Installation manual

42 Magnitude™ Frictionless Centrifugal Chillers – Model WMC IM 1029-2
Field Wiring Diagram Notes
1. Compressor front end box is factory mounted and wired. All line side wiring must be wired in accordance
w
ith the nec and be made with copper wire and copper lugs only. Use only copper supply wires with
ampacity based on 75°C conductor rating. Main power wiring between the front end box and compressor
terminals is factory installed.
• Minimum wire size for 115 VAC is 12 ga. for a maximum length of 50 feet. If greater than 50 feet refer to
Daikin for recommended wire size minimum. Wire size for 24 VAC is 18 ga. All wiring to be installed as
NEC class 1 wiring system. All 24 VAC wiring must be run in separate conduit from 115 VAC wiring.
Wiring must be wired in accordance with NEC and connection to be made with copper wire and copper
lugs only.
2. For optional sensor wiring see unit control diagram. It is recommended that DC wires be run separately
from 115 VAC wiring.
3. A customer furnished 24 or 120 VAC power for alarm relay coil may be connected between Unit Terminal
Board (UTB1) terminals 84 power and 81 neutral of the control panel. For normally open contacts wir
e
bet
ween 82 & 81. For normally closed wire between 83 & 81. The alarm is operator programmable.
Maximum rating of the alarm relay coil is 25 VA.
4. Remote on/off control of unit can be accomplished by installing a set of dry contacts between terminals
70 and 54.
5. Thermal dispersion flow switches for the evaporator and condenser are factory mounted as standard and
pr
ovide adequate flow loss protection. If desired, additional flow or pressure differential switches c
an be
c
ustomer supplied, mounted and wired as shown. A factory wired evaporator flow switch is connect
ed
bet
ween EF1 and EF2, and a condenser flow switch between CF1 and CF2. Any additional devices must
be wired in series with them.
If field supplied pressure differential switches are used then these must be installed across the vessel
and not the pump. They must be suitable for 24 VAC and low current application.
6. Customer supplied 115 VAC 20 amp power for optional evaporator and condenser water pump control
power and tower fans is supplied to Unit Control Terminals (UTB1) 85 power / 86 neutral, and equipment
ground.
7. Optional customer supplied 115 VAC 25 VA maximum coil rated chilled water pump relay (EP1 and EP2)
may be wired as shown. This optional will cycle the chilled water pump in response to chiller demand.
8. The condenser water pump must cycle with the unit. A customer supplied 115 VAC 25 VA maximum coil
r
ated condenser water pump relay (CP1 and CP2) is to be wired as shown. Units with free cooling must
have condenser water above 60°F before starting.
9. Optional customer supplied 115 VAC, 25 VA maximum coil rated cooling tower fan relays (C1 – C2
s
tandard, C3 – C4 optional) may be wired as shown. This option will cycle the cooling tower fans in
order to maintain unit head pressure.
10. Auxiliary 24 VAC rated contacts in both the chilled water and condenser water pump starters should be
w
ired as shown.