), (+) to (+) and SCOM to GND with s shield connection on the starter terminal board.
•
Cable is Belden 9841 or equal (120 OHM characteristic impedence)
Control Power Wiring Options
The control circuit on the
Daikin
centrifugal packaged chiller is designed for 115-volts. Control power
can be supplied from three different sources:
1.
If the unit is supplied with a factory-mounted starter or VFD, the control circuit power supply is
factory-wired from a transformer located in the starter or VFD.
2.
A freestanding starter or VFD furnished by
Daikin
, or by the customer to
Daikin
specifications, will have a control transformer in it and requires field wiring to terminals in the
compressor terminal box.
3.
Power can be supplied from a separate circuit and fused at 25 amps inductive load. The control
circuit disconnect switch must be tagged to prevent current interruption.
Other than for service
work, the switch is to remain on at all times in order to keep oil heaters operative and
prevent refrigerant from diluting in oil.
DANGER
If a separate control power source is used, the following must be done to avoid severe personal injury or death from
electrical shock: Place a notice on the unit that multiple power sources are connected to the unit.
Place a notice on the main and control power disconnects that another source of power to the unit exists.
Wiring Connection on Starter for Optional Display