Case Temperature Controller; Condenser Coil & Ambient Air Thermistors; Other Outputs From The Electronic Board; Liquid Line Solenoid Valve (Not Supplied) - Emerson Copeland EazyCool ZX Series Manual

2.12.2 Case temperature controller

An alternative method of system temperature control can be used. The electronic board accepts
an input from a common commercial thermostat.
Failure/Incident Type
Contact open 30 bar
High-pressure cut-out
Contact close 24 bar
Contact open 1 bar
Low-pressure cut-out
Contact close 2 bar
Discharge gas
overheat
Discharge line sensor
failure
Incorrect phase
Inapplicable for 1~ph
sequence/Loss of
phase
Different settings for different
Over current
In case there is a power
Power cut
Compressor rapid
Minimum 3 minutes OFF time
cycling
If ambient temperature is less
Fresh start program than 38°C when the
compressor is about to start
Compressor intends to start
Electrical failure
but current transformers
(Protector trip)
sense no current
Table 8: Electronic board 2C control reference guide
2.12.3 Condenser coil & ambient air thermistors
These two thermistor type sensors are supplied by Emerson Climate Technologies and
connected to the electronic board for condenser fan speed control. This is usually applicable
where low ambient and (sometimes) low condensing temperatures are likely to adversely affect
refrigeration performance and control.

2.13 Other outputs from the electronic board

2.13.1 Liquid line solenoid valve (not supplied)

An On/Off output connection is provided and wired to the main terminal strip for convenience to
assist the customer for wiring of the liquid line solenoid valve coil into the unit. When the
customer uses LP switch for pull down system, the solenoid valve should be driven by customer
thermostat.
NOTE: The solenoid valve has to be fitted externally by the customer. The solenoid coil
voltage rating is to be 220VAC and the board can accommodate current ratings of 30VA
(hold) or 300VA (inrush). If the rating of solenoid coil is larger than the limit, please use a
proper contactor to control the valve instead of connecting the solenoid coil to board
directly.
10
Setting
Execute STOP program and show out the signal of HP cut-out,
after 3 minutes run normal START program to restart the CDU.
± 1.5 bar
On the 6th request for reset, HP error is set and system will be
locked out.
± 1.5 bar
(HP cut-out)
± 0.5 bar Execute STOP program and show out the signal of LP cut-out,
after 3 minutes run normal START program to restart the CDU.
± 0.5 bar
Execute STOP program and show out the error message, after 3
minutes run normal START program to restart the CDU. On the
DLT over 132°C 6th request for reset, DLT Error is set and system will be locked
out.
(DLT over limit)
If both the discharge line and coil-in sensors are under-range
(80°C and 10°C) after 3 minutes of the compressor starting, show
out the error message. When both the discharge line and coil-in
sensors fail, the error message will be shown.
(DLT thermistor
If 3-phase supply is incorrectly connected to the contactor
terminals, the system will be locked out and show out the error
compressor message.
(Compressor incorrect phase sequence)
Execute STOP program and show out the error message, after 3
minutes run normal START program to restart the CDU. On the
6th request for reset, over current error is set and system will be
compressors
locked out.
(Compressor over current)
Upon the return of power supply, E2 will start the unit on a fresh
start mode.
outage
(Fresh start)
Any start request will be postponed until 3 minutes if the
compressor has stopped within last 3 minutes. If start request is
postponed, the status of compressor will be shown through
diagnosis module.
(Compressor about to start)
Compressor will start for 3 seconds and stop for 20 seconds. This
happens for 3 cycles then the compressor runs continuously.
The status of fresh start is shown through diagnosis module.
Error message will be shown through diagnosis module
Electronic Board Reaction Reset Procedure
5 auto resets are
allowed within 1
hour
5 auto resets are
allowed within 1
hour
Unit will not start
unless it is re-wired
correctly
5 auto resets are
allowed within 1
hour
C6.1.6/1108-0509/E