ECKELMANN UA 410 D, Operating Instruction

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Function of UA 410 D
26 Firmware V1.40 - Doku 2.1 06. April 2016
Defrost termination
Defrosting can be terminated by three methods:
S
Defrost termination temperature obtained on corresponding evaporator temperature sensor, regardless of the
set controller type
S
Expiration of safe defrost time
S
Command via CAN bus (manual command, PC software LDSWin command)
Defrosting is always terminated by the safe defrost time when the defrost termination temperature is
set to ”—”, in which case no ”Defrost Termination By Time” alarm is entered in the message log.
This function is useful with the UR 141 2nd Zone (Z1), for example, when defrosting is to be made
without a defrost heater. R1.3 is a required sensor and therefore a sensor must always be con­
nected in this instance, as the controller will otherwise report sensor break.
Tip : This sensor can be simulated by connecting a fixed resistor (3 to 20k Ohm).
Demand defrosting (controller type UR 141 only)
Demand defrosting means that a scheduled defrost cycle may be initiated or skipped depending on the time
taken for the previous defrost cycle.. Demand defrosting is activated when the counting rate is set other than to
0 and is activated when the counting rate is set to 0.
A defrost counter is set to 6 at the commencement of defrosting and counts down as a function of the set counting
rate as long as temperature on the pilot case evaporator sensor remains in the range from -3
°
C to +3
°
C.
Setting a low counting rate causes the demand defrost counter to count down faster to 1, meaning that all
scheduled defrost cycles are then actually initiated. Setting a high counting rate results in more defrost cycles
being
skipped (maximum 5 cycles).
Waiting time (controller type UR 141 only)
A waiting time can be set to delay initiation of defrosting between the time cooling stops and the time the de-
frost heater starts. This prevents the defrost heater from operating while the evaporator is being pumped down.
Drip time (controller type UR 141 only)
Cooling can be set to restart after a set drain time following defrosting. The drip time does not start until the last
defrost relay has been de-energized, enabling defrost drip water to drain off before cooling restarts.
With the UR 141, the fan remains off until the drip time has expired, the controller then checking whether condi­
tions are fulfilled for starting the fan.
Defrosting with two temperature zones
When two zones are selected for cooling control, each zone is treated separately in defrosting as well. Defrost
start time is however the same for both zones.