Siemens SINAMICS G150 Operating Instructions Manual page 152

Electrical installation
4.10 Other connections
NOTICE
Damage to the motor in the event of incorrectly connected KTY temperature sensor
If a KTY temperature sensor is connected with incorrect polarity, it is not possible to detect
when the motor overheats. Overheating can cause damage to the motor.
• Connect a KTY temperature sensor with the correct polarity.
NOTICE
Overheating of the motor through jumpering the temperature sensor connections
Jumpering of the temperature sensor connections "+Temp" and "- Temp" results in
incorrect measured results. Damage to the motor can result if the overheating is not
detected.
• When using several temperature sensors, separately connect the individual sensors to
NOTICE
Device failure as a result of unshielded or incorrectly routed cables to temperature sensors
Unshielded or incorrectly routed cables to temperature sensors can result in interference
being coupled into the signal processing electronics from the power side. This can result in
significant disturbance of all signals (fault messages) up to failure of individual components
(destruction of the devices).
• Only use shielded cables as temperature sensor cables.
• If temperature sensor cables are routed together with the motor cable, use separately
• Connect the cable shield to ground potential through a large surface area.
• Recommendation: Use suitable Motion Connect cables.
Note
Incorrect temperature measured values as a result of cables with an excessively high
resistance
An excessively long cable length or an excessively small cable cross-section can falsify the
temperature measurement (for a PT100, 10 Ω cable resistance can falsify the measurement
result by 10%). As a consequence, excessively high measured values are output, which
could lead to the motor being unnecessarily tripped prematurely.
• Use only cable lengths ≤ 300 m.
• For cable lengths >100 m, use cables with a cross-section of ≥1 mm
152
"+Temp" and "-Temp".
shielded cables twisted in pairs.
.
2
Converter cabinet units
Operating Instructions, 07/2016, A5E03347396A