RDZ UMHPI, User Manual

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UMHPI
Industrial inverter air/water heat pumps with axial fans
14
−
The requests of capacity decreasing will be done by selecting among the whole running compressors at the nominal
capacity. The selection will consider the one with higher hours number of operation.
7.4.4 EMERGENCY CONDITIONS
If an alarm is warned by one of the inverters, the compressor corresponding to the faulty inverter cannot startup and the error
code will be displayed, note that, the alarm of any inverter will stop the operation of the whole compressors.
When the serviceman operates on the appliance and decides to make it operating by extruding the compressor related to the
faulty inverter, in order to do that, he must change the value of the parameter
N06 from 0 to 1.
Please see paragraph 11.9 for changing the parameters.
This new setting will affect immediately the operation and will be memorized; the serviceman should restore the previous value
once the fault inverter has been repaired or replaced.
7.4.5 DHW LOGIC CONTROL
The maximum serviceable capacity is used always in case of DHW mode operation (like if the controller regulates the compressors
to run always at 100% capacity).
They are active however the various limitations of the maximum frequency that are related to the envelope and to the limitation
for maximum power consumption.
7.4.6 DEFROST FUNCTION CONTROL
In defrosting cycle, when the time period ( C11 ) has finished at the minimum frequency Pa C18 (according to what is required with
the envelope), the regime of the compressor is set by the value of the parameter C19 . The compressor speed cannot be adjusted.
Anyway the eventual restrictions obtained from the envelope are still valid. Please see paragraph 11.9 for changing the
parameters.
7.4.7 INVERTER COMPRESSOR CONTROL IN COOLING MODE
The management of the compressors depends on the ambient temperature and on the water temperature setpoint.
The regulation is propor integral (PI) with:
ST = regulation temperature sensor
Set cool (G01 ) = setting of cooling setpoint
b01 = cooling regulator proportional band
b05 = compressor control delta cut-off
b07 = integral time
HzMin = Minimum frequency of operation derived from the algorithms of limitation
HzMaxReg = Maximum working frequency of the compressor in cooling mode based on the limitations described in the
previous paragraphs
The following curve shows the adjustment without integral component ( b07 = 0)
During the start-up, the compressor initiates at the minimum speed C12 or C14 (as defined from the envelope) for a given time
period equal to C11 and then changes its speed to C13 for a period equal to C51-C11 .
7.4.8 HEATING FUNCTION CONTROL
The compressors are active in heating mode if the heat pump is enabled
•
H09 = Configuration of the heat pump presence parameter (0 = Heat pump not present; 1 = heat pump is present)
•
ST = regulation temperature sensor
•
Set heat G02 = setting of heating setpoint
•
b02 = compressor regulation band in heat pump mode
•
b05 = compressor control delta cut-off
•
b07 = integral time
•
HzMin = Minimum frequency of operation derived from the algorithms of limitation