Question:
Is the bus terminator resistor of the fieldbus function module profibus DP E82ZAFPx activated, when the frequency inverter is switched off and the module is not supplied externally?
Answer:
In case of the profibus DP the terminating resistor of the profibus slave is supplied with voltage. This means that, when the frequency inverter is switched off and the module is not supplied externally, the terminating resistor is not activated anymore, which can lead to problems in the profibus communication, as the fieldbus has an open end.
This means that, when the terminating resistor of the fieldbus function module E82ZAFPx is activated, you should ensure that the module is supplied with 24 V externally for the case that the frequency inverter is disconnected from the mains while the machine is running.
