10
C6.1.10/0118-0318/E
Fixed high-pressure switches:
This is a non-adjustable protection device designed to prevent
the compressor from operating outside of its safe high-pressure range. Reset is automatic for a
set number of trips (7) then the unit will lock out and require manual restart. This feature is
important to prevent the unit from cycling under these controls for a long period of time.
▪
Cut-out:
28.8 bar
▪
Cut-in:
24 bar
Adjustable high-pressure limitation:
The unit controller provides the possibility to stop the unit
at a required discharge pressure which is lower than the cut-out value of the fixed high-pressure
switch. Detailed instructions can be found in chapter 2.10.4 "Additional features for customization"
hereunder.
Discharge temperature protection:
Each unit is equipped with a discharge line sensor (NTC).
The XCM25D controller will stop the compressor if discharge temperatures reach unacceptable
levels.
Adjustable low-pressure alarm:
The unit controller features an adjustable low-pressure alarm
managed by the suction pressure sensor. This alarm has been factory-set at 0.5 bar(rel), ie, the
lowest permitted pressure of the refrigerant with the lowest pressure-vapour properties. If needed
the user can modify this value according to the required application.
Option: Adjustable low-pressure switches PS1:
This device protects the system against low-
pressure operation. It must be adjusted depending on running conditions and potential special
requirements like pump-down. The compressor envelopes published in Select must be respected
at all times. In case of controller breakdown, the low-pressure switch could be used for emergency
operation (rewiring required).
A crankcase heater
is directly connected to the controller. The crankcase heater will be energized
when the ambient sensor is below a given value (10°C) and the compressor has been off for a
period of time (5 minutes). The minimum off time does not apply at initial power-up.
In addition to the above, the ZXDI indoor condensing unit has the following features:
▪
Liquid line assembly (filter drier and sight glass/moisture indicator)
▪
Anti-corrosion treatment to the condenser fins
The electronic controller is also the base controller for the connection of many optional and
customer supplied functions such as:
▪
Main load controller
▪
Evaporator fan contactor
▪
Superheat controller for one electronic expansion device
2.10.4 Additional features for customization
A lot of additional features are provided by the XCM25D controller. In the European design of the
electrical panel a few of the additional functionalities are prearranged and can easily be installed
by connecting additional hardware to the electrical terminals. The tables in
Appendix 6
show the
parameters that have to be changed in case a special feature of the controller should be activated.
The tables do not show the required settings which have to be done by the system operator, eg,
choosing correct setpoints for different components and different applications.
NOTE: After programming an additional function, the system will have to be restarted. To
engage system restart, switch off the main power supply, wait for 5 seconds and switch it
on again.
Component
Description
Prearranged terminals /
Wiring diagram
B12
Low-pressure switch, optional; can be
ordered factory-installed.
Terminals: X1.
2
/ X1.
7
Alarm contact
Sensor for evaporator or room
Terminals: X1.
11
/ X1.
12
Sensor B7
Sensor for evaporator or room
(NTC10k
Ω)
Terminals: X1.
13
/ X1.
14
Table 7: Prearranged additional connections
Содержание Copeland EazyCool ZXDI Series
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