Fema DCM Series Assembly And Operating Instructions Manual page 44

7. Pressure limiters / Pressure monitors in intrinsically safe control
circuits with open-circuit and short-circuit monitoring (EEx-i)
The pressure monitors corrspond in
all technical data to the Type DCM. In
addition, a resistance combination is
provided in the switching device, which,
together with the isolating amplifier
EX 041, monitors the electric cables bet-
ween isolating amplifier and pressure
monitor for open circuit or short circuit.
In the case of open circuit or short
circuit, the system switches off towards
the safe side. When choosing the type
and when connecting please strictly
distinguish between maximum pressure
and minimum pressure monitoring, as
well as monitoring and limitation
function.
EX-Zone 1 or 2, 21 or 22
red
Exit III Exit II
(according to VDE 0660 part 209)
Ex-free Zone
yellow
green
Exit I
Supply voltage
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