GFA SI 80.12-55,00 Ex, Installation Instructions Manual

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15
Protection against overload
Motor protection switch / motor protection relay mains operation
The "Ex" motor must be protected against overload by means of a motor protection switch or
a motor protection relay. Only use motor protection relays with manual reset. Short-circuit
protection is also required. Excess current must be set on the basis of the I
A
/ I
N
ratio.
PTC resistor signal mains operation
The motor is equipped with installed temperature sensors (PTC) which can be used as
overload protection. This protection class is approved as the sole protection against overload
for flameproof motors "d"; it must be equipped with a separate evaluation unit. The evaluation
unit measures the temperature of the motor coil and deactivates the motor as soon as the
preset temperature is exceeded. This safety device can only be reset by hand. Short-circuit
protection is also required.
PTC resistor signal frequency inverter operation
Evaluation is similar to that in mains operation. The motors have an additional rating plate.
The features on the additional rating plate must be checked before initial operation of the
motor. The connecting cable of the temperature sensors (PTC) must be routed separately to
the motor cable.
Frequency inverter operation!

Shielded motor cables must be used.

Shielded cables require separate cable glands.

The brake requires a separate supply line.