Discharge Line Thermostat - Emerson Copeland ZB12KCU Application Manuallines

3.7.2 Discharge line thermostat

ZB*KCU compressors have no internal discharge gas temperature protection. Therefore, an external
discharge line thermostat must be installed.
Emerson can supply an ATEX discharge line thermostat which can be used with A3 refrigerants. It
can also be used in an ATEX zone 2 or non-ATEX environment. This thermostat is marked with a
special ATEX label – see Figure 11.
Figure 11: ATEX discharge line thermostat and ATEX label
Technical data of the discharge line thermostat
Compressor range
Voltage
Maximum amperage
Operating temperatures
Wire insulation maximum temperature
Clips for tube
Table 8: Discharge line thermostat – Technical data
To be ATEX-compliant, the cable ends of the thermostat must be connected with suitable cable
glands and electrical enclosure to achieve a minimum protection degree of IP54 according to
IEC 60079-15, clause 6.3. When connecting the cable ends, a creepage distance of minimum 4 mm
and a clearance distance of 2.5 mm between the conductive parts at different potentials must be
maintained. Maximal voltage and amps values for the thermostat and a protection against electrical
shock must be respected during the installation.
Additionally, the ATEX compliance requires a protection of the thermostat body against mechanical
damage, according to IEC 60079-0, clause 26.4.2, table 13. There is no need for an additional
housing around the thermostat body. Protection against mechanical damage to the thermostat can
be achieved with an overall cover or box placed around the compressor or refrigerant system.
To ensure proper functioning and to avoid false readings, the discharge line thermostat must be
installed and insulated according to the procedure and recommendations hereunder.
Assembly of the discharge line thermostat
▪ Install the discharge line thermostat on the
discharge tube 120 mm from top cap.
▪ Snap the retainer clip over the tube and onto
the thermostat.
▪ The thermostat should be placed on the
discharge tube so that its body is in upward
position on a horizontal tube installation.
▪ Ensure that the thermostat is not tilted.
▪ The wire must not be in contact with the top
cap of the compressor or the discharge tube.
Care should be taken to route wires so that
they do not come into contact with sharp
objects.
12
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Ø 12.7 mm (1/2")
ZB*KCU
120-240 V AC
5 A / 240 V
134 °C (± 4 K)
106 °C (± 8 K)
150 °C
AGL_Ref_ST_ZBKCU_EN_Rev01