C6.1.6/0117-1017/E
15
Parameter
Description
Factory settings /
Range
Recommended settings / Comments
G04
Case temperature
lower limit G02
-10°C
/ -40°C to G05
Define limits to avoid wrong operator
settings for G02
G05
Case temperature
upper limit G02
+15°C
/ G04 to 110°C
Define limits to avoid wrong operator
settings for G02
G06
Emergency run
on-time
2 min / 0 to 255 min
In case of probe failure, the compressor
will cycle for a time defined by G06 & G07
G07
Emergency run
off-time
1 min / 0 to 255 min
In case of probe failure, the compressor
will cycle for a time defined by G06 & G07
Table 11: External temperature sensor
– Parameters
Please check that
G56
is set to
"NO"
(means "no solenoid valve in the liquid line") and no additional
digital inputs are configured (Digital Input DI3; Parameter R07 has to be set to "not used" =
nu
= 0).
Adjustable discharge pressure limitation
The controller has dedicated parameters to provide the possibility of adjustable discharge pressure
cut-out.
Parameter
Description
Factory settings
Recommended
settings
E58
Condenser temperature / Pressure
threshold for high alarm
27
Required value
E61
Condenser temperature / Pressure
threshold for alarm recovery
23
Required value
Table 12: Discharge pressure limitations
Low ambient operation
Very low ambient temperatures can result in malfunction of expansion devices because of insufficient
pressure difference. Therefore, pressure cut-out during system start-up can occur. For proper
operation of the expansion devices, the unit running time must allow to build up sufficient condensing
pressure.
At low ambient conditions, the compressor will need to run for a minimum period of time to allow the
system pressures to stabilize. If the unit operates below a defined ambient temperature (ambient
temp. <
C12
) or if the ambient sensor has failed, the compressor should run for a set period of time
(
C14
) when it is started based on a low suction reading.
The unit will be turned on for the minimum run time in the following cases:
▪
a room thermostat input is closed
▪
the case temperature setting cut-in is reached
▪
the low-pressure input is closed,
The unit will start in any of these cases even if parameter
G56
is set to true, ie, the thermostat or
case temperature controls the liquid line solenoid.
If the pressure drops below the cut-out value or the low-pressure input opens, the unit should
continue to run for the remaining minimum on time (
C14
) or until a satisfactory condenser pressure
is reached (
C13
).
If a suction pressure transducer is present and the suction pressure falls below a given value (
C15
)
during the minimum on time (
C14
), then disregard the timer and shut the compressor off to protect
against vacuum operation.
Defrost
The XCM25D is able to control defrost on evaporators. The controller can handle electrical defrost
or natural / fan defrost (select with parameter
G17
). The defrost probe (parameter
G12
) provides the
XCM25D with information about the temperatures in the evaporator.
The intervals between defrost cycles are controlled by parameter
G23
. This can be done by means
of the integrated real time clock or by fixed intervals.
S
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P
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Inst
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Ma
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Dismant
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