Installation manual

IM 1029-2 Magnitude™ Frictionless Centrifugal Chillers – Model WMC 51
Transfer Back to Grid Power: Proper transfer from stand-by generator power back to grid power is essential to
avoid compressor damage.
The procedure for reconnecting power from the generator back to the utility grid is shown below. These
procedures are not peculiar to Daikin units only, but should be observed for any chiller manufacturer.
1. Set the generator to always run five minutes longer than the unit start-to-start timer, which could be set from
15 to 60 minutes. The actual setting can be viewed on the operator interface panel on the Setpoint/Timer
screen.
2. Configure the transfer switch, provided with the generator, to automatically shut down the chiller before
transfer is made. The automatic shut-off function can be accomplished through a BAS interface or with the
“remote on/off” wiring connection shown in the field wiring diagram. A start signal can be given anytime
after the stop signal since the three-minute start-to-start timer will be in effect.
Chiller Control Power: For proper operation on standby power, the chiller control power must remain as
factory-wired from a unit-mounted transformer. Do not supply chiller control power from an external power
source because the chiller may not sense a loss of power and do a normal shutdown sequence.
Building Automation Systems
All MicroTech II controllers with Open Choices™ are capable of BAS communications, providing easy
integration and comprehensive monitoring, control, and two-way data exchange with open standard protocols
such as LonTalk, Modbus or BACnet.
Daikin unit controllers strictly conform to the interoperability guidelines of the LONMARK 
Interoperability Association and BACnet International. They have received LONMARK certification
with optional LONWORKS communication module.
Protocol Options
•
•
BACnet MS/TP
•
•
L
ON
W
ORKS
(FTT-10A)
•
• B
ACnet IP
•
• M
odbus RTU
•
• BACnet Ethernet
The BAS communication module can be ordered with a chiller and factory-mounted or can be field-mounted at
any time after the chiller unit is installed.
Table 19, Typical Data Point Availability
Typical Data Points
1
(W = Write, R = Read)
Active Setpoint R Cond EWT R Evap Water Pump Status R
Actual Capacity
R
Cond Flow Switch Status
R
Liquid Line Refrigerant Pressure
R
Capacity Limit Output
R
Cond LWT
R
Liquid Line Refrigerant Temp
R
Capacity Limit Setpoint
W
Cond Pump Run Hours
R
Maximum Send Time
W
Chiller Enable
W
Cond Refrigerant Pressure
R
Minimum Send Time
W
Chiller Limited R
Cond Sat. Refrigerant
Temp
R Network Clear Alarm W
Chiller Local/Remote R Cond Water Pump Status R Pump Select W
Chiller Mode Output
R
Cool Setpoint
W
Run Enabled
R
Chiller Mode Setpoint W Current Alarm R
Chiller On/Off
R
Default Values
W
Chiller Status
R
Evap EWT
R
Compressor Discharge Temp
R
Evap Flow Switch Status
R
Compressor Percent RLA
R
Evap LWT for Unit
R
Compressor Run Hours
R
Evap LWT for Compressor
R
Compressor Select
W
Evap Pump Run Hours
R
Compressor Starts R Evap Refrigerant Pressure R
Compressor Suction Line
Temp
R
Evap Sat. Refrigerant
Temp
R
Note: Data points available are dependent upon options selected.
!
WARNING
Stop the chiller before transferring supply power from the generator back to the utility power grid. Transferring
power while the chiller is running can cause severe compressor damage.