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The data inside this manual are not binding and they can be modified by the manufacturer without notice.
All rights reserved.
NPC 280 - 400
7.13.3 Display read-out on unit stopp ed by remote con tro l
From a digital input configured as a remote ON/OFF, when the input is active the OFF command is generated.
The top display shows “
OFF
” with the decimal places LED flashing.
7 . 1 4 C o m p r e s s o r s u n l o a d i n g f u n c t i o n
This procedure is necessary when sudden peaks in cooling demand occur, for instance if the machine is restarted after a long period of inactivity.
Under these conditions the evaporator inlet water temperature might be so high as to require a cooling delivery in excess of system capacity.
The consequent system overload would require the start-up of all the compressors at once, which would be forced to operate in near-limit
conditions.
The overburdened compressors would thus be subject to dangerous overheating which would cause the activation of the thermal protections, or
the pressure of the refrigerant gas could reach alarm levels which would cause the machine to shut down.
This function enables the machine to run (through the switch-off or capacity step operation of the compressors) even when the temperature of the
water at the evaporator’s inlet is high (summer start-up with hot water accumulation), preventing the possible triggering of high pressure alarms.
(see alarm table)
7 . 1 5 P r o b e k e y
In this chapter are indicated the probes
BTWOT
,
BEWOT1
,
BEWOT2, BHP1, BHP2
and
BAT1
, for their positioning consult the refrigerant
drawing.
Their description is indicated in the following table:
Name in the manual
Borne name
Description
-BTWOT
PB2
TANK WATER OUTLET TEMPERATURE PROBE
-BHP1
PB3
HIGH PRESSURE TRANSDUCER OF CIRCUIT 1
-BHP2
PB4
HIGH PRESSURE TRANSDUCER OF CIRCUIT 2
-BEWOT1
PB7
EVAPORATOR WATER OUTLET TEMPERATURE PROBE CIRCUIT 1
-BEWOT2
PB8
EVAPORATOR WATER OUTLET TEMPERATURE PROBE CIRCUIT 2
BAT1
PB9
AMBIENT TEMPERATURE PROBE (Only if antifreeze protection is present)