Description of the circuit if the criterion "intrinsically safe" does not apply
The following 2 circuits exist:
Circuit 1 | Circuit 2 |
|---|---|
|
|
[1] | Line contactor | [4] | PLC |
[2] | Braking resistor | [5] | Inverter |
[3] | Internal temperature switch or overload relay |
Circuit 1
The signal contact is only evaluated in the PLC.
If the internal temperature switch responds, note the following:
- The PLC must disconnect the power supply.
- There is no direct response in the inverter.
With circuit 1, it is possible that the PLC finishes the current travel cycle although the thermal circuit breaker has tripped. Only then is the power supply disconnected. In this case, the residual braking energy Wres = PBR_nom × 20 s must not be exceeded.
Circuit 2
The signal contact directly affects the line contactor.
If the internal temperature switch responds, note the following:
- A response by the PLC is not required.
- There is no direct response in the inverter.
