Emerson ZX, User Manual

Page: 34 / 54

through a telephone service to a remote location. Details on how to obtain
diagnostic information from the five module LED’s located on this module
was explained in Section 2.4 and Fig 6. The module is mounted on the
electrical mounting panel, located near the top of the unit and the LED’s can
be easily seen from the front of the unit with the front compressor
compartment panel removed.
The Copeland supplied option - Defrost Control Module. This option provides a
basic, time initiated and time terminated defrost control with additional manual
override (pushbutton). This module is mounted adjacent to the Diagnostic Module and
accessed in the same way.
Compressor Phase Rreversal - ensures that the compressor remains running in one direction
only –very necessary for a compliant scroll compressor to compress and pump refrigerant. Reset
is automatic once the phase rotation is correct for the compressor.
Voltage Protection - ensures that the compressor only operates within the very wide design
voltage tolerance of the three-phase motor.
Motor Current Overload Protection is provided (also via the E2) eliminating the need for
external current protection for the compressor motor.
Fixed Low and High-Pressure Switches . These are non-adjustable protection devices to
prevent the compressor operating outside of its safe evaporating and condensing pressure
range(s). Reset is automatic for a set number of trips, then the unit will lock out and require
manual restart. This latter feature is important to prevent the ZX unit cycling under these controls
for a long period of time.
A Crankcase Heater is wired through a normally closed contact of the compressor contactor in
the usual manner, becoming energized whenever the compressor cycles off.
In addition to the above, the ZX has the following available Options :
Liquid Line Assembly (filter drier and sight glass/moisture indicator) – fitted
Liquid Line Solenoid Valve – supplied loose (mentioned earlier)
Oil Separator – fitted
Suction Accumulator – fitted ( only for Low Temperature models)
Suction Line Filter Drier – supplied loose
Plastic Coated Condenser Fins ( for seaside applications) to order.
Adjustable LP switch for low pressure pump down control - fitted
12.0 Operation & Set-up of the E2 Board
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