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© STULZ GmbH – all rights reserved EN/09.2019/G41
cybercool 2 screw original insTrUcTions
High pressure limiter with scale for threshold and
external reset button
adjustment screw for setting threshold
adjustment lock
HP switch
(high pressure limiter)
When the HP limiter triggers, the compressor is switched off
without delay. Before the restart and after the elimination of
the error, the HP switch must be reset by pressing the reset
button.
You can change the action value only after having removed
the adjustment lock. Turning the adjustment screw counter
-
clockwise reduces the action value. One turn approximately
corresponds to an action value change by 1.6 bar.
A check of the tripping function of the high pressure limiter
(e.g. by cutting down the condenser fan and forcing a high
pressure) is not possible without changing the action value,
as there are, on behalf of the C7000 controller, further moni
-
toring functions via the high pressure sensor, which intervene
in the compressor control (high pressure management, com
-
pressor envelope control).
A change of the action value (e.g. by reduction), however,
bears the risk that this one is not exactly readjusted after the
check has been executed. The scale on the case does not
provide sufficient accuracy.
The safety high pressure limiter serves as an additional safety
device, its action value is 0,5 bar above the action value of the
HP limiter.
To push the reset button the housing must be opened. The
reset button is located inside.
LP switch
Check the correct function of the low pressure switch by
stepwise closing the expansion valve of one refrigerant circuit
using the manual mode of the C7000 controller, while the
compressor is running. Check by means of the low pressure
gauge in the compressor section, whether the low pressure
switch trips at 1,1 bar. When the LP switch trips, the com
-
pressor is switched off without delay.
If the pressure switch has tripped too early (e.g. at 2,0 bar),
you can reduce the threshold by turning counterclockwise the
adjustment screw on the top side of the pressure switch after
having removed the adjustment lock. One turn approximately
corresponds to a threshold change by 1,6 bar.
After the compressor pause (default setting: 180 sec.) has
elapsed the compressor is restarted. During the evaluation
LP switch with scale for threshold and pressure
hysteresis for automatic reset
