Motor Windings; Protection Devices; Crankcase Heaters; Pressure Safety Controls - Emerson Copeland Scroll ZB50KCE Application Manuallines

A molded plug version is available as an option for compressor models ZB50KCE to ZB114KCE
BOM 651 version. The molded plug version is compliant with all CE and safety regulations and its
protection class is IP66.
The benefits of the molded plug version include ease of installation, reduced assembly time and
consequent reduced customer's applied costs. Several conductor cable diameters and lengths are
available.

5.3.1 Motor windings

All the compressor models covered in these guidelines are offered with a three-phase induction
motor. All three-phase motors are connected in star.
The motor insulation material is class "B" (TF*) for all the compressor models. This is according
to VDE 0530, IEC 34-1 or DIN 57530.

5.3.2 Protection devices

Independently from the internal motor protection, fuses must be installed before the compressor.
The selection of fuses has to be carried out according to VDE 0635, DIN 57635, IEC 269-1 or
EN 60-269-1.

5.3.3 Crankcase heaters

IMPORTANT
Oil dilution! Bearing malfunction! Turn the crankcase heater on 12 hours
before starting the compressor.
A crankcase heater is used to prevent refrigerant migrating into the shell during standstill periods.
Due to the Copeland Scroll's inherent ability to handle liquid refrigerant in flooded conditions a
crankcase heater is not required as long as the system charge does not exceed 7.5kg.
Figure 12: Crankcase heater location
5.4

Pressure safety controls

5.4.1 High pressure control

The cut-out setting for the high-pressure control should be determined according to regional
standards, in Europe usually EN 378, part 2.
The maximum pressure value for the individual compressor type, PS high side, is printed on the
nameplate of the compressor.
The high-pressure control should have a manual reset feature for the highest level of system
protection.

5.4.2 Low pressure control

The minimum cut-out setting should be selected according to the refrigerant and to the allowed
operation envelope (see technical data in Select software). For example, a minimum cut-out
setting of 0.3 bar(g) is required for ZF* compressors using R404A.
The low-pressure cut-out should have a manual reset feature for the highest level of system
protection.
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If a crankcase heater is fitted it is recommended that
the heater be turned on for a minimum of 12 hours
prior to starting the compressor. This will prevent oil
dilution and bearing stress on initial start-up. The
crankcase heater must remain energised during
compressor off cycles.
The crankcase heater must be mounted below the oil
Schraeder valve located on the bottom shell – see
Figure 12.
C6.2.27/0716-0219/E