ECKELMANN UA 400, Руководство по эксплуатации

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Firmware V3.15 21.04.2021 391/401
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11.1.3 Alarm in the event of the absence of a defrost
The Alarm " No Defrost " is generated if the alarm does not take place within an adjustable time. No alarm is
generated if defrosting is suppressed due to high temperature or by demand defrosting.
Master/slave defrost / defrost sequence via CAN bus
If the defrost is not conducted then the alarm message „ No Defrost " is generated by both the master and slave
controller. The generation of this message is coupled to the alarm delay time and thus is automatically sent by
all affected controllers if no defrost takes place.
11.1.4 Sensor break alarm
Alarm is generated after the set delay if the controller detects breakage or short circuit on a sensor (menu
6-2-3).
11.1.5 Suppression of sensor break alarm during defrosting
While defrosting is in progress, temperature sensors and particularly the evaporator sensors may become
heated to a temperature above the limits of the case/cold-room controller's temperature detection range.
Sensor break alarm is accordingly suppressed for the duration of defrosting so as to avoid signalling of false
alarms. The following conditions apply:
Sensor break alarm effective prior to defrosting is NOT suppressed.
Sensor break alarm takes place with the set delay during any drain time that may be defined.
Sensor break occurring during defrosting and persisting beyond termination of defrosting is alarmed when
the set delay expires.
Sensor break alarm suppression is effective with all types of defrost (internal, external, discharge gas,
manual and master/slave defrosting).With internal and manual defrosting, sensor break alarm is suppressed
for the complete safe defrost time regardless of defrosting terminating before that.
If the delay time for the sensor failure alarm is set to zero minutes there is no alarm suppression and the
alarm is generated immediately following detection of the sensor failure. This setting is not recommended
for the continuous operation of the controller!
So as to avoid false alarm, the time delay for No Defrost alarm should not be set too short ( No
Defrost parameter in Menu 6-2-3). When the maximum interval between two set defrost times is 48
hours, for example (Menu 3-2), the No Defrost alarm time delay must be set at least one hour longer,
i.e. to 49 hours.
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For defrost sequence via CAN bus only: In master/slave operation the alarm " No Defrost " can also
mean that a slave no longer has any contact to the master. If a slave fails to receive a signal from its
defrost master for a period longer than 60 minutes, then this message is generated.
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Sensor break alarm is always generated for sensors vital to control functions. In the case of optional
sensors, alarm is only generated when the sensors have not been removed from monitoring by sensor
scan (Menu 6-1).
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In the most unfavourable instance, sensor break alarm is merely postponed. The longest possible
delay would be (2 * T
Sensor break delay
) + T
Defrost
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