National Lab OCGE 111, Operating And Maintenance Manual

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8
Legend:
1 Compressor
2 Condenser
3 Expansion valve
4 Evaporator
5 Pump
6 Consumer
7 Tank
3.3.4 SINGLE-CIRCUIT SYSTEM WITHOUT TANK
The cooling medium circuit is designed as a single-circuit system without tank. The pump conveys the cooling me-
dium inside the circuit through the evaporator and through the consumer.
The cooling medium in cooled inside the evaporator. The circuit consists of the following components:
§
pump of horizontal or vertical design,
§
piping system consisting of copper or plastic pipes with manometer and probe connection for the operating
thermostats and the digital temperature display.
If designed as a system closed to the atmosphere, the external circuit must be provided with venting connec-
tions and with pressure compensation tank if required!
Legend:
1 Compressor
2 Condenser
3 Expansion valve
4 Evaporator
5 Pump
6 Consumer
3.4 ELECTRIC CIRCUIT
3.4.1 STANDARD COMPONENTS USED IN THE CHILLER
ALR Ø Composite Failure Report
The composite failure report summarizes all fault messages from the compressor, the pump(s), fan(s) of the high-
pressure and low-pressure pressostats, the flow monitor as well as the breakage of probes. Voltage-free series
connection of this composite report takes place at the terminals in the switch cabinet (see circuit diagram in the
Annex).
IG Ø Main switch
The chiller carries no current after it has been turned off with the main switch. The switch is located on the door of
the switch cabinet.
MTC Ø Motor protection switch for compressor
If the motor current increases beyond the set value or if there is a short circuit, the motor protection switch turns
off and interrupts the current supply. The motor protection switch has to be turned on manually after the cause of
the malfunction has been eliminated. The motor protection switch is located in the switch cabinet.
MTP Ø Motor protection switch for pump
If the motor current increases beyond the set value or if there is a short circuit, the motor protection switch turns
off and interrupts the current supply. The motor protection switch has to be turned on manually after the cause of
the malfunction has been eliminated.