CG-SVX17D-EN 85
Installation - Electrical
building” to “ice complete”. When contact 5K16 is provided, the chiller will run normally when the
contact is open.
CH530 will accept either an isolated contact closure (External Ice Building command) or a Remote
Communicated input (Tracer) to initiate and command the Ice Building mode.
CH530 also provides a “Front Panel Ice Termination Setpoint”, settable through TechView, and
adjustable from 20 to 31°F (-6.7 to -0.5°C) in at least 1°F (1°C) increments.
When in the Ice Building mode, and the evaporator entering water temperature drops below the
ice termination setpoint, the chiller terminates the Ice Building mode and changes to the Ice
Building Complete Mode.
NOTICE:
Evaporator damage!
Freeze inhibitor must be adequate for the leaving water temperature. Failure to do so may result
in damage to system components.
TechView may also be used to enable or disable Ice Machine Control. This setting does not prevent
the Tracer from commanding Ice Building mode.
Upon contact closure, the CH530 will initiate an ice building mode, in which the unit runs fully
loaded at all times. Ice building shall be terminated either by opening the contact or based on the
entering evaporator water temperature. CH530 will not permit the ice building mode to be
reentered until the unit has been switched out of ice building mode (open 5K20 contacts) and then
switched back into ice building mode (close 5K20 contacts.)
In ice building, all limits (freeze avoidance, evaporator, condenser, current) will be ignored. All
safeties will be enforced.
If, while in ice building mode, the unit gets down to the freeze stat setting (water or refrigerant), the
unit will shut down on a manually resettable diagnostic, just as in normal operation.
Connect leads from 5K20 to the proper terminals of 1A16. Refer to the field diagrams which are
shipped with the unit.
Silver or gold-plated contacts are recommended. These customer furnished contacts must be
compatible with 24 VDC, 12 mA resistive load.
External Chilled Water Setpoint (ECWS) Option
The CH530 provides inputs that accept either 4-20 mA or 2-10 VDC signals to set the external chilled
water setpoint (ECWS). This is not a reset function. The input defines the set point. This input
is primarily used with generic BAS (building automation systems). The chilled water setpoint set
via the DynaView or through digital communication with Tracer.
The chilled water setpoint may be changed from a remote location by sending either a 2-10 VDC
or 4-20 mA signal to the 1A14, J2-1 and 2. The 2-10 VDC and 4-20 mA each correspond to a 10 to
65°F (-12 to 18°C) external chilled water setpoint.
The following equations apply:
Voltage Signal Current Signal
VDC =
(8*ECWS
°F
+ 2*ECWS
max
- 10*ECWS
min
)/ (ECWS
max
-
ECWS
min
)
mA =
(16*ECWS
°F
+ 4*ECWS
max
- 20*ECWS
min
)/ (ECWS
max
-
ECWS
min
)
Note: To convert ECWS values to °F, use the following formula: °F = 1.8*(°C) + 32
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