ECKELMANN UA 400 - Page 51

Firmware V3.15
21.04.2021
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Group numbers
The defrost sequence master is automatically in group 1 as it starts the defrost, and if the conditions are met,
will also defrost itself in the process. The number of the group determines the defrost sequence. Numbers can
also be jumped over. If one group has finished defrosting, the group with the next highest number will be
automatically defrosted following the elapse of the delay time set on the master. By remaining in regular contact
with the other controllers on the CAN bus, the DS master has an overview of all the DS slaves and the
corresponding group numbers. The controllers must be configured so that the defrost sequence is carried out in
thedesiredsequence.
Actual values
Under1ActualValues–3Defrostthefollowingactualvaluesforthedefrostsequencecanbefound:
The parameter "DSq Nof. Sl." on the defrost sequence master indicates the number of slaves recognised by the
master. The parameter "DSq Lost Sl." On the DS master shows "lost" defrost sequence slaves: When a
previously available defrost sequence slave can no longer be contacted, then the CAN bus address of the DS
slave which the master first lost contact with during the last defrost is shown here. Otherwise (normal
case)"–"isdisplayed.
Special cases / useful information
Information on the initiation of the defrost sequence
Even if the defrost sequence master does not itself meet the defrost condition (e.g. defrost termination
temperature already reached) at the time the defrost is to be initiated, the defrost of the groups is still
initiated.
Once a defrost has been initiated in master/slave operation this can only be interrupted when the parameter
"DS-Function"issetto"OFF"foraminimumof10secondsandthenresetto"SLAVE",seemenu2-2-1–
Defrost 1. It is generally recommended that this procedure only be employed for commissioning situations
as an interruption of the defrost can result in increased icing.
During a defrost sequence the slave's safe defrost, delay and drip times are retained, the parameters set by
the user on the slave are used.
Defrost start times dependent on the number of groups and their defrost durations
The defrost start times configured in the defrost master must have sufficient time between them. It is not
permitted for the defrost master to initiate a further defrost while the previous defrost is still underway. If, for
example, there are 3 defrost sequence groups each with a safe defrost time of 60 minutes for the slaves, then
the time period between each defrost start on the DS master must be at least 3 hours. If a DS delay time is
configured between the groups, then this time is increased accordingly (in the case of n defrost groups (n-1)
delay times).
Combination with the master/slave function
A defrost sequence slave can also function simultaneously as a master in a master/slave defrost via CAN bus.
Alarms and messages
Thealarm125„NoDefrost"canalsoindicatethatadefrostsequencehasnotbeencorrectlyconfigured.
During the initiation of the defrost sequence via an external defrost timer, the external 230 V signal, as
is customary, may only be applied to the controller, in this case the master controller, for the duration of
the defrost. Only when the defrosting of the master has ended - through the removal of the external
signal - can the other groups begin with their defrost!
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