MAXA i-32V5C MIDI 0121, Руководство пользователя

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Controllo per i-32V5 MIDI
Air/water inverter chillers and heat pumps with axial fans
13.3 DHW CALL FROM DIGITAL INPUT
If DHW operation is enabled and parameter H51 = 28 , is set, as an alternative to using the DHW temperature probe (H17 = 0), the DHW function
can be activated by closing/opening digital input DI7. The unit goes into DHW mode when the contact closes and exits DHW production when
the contact opens.
The polarity of digital input ID7 can be inverted by setting H75 = 64.
NOTE: this function is not activated if the double set-point management is used.
This function is recommended when using two or more heat pumps in cascade, hydronically connected to the same domestic hot water storage
tank. In this case, the activation of the domestic hot water function can be set on the first machine via the DHW probe of the tank, while the
other machines are automatically enabled thanks to the consent given by the digital input.
CAUTION:The SAN setpoint of the heat pump is not considered; management of this setpoint is delegated to the designer,
who must take into account the DHW protection and the configuration of the entire system.
13.4 SYSTEM WATER REMOTE PROBE
In some system solutions (e.g.: heat pump in parallel with the boiler on the same hydronic circuit and exclusion diverter valve) it may be neces-
sary to enable a temperature probe of the system so that the on-board control can process the management correctly. The system remote probe
is activated by setting parameter
H18 = 41
.
The system remote probe thermoregulates the heat pump only during the compressor start-up phase, the switch-off is managed by the probe
on the heat pump delivery.
In heating mode, the call is active if the following conditions are verified:
• Flow probe temperature < Hea – 2°C ;
• Temperature of the system remote probe <
Hea – b22
(default b22 = 5,0°C).
In cooling mode the call is active if the following conditions occur
• Flow probe temperature > Coo + 2°C ;
• Temperature of the system remote probe > Coo + b22 (default b22 = 5,0°C).
14. DEFROSTING CYCLE
The defrost cycle is a function active only in heat pump mode and is used to prevent the formation of ice on the surface of the finned coil. The
formation of ice on the evaporator, which occurs more frequently at very low external ambient temperatures, not only considerably reduces the
thermodynamic efficiency of the machine, but also leads to the risk of damage to the machine itself.
NOTE: if the remote off command is activated during defrosting, the unit finishes defrosting and then switches to OFF mode.
15. DOUBLE SET-POINT
This function introduces a second working set-point on the plant side, both in cooling and heating mode.
The user terminal board allows a consent to be connected to switch from the first to the second set-point and configured at digital input DI9 with
parameter
H53 = 26
. The valve,on the other hand, is connected in the terminal board to digital output DO7 and is configured via parameter
H85
.
Parameter VALUE Function
H53
26 Call for second set-point
H85
25 3-way valve for radiant panels
H129
0 Function disabled
1 Function configured but not active
2 Enabled only in cooling mode
3 Enabled only in heating mode
4 Enabled in cooling and heating mode
16. MINIMUM HZ FUNCTIONS
Configuring parameter L02=1 and L03≠0 reduces the nominal operating Hz of the compressor.