ECKELMANN UA 410 D, Руководство по эксплуатации

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Function of UA 410 D
18 Firmware V1.40 - Doku 2.1 06. April 2016
On-off control (UA 111 X Zone 2, UA 111 XP Zone 2 and UR 141 only)
Control is made by one temperature sensor (supply air for UA 111, room air for UR 141). The cooling relay de-
energizes when temperature reaches the setpoint (switch-off value) on the respective temperature sensor. The
cooling relay re-energizes with the set hysteresis.
Cooling relay operation
Operation of the cooling relay takes place according to the cooling safety requirements and is governed by the
controller type selected:
UA 111 X, UA 111 XP, UR 141 Zone 2 (NT): N.O. control, i.e. cooling is OFF when case controller is
de-energized.
UR 141 Zone 1 (LT): N.C. control, i.e. cooling is ON when case controller is de-energized.
4.2.2 Compressor control
4.2.2.1 Control by temperature according to majority
Controller type: UA 111 X only
A maximum of two compressors are controlled by the base load/peak load principle. Control is made by case
temperature through all supply air sensors. The peak load compressor is stopped when temperature has
reached the setpoint (switch-off value) on the majority of the connected supply air sensors (e.g. 3 out of 5).
The base load compressor is stopped when temperature reaches the setpoint on the last supply air sensor. It is
started again when temperature has passed the switching differential on the majority of the supply air sensors.
ON delay always expires consecutively for Compressors 1 and 2, meaning that they will never start simultane­
ously even when two compressors are demanded at once by all sensors.
OFF delay may expire concurrently (when all sensors turn cold at once), meaning that both compressors may
stop.
The peak load compressor is restarted when temperature has passed the switching differential on all supply air
sensors. Base load rotation is provided to avoid varying run times of the base and peak load compressors.
Base load rotation takes place not later than after 3 hours of operation or when the following control operations
occur.
(P = 0 / B = 0)
³
(P = 0 / B = 1) or (P = 1 / B = 1)
³
(P = 0 / B = 1)
P = peak load compressor / B = base load compressor / Transition from one control state to the next.
Both compressors are stopped immediately if the set antifreeze protection temperature is reached. They are
both restarted after an adjustable time delay has elapsed.
4.2.2.2 Antifreeze protection
The supply air sensor on which temperature is the coldest causes cooling to be stopped if temperature drops
below the set antifreeze protection level. This prevents freeze-up and damage to merchandise in individual dis­
play cases controlled at very cold temperature to accommodate special requirements of placement or the like.