6. Thermostats in Intrinsically Safe Control Circuits (Ex-i)
MU2B-0375GE51 R0616C
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6. Thermostats in Intrinsically
Safe Control Circuits (Ex-i)
Thermostats for intrinsically safe
circuitry (Ex-i) are classified as
"simple electrical devices" according
to Section 5.7 of EN 60079-11.
The terminals and cable glands feature
the light-blue color usual for Ex-i.
Microswitches are equipped with gold-
plated contacts. The switching contact is
single-pole changeover.
The switching difference cannot be
adjusted.
1 2 3
Fig. 12. Wiring diagram
The wiring diagram applies for max.
pressure monitoring.
At rising pressure contact 3-1 opens and
3-2 closes.
Installation only in combination with a
suitable EC-type tested switching
amplifier. Amplifier must be installed
outside the Ex-zone. The wiring diagram
of the switching amplifier and valid
