The KONGSBERG DZ-110/U Transmitter Barrier Unit is designed to

safely provide signal interface and pow er supply to Kongsberg

instrumentation located in hazardous area. The unit connects

intrinsically safe 4-20 mA transmitters.

Principle of operation

The Transmitter Barrier is installed in safe area, designed to

limit the amount of energy that could appear in an electric circuit

that connects to instrumentation located in hazardous area.

The DZ-110/U is a single channel shunt diode safety barrier,

intended for energising a 2-wire, 4-20 mA signal transmitter

installed in hazardous area. A “current mirror” amplifier re

peats the transmitter current into an equal magnitude safe

side current. To prevent leakage through the zener diodes, the

voltage applied to the barrier section is regulated and limited

to a suitable level. Active current limiting is also incorporated to

prevent fuse blow-out during accidental shorting of the transmit

ter circuit.