INNOV@-pCO1-IOM-0907-E
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To start the compressor again, the user has to rearm the alarm manually by pushing the display Alarm
button, provided that the pressure switch has rearmed energising the digital input. After the compressor has
turned off, timing is enabled; for this reason, after alarm rearming, the compressor could not immediately turn
on again.
GENERIC ALARM
Alarm including all compressor safety devices in a single digital input, used on two-compressor small boards.
This alarm goes off immediately when opening the digital input and locks the compressor. To start the
compressor again, the user has to rearm the alarm manually by pushing the display Alarm button, provided
that the digital input has been energised. After the compressor has turned off, timing is enabled; for this
reason, after alarm rearming, the compressor could not immediately turn on again.
2.8 Heaters
The heaters are managed as simple ON-OFF loads. Normally up to 2 heaters with the same power can be
managed, connected to the 2 outputs.
“Binary management” allows the use of three heating steps with just tw
o outputs and 2 loads with different
power values:
The outputs with binary logic behave as follows:
2 DIFFERENT LOADS
STEP 1
Heat.1 = On / Heat.2 = Off
STEP 2
Heat.1 = Off / Heat.2 = On
STEP 3
Heat.1 = On / Heat.2 = On
The outputs are activated with a slight delay from one to the other, to avoid simultaneous peaks.
2.8.1 Heater alarms
Each heater is provided with a digital input to be connected with a compressor overload or differential for
signalling any failure.
Immediate alarm originated when the digital input switches from closed to open; the heater is immediately
disabled. To enable the heaters again, the user has to rearm the alarm manually by pushing the display
Alarm button, provided that the compressor overload or the differential have rearmed energising the digital
input.
2.9 Modulating valves
2.9.1 Three-position valves
Valves with three electrical contacts (besides supply): shared, opening and closing.
Based on the relays enabling time, the valves opening range varies from 0% to 100% taking an
opening
/closing time defined as “running time”
(time taken to open or close completely; it is a valves rating).
The relays must never be enabled simultaneously, thus the valve open, close or keep still.
The valves opening range is calculated based on the proportion between temperature differential and
running time. When ambient temperature corresponds to the set point, the valves keep closed; the more
temperature is offset compared to the set point the more the valves are opened, until they open completely
when temperature is equal or higher than set point + / - differential.
During operation, the valves are frequently subject to partial opening and closing; the program can recognise
the valves opening range at any time by adding up and subtracting all partial times executed from board
start-up.