MAXA i-32V5C MIDI 0121, Manual

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Controllo per i-32V5 MIDI
Air/water inverter chillers and heat pumps with axial fans
14
PROPORTIONAL REGULATION
Δ T
[°C]
Speed
[%]
P07
P08
P06/P09
P10
In practice, in cooling mode, if the temperature difference between the inlet and outlet is greater than P09 + P10, the circulator runs at maximum
speed, but if the difference is less than P09 - 0.2°C, it runs at minimum speed; in the remaining cases, the pump modulates the speed propor-
tionally. In heating mode, the same considerations apply, replacing parameter P06 with parameter P09.
In sanitary production the circulator always runs at maximum speed.
8.6 SYSTEM VENTING
The control allows the use of a manual system venting function with the circulator at maximum speed.
To enable the function the operations to follow are:
• Set unit to OFF
• Access with maintenance privilege PRG -> PSS -> PRG -> (enter installer password) -> PRG
• Press UP and DOWN simultaneously for 3 seconds.
It is possible to exit the system venting cycle manually by pressing the MODE/ESC button,or by pressing UP and DOWN keys simultaneously for
3 seconds.
CAUTION: during this function the flow switch alarm is disabled, the maintenance technician must guarantee that there is
water inside the system.
9. COMPRESSOR ON/OFF LOGIC
The restart of compressors is in operation of a set point refered to the inlet and outlet water temperature. It is based on calculation of ∆T,set that
is the difference between outlet and inlet water temperatures, detected while the compressor for thermoregulation is turning off.
9.1 REGULATION IN COOLING MODE
• Tw,out,set = setpoint in cooling mode
• ∆T,set = Tw,out,set – Tw,in,set
• b05 = compressor delta cut-off set = 0,2°C (default)
•
b25
= delta cut-on regolazione compressor set = 2°C
RPM
Tw,out (outlet water temp.)
Tw,out,set
HzMaxReg
OFF
HzMin
b05
∆T,s et + b25