Device description
3ZX1012-0RB12-1AA1
11
En
glis
h
Limited touch protection
Degree of protection in conformity with IEC 60529:
IP 20 for devices 70 mm
IP 00 for devices > 70 mm
Shock-proof in conformity with DIN VDE 0106, Part
100.
Installation and maintenance by technical personnel
only. Follow the operating instruction!
1
Device description
The 3RB12 electronic overload relay protects electrical
equipment, such as three-phase AC motors and trans-
formers, with three different protection mechanisms.
Overload
protection
The 3RB12 compares the motor current actually
flowing with the set current and evaluates the values
in a microprocessor.
Thermistor
protection
PTC thermistors in the motor windings sense the motor
temperature. If the thermistor responds, the relay trips.
Earth-fault
protection
Versions with internal earth-fault detection are suitable
for service in three-wire systems.
Versions with earth-fault detection by means of an
external summation current transformer are suitable
for service in three-wire and four-wire systems.
WARNING
HAZARDOUS VOLTAGE
CAN CAUSE ELECTRICAL SHOCK
AND BURNS.
DISCONNECT POWER BEFORE PROCEEDING
WITH ANY WORK ON THIS EQUIPMENT.