Compressor Motor Protection; System Pressure Protection; High-Pressure Safety Switch; High-Pressure: Pressure Relief Valve - Emerson Copeland Eazycool OMTE-90D-TFD Application Manuallines

2.18 Compressor motor protection

The electronic controller protects the compressor motor against the following:
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phase loss
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incorrect phase rotation
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voltage imbalance

2.19 System pressure protection

2.19.1 High-pressure safety switch

A non-adjustable high-pressure switch is protecting the system against too high-pressures.
The device will open in the event of an abnormally high discharge pressure (above 28.8 bar).
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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.

2.19.2 High-pressure: pressure relief valve

There is a connection port sideways on the top of the unit liquid receiver for a pressure relief valve.
It is a thread with 3/8"-NPTF connection. The pressure relief valve is not factory-assembled.

2.19.3 Low-pressure safety switch

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 (D28) 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. In rare instances of controller breakdown, the low-pressure switch would
allow the unit to run in emergency mode (rescue mode).

2.20 Other inputs of the XCM25D controller

2.20.1 Heat recovery mode

The electronic controller provides a digital input (DI5) to activate the heat recovery mode. There are
prewired terminals X11.51 & X11.52 available to connect the demand signal. The wiring between the
controller and above-mentioned terminals is also factory-assembled.

2.20.2 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.
2.20.3 Refrigerant level control – Leak detection device
The liquid receiver is equipped with an external liquid level watch LW4-L120 from Alco. This device
provides a digital signal to the system controller XCM25D in case of low charging level inside the
receiver. In this manner it indicates system leakages in a very early stage.
The LW4-L120 device is connected to the digital input DI3 (terminals X1.65/66/67)
2.20.4 Fan failure – Fan feedback
Due to the introduction of EC fan technology the system controller gets a feedback from the fans
about their conditions. In case of failure the digital input DI7 (terminals X1.55/56/57) is activated and
a fan alarm is indicated
2.21 Output of the XCM25D controller – 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 lockouts. Warnings will be shown only on the controller display.
This setting can be adjusted using parameter S01.
24 C6.1.9/0219/E