Fläkt Woods
8643 GB 2012.11
6
We reserve the right to alter specifications
Installation and Maintenance Instructions
EQKA Cooling unit
Functions, General
The compressor’s capacity is controlled by an external
control signal of 0 – 10V. Its operation is interlocked via
the extract air fan contactor and possibly an outdoor
thermostat as well as via a phase rotation relay. After the
fan starts, the compressors are interlocked for 2 minutes
– delayed start of the compressors (“Startwait 2 min.” is
shown in the display”).
Delayed restart
The compressors cannot start again until after a
300/305/310/315 second idle time (KM1/KM2/KM3/
KM4). During this time “ Startwait 2 min.” flashes in the
display if the relevant compressor needs to be started.
Capacity control (Capac. control)
Compressor 1 has a special high pressure switch for
capacity control.
If the condenser pressure is high, compressor 1 is stopp-
ped and is then allowed to restart after 300 sec.
The text "Capac." alt ”1= capacity control” is shown in
the display while capacity control is in progress.
Compressor protection
Each compressor is protected by a high pressure switch
and motor protection. The compressors are protected
from incorrect phase sequence via a phase-sequence relay.
The oil heater is switched in while the compressors are
not in operation.
Stepping levels
The various compressor steps are switched in at the
following signal levels:
Cooling unit with hot gas bypass
On a 20% control signal, the ICM2 with hot gas valve
starts in the fully open position. The hot gas valve
closes linearly between 2 and 8 V. The KMI starts at 8 V
and the valve opens 40%.
Between 8 and 10 V the valve closes again.
Stepping levels
Stepping out of each step occurs 20%(2.0V) during
stepping level for 2 or 3 compressors and 10% (1.0v)
During the stepping level for 4 compressors.
Group alarm
For all alarms, the group alarm relay is energized for
possible external alarm indication.
Display texts
Line 1 shows the type of Cooler
Cooler KM1-2, Cooler KM1-2 bin.
Cooler KM1-3, Cooler KM1-4 bin.
Signifies that the steps are switched in binary mode.
Lines 2 and 3
Show the in-service status of compressors 1-4
Start, (flashes in the event of time-delayed start of KM)
Run, (operation of KM)
Capac. or capacity control
AlarmH, or AlarmHigh pres
AlarmL, or AlarmLowpres
AlarmQ, or AlarmQ1/term.
(Q=motor protection and term= thermistor.
Line 2 can also show
* 3-Phase alarm *
Line 3 can also show
* Fan stop *
* Startwait 2 min *
Line 4
Shows input control signal as 0 – 100%:
Signal %058.
Press Ato see the compressor running time and possible
control signal to SV1 (valve for hot gas bypass).
Program
The control unit is programmed on delivery and its
settings cannot be changed.
Cooler KM – 4
1 = Capac. 3 = Run
2 = Start 4
= Alarm H
Signal %
082
A
B
ESC
–
+
OK
KM1–4 Run time
(h)
1 = 00242 3 = 00154
2 = 00228
4 = 00125
Signal SV1 %
098
A
B
ESC
–
+
OK
Compressor
3
4
Compressor
2
1
30 %
20 %
1
30 %
2
60 %
40 %
1
60 %
3
90 %
60 %
1 + 2
90 %
4
80 %
Straight-line stepping
Number of compressors
Binary stepping
Number of compressors
