Motor Protection; Operation Of Explosion Proof Motors With Type Of Protection "D - Siemens SINAMICS G130 Engineering Manual

Motors
Engineering Information

Motor protection

The motor can be protected against overloading by the I
This prevents operation at excessive motor currents.
More precise motor protection, which also takes into account the influence of the ambient temperature, is possible
using direct temperature detection with KTY84 sensors or PTC thermistors in the motor winding.
To order the KTY84 sensors for motors of type 1LA8/1LA4 and 1LG4/1LG6, motor option A23 must be specified in
the order. The sensors are fitted as standard in 1PH7 and 1PL6 motors.
If PTC thermistors are required, option A11 (for tripping) or A12 (for alarm) must be specified in the order for motors
of type 1LG4/1LG6. With 1LA8/1PQ8 motors, the sensors are fitted as standard.
An evaluation unit for the KTY84 and/or PTC sensors can be connected to the customer terminal block in cabinets
G150 and S150. The connection must be made to terminal –X41 of the Power Module of G130 Chassis.
PT100 temperature sensors (resistance thermometers) for monitoring the motor winding temperature are available as
an alternative for 1LA8 and 1LG4/1LG6 motors. In this case, option A60 (3 x PT100) or A61 (6 x PT100) must be
selected in the motor order.
A separate evaluation unit is available (option L86) for evaluation of the PT100 temperature sensors in the
SINAMICS G150 and S150 cabinets.
With 1MJ flameproof motors, PTB-approved PTC thermistors and tripping devices are absolutely mandatory. These
are available for SINAMCS G150 and S150 cabinets as option L83 (for alarm) and L84 (for shutdown).

Operation of explosion proof motors with type of protection "d"

Siemens 1MJ asynchronous motors can be connected as explosion-proof motors with flameproof enclosure
EEx de IIC both to the mains supply and the converter.
The relevant directives specify that 1MJ motors must be equipped with PTC thermistors.
If 1MJ motors are connected to converters, their maximum permissible torque must be reduced, depending on the
load characteristic, for utilization according to temperature class B, in exactly the same way as 1LA motors with the
same output.
1MJ motors have a terminal box with "increased safety" EEx e II as standard.
For detailed motor data, please refer to catalog D81.1.
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© Siemens AG
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t monitoring function integrated in the SINAMICS firmware.