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The maximal length of the cable from the I/O board to the sensor should not be longer
than a few meters.
AC Outputs
AC outputs are activated by 24V AC.
Each AC output is connected to the I/O board by 2 wires that may be interchanged.
Several AC outputs may share one wire as common; this wire will be connected to any
of the terminals on the outputs terminal block marked by the letter “C”. The thickness of
the common wire is dictated by the number of solenoids to be activated simultaneously
and the power rating of the solenoids.
Commons of separate I/O boards cannot be interconnected.
The length of the wires from the I/O board to the AC device to be activated may be
hundreds of meters long, but the required wire thickness grows with the distance.
An output remains activated as long as it is energized.
Solenoids of normally open valves and normally closed valves will be wired the same
way to the terminal board but will differ in the connection of the command tubes and
sometimes will differ in their physical structure.
Measuring the voltage of an AC output while it has no load connected to it, can be
misleading, it will show 24v AC even when the output is not activated.
DC Pulse Latching Outputs
DC latching outputs are activated by short pulses of energy and they are kept in their
last position by magnetic means, that’s why they are energy saving.
Each DC output is connected to the I/O board by 2 wires – red and black of which the
polarity is important. The terminal block of the outputs contains two terminals per each
output; one terminal is marked by the ordinal number of the particular output and the
other by the letter “C”. For normally open valves, the black wire will be connected to the
terminal marked “C” and the red wire to the terminal marked by the ordinal number. For
The outputs’
common is
marked by “C”
Inputs terminal
block
Outputs
terminal
blocks
Inputs terminal
block
Outputs
terminal
block
The outputs’
common is
marked by “C”
The inputs’
common is
marked by “G”
The inputs’
common is
marked by “G”