Carel MPXone ACS00CB000010, Руководство пользователя

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Fig.5.a
MPXone, inside the showcase or cold room, can use temperature probes to measure:
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the air outlet (off) temperature (at the evaporator outlet);
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the defrost temperature (in contact with the coldest point of the evaporator);
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the air return (on) temperature (at the evaporator inlet).
The default configuration for assigning the control probes is as follows:
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S1 = Air off probe (Sm);
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S2 = Defrost probe (Sd);
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S3 = Air on probe (Sr).
The default configuration also involves these three probes being standard CAREL NTC. However, other
types of probes can be connected by setting parameter /P1. On MPXone the default settings can be
changed to choose the function associated with any of the probes connected. There are also cases where
the characteristics of the applications require different settings.
Share control status
This function is used to satisfy the needs of cold rooms or showcases with multiple evaporators, where the
Slaves are essentially used as expansions for the management of different electronic valves. This function
shares the Master control status across the LAN (RS485). In this way, the Master determines the control
status, and each Slave operates as a consequence, without consider the parameters set locally. This means
Slave controllers can be used without the air off and on probes. If the Slave controller is not accessible
from the Master, “duty setting” operating mode must be activated, setting the corresponding parameter
c4 >0.
Activation: to activate sharing of the control status, set /FA = 0 and /Fc = 0 on the MPXone Slave
controllers.
Note:
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the configuration /FA = 0 and /Fc = 0 on a Master controller causes the alarm ‘rE’ (control probe
alarm)
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if the Slave controller is not accessible from the Master, alarm ‘MA’ is displayed (Communication
error with the Master - only on the Slave)
The function manages the control status (activation and deactivation of the cooling request) on the Slave
controllers from the Master via the LAN (RS485). This means that only the Master parameters (set point,
differential, night-time set point variation, control offset in the event of probe error) affect the control
algorithm. The value of the same parameters on the Slaves has absolutely no influence. If the Slave
controller is not accessible from the Master (the user interface shows alarm ‘MA’), “duty setting” mode is
activated based on the local setting of parameter c4, and the corresponding management (duty setting
starts in the status found prior to the instant it is activated, i.e. it starts with compressor on if this was on,
and with compressor off if it was off).
Notes:
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if the Master controller enters duty setting mode, the related Slave controllers follow as regards
the compressor management times and the user interface does not show the icon flashing when
the compressor is off, due to the fact that they ignore the Master control mode. On the other hand,
if the Slaves enter duty setting mode due to lack of communication with the Master; in this case
they manage the user interface correctly;
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activation of the continuous cycle on the Master means all the dependent Slaves observe the
compressor management times on the Master (parameter cc on the Master only will take effect,
while the settings on the Slaves will be ignored). This operating mode is only highlighted on the
ENG
0300086EN rel. 1.0 – 04.09.2018
5. Functions | 39