High Pressure: Pressure Relief Valve; Low-Pressure Safety Switch - Optional; Ambient Temperature Sensor; Alarm Output (Do5) - Emerson Copeland EazyCool ZXDI Series Application Manuallines

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The unit will stop then and restart automatically after a 5-minute delay and after unit
pressure has decreased to 24 bar.
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After 7 successive high-pressure cut-outs over 1 hour, the unit will lock out. In this case a
manual reset will be necessary.

2.18.2 High pressure: pressure relief valve

There is a connection port sideways on the top of the unit liquid receiver for a pressure relief valve.
A 3/8"-NPT connection is used. The pressure relief valve is not factory-assembled.
2.18.3 Low-pressure safety switch – Optional
In a way similar to the high-pressure sensor, the electronic controller registers the switching action
of the adjustable low-pressure switch, which will open in the event of an abnormally low suction
pressure:
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The unit will stop then restart automatically after a 3-minute delay and when the unit reaches
the cut-in pressure level.
The unit is always equipped with a suction pressure transmitter which also takes care for protection
against vacuum operation. The use of the optional low-pressure cut-out will provide the highest
protection level for the unit. In rare instances of controller breakdown, the optional low-pressure
switch would allow to run the unit in emergency mode.

2.18.4 Ambient temperature sensor

An ambient temperature sensor supplied by Emerson is connected to the electronic controller.
This temperature sensor has several functionalities like emergency mode control, lower fan speed
limitation and crankcase heater control. The sensor is located at the housing on the backside of
the compressor compartment.

2.19 Alarm output (DO5)

The digital output DO5 is pre-configured as an alarm contact. The relay (max. 5A, 250V AC) is
activated in case of alarms and lock-outs. Warnings will be shown only on the controller display.
2.20 Fan speed control – Ziehl-Abegg PKE-6 controller
The PKE-6 controller is used for continuous speed control adjustment on the variable voltage
motor of the fan. The electrical protection class of the controller is IP54.
The output signal of the unit controller XCM25D to the fan speed controller PKE-6 is a 0-10V digital
signal. It has two main functions: fan speed control and temperature/pressure control of the
condenser.
The fan speed factory setting is 100% rpm.
Depending on the characteristics of the connected air ducts, eg, presence of elbows, reductions,
grids, and the level of noise produced, the fan speed can be adjusted to an appropriate value
considering the expected unit performance and sound level.
A 10µF start capacitor is required for each fan.
Fan U
speed [V]
100% 230
98% 206
95% 190
87% 170
71% 150
51% 130
37% 110
Table 18: Fan data based on changing frequency/fan speed
20
N Pe Airflow
[rpm] [W] [m
1390 375 5352
1360 373 5237
1320 368 5083
1210 361 4659
985 332 3793
709 257 2730
514 178 1979
3
/h]
C6.1.10/0118-0318/E