Description
2.5 Design
Naturally cooled 1FW6 built-in torque motors
Operating Instructions, 07/2017, 6SN1197-0AF02-0BP2
39
Temp-S
All motors are equipped with the following temperature monitoring circuit to protect the motor
winding against thermal overload:
●
1 x PTC 130 °C temperature sensor per phase winding U, V and W, i.e. response
threshold at 130 °C
The three PTC temperature sensors of this temperature monitoring circuit are connected in
series to create a PTC triplet.
Figure 2-5
PTC triplet
To protect the power connection at the enclosure against thermal overload, an additional
PTC 80 °C is connected in series with the PTC 130 °C triplet.
Every phase winding is monitored so that also uneven currents - and therefore the
associated different thermal loads of the individual phase windings - are detected. For the
following motion and/or operating states, the individual phase windings have different
thermal loads, while the motor simultaneously outputs a torque:
●
At standstill (holding)
●
When rotating very slowly
●
Oscillation through a very small angle
Note
Shutdown time
If Temp-S responds, and its response threshold is not undershot again in the meantime, then
the drive system must shut down (de-energize) the motor within 2 seconds. This prevents
the motor windings from becoming inadmissibly hot.
