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USER MANUAL – Release 1.2 of 01/01/2010
Page 115 of 191
Version: 02/03/2010
1= regulates common condenser water inlet probe
2= regulates common condenser water inlet probe and 1 / 2 condenser input
3= regulates common condenser water inlet probe and 3 / 4 condenser input
4= regulates 1 / 2 condenser water outlet probe
5= regulates 3 / 4 condenser water outlet probe
6= regulates on 1 / 2 / 3 / 4 condenser outlet
7= regulates on 1 / 2 / 3 / 4 condenser outlet and common outlet
8= regulates on external air temperature
Par. PA11
= Pump activation set-point in anti-freeze working mode on temperature control probe
Par. PA12
= Pump deactivation differential in anti-freeze working mode on temperature control probe
43. WATER PUMP MAINTENANCE REQUEST FUNCTION
The
PA25 / PA26
parameters are the condenser water pump/condenser support water pump working timer
set.
They establish the number of working hours of the pumps, beyond which a maintenance request is made.
(the timer working threshold value at zero disables the function).
The pump is switched off if:
Unit in ON – OFF remote/stand-by
digital input configured as active condenser water pump circuit breaker.
digital input configured as active condenser water flow switch with manual alarm
(in defrost mode in the periods in which the compressor is in dripping OFF mode, the pump remains
on)
If only one pump is configured, the pump keeps working; if two pumps are configured, there is the
rotation.
44. SWITCH-ON/OFF WORKING WITH PUMP-DOWN
The pump-down working can be based on 3 inputs depending on the configuration of the unit on the basis of
the priority table defined successively.
1. If a dedicated pressure switch is configured, the pump-down basis itself on the same.
2. If a low pressure transducer is configured and both PD02 and PD03 values are different to 0, the
pump-down bases itself on these values
3. If a dedicated low pressure switch is configured, the pump-down basis itself on the same.
4. If none of the conditions 1-3 occur and the pump-down is active, a configuration alarm occurs.
Pump-down on shutdown:
function active when temperature control requests switch-off of the last
compressor (or power step) active in the circuit or following unit switch-off from keyboard or remote.
The
pump-down at shutdown is by-passed in the case of shutdown due to alarm.
Before the effective switch-off of the compressor/step the solenoid valve is closed. This condition (valve
closed with circuit still active) remains until an effective switch-off condition of the last compressor/step takes
place. This condition can be expressed as:
•
Activation of the digital input relative to the low pressure pressure switch of the circuit
•
Activation of the digital input relative to the dedicated pressure switch in the circuit (pump-down
pressure switch)
•
Exceeding (downwards) the threshold set in parameter PD02 by the pressure detected by the low
pressure circuit transducer.
•
Exceeding the maximum duration of the pump-down cycle defined at parameter PD04. In this case a
pump-down alarm on shutdown will be signalled
depending on the parameter settings and the analogue and digital inputs.
Pump-down on start-up:
function active when the temperature control requests start-up of the first
compressor (or power step) of the circuit.
Before starting up the compressor/step, the solenoid valve is opened. This situation (valve open with
compressor off) remains until the compressor/step switches on. This condition can be expressed as:
•
Deactivation of the digital input relative to the circuit LP pressure switch
•
Deactivation of the digital input relative to the dedicated pressure switch in the circuit (pump-down
pressure switch)
