| Cause | Explanation | |-------|-------------| | | KTY84 or PT100 open circuit. Drive interprets infinite resistance as overtemperature. | | Short circuit | Short across sensor leads = zero resistance, also interpreted as fault. | | Wrong sensor type configured | Parameter p0600 (temperature sensor type) set to “no sensor” but sensor wired, or vice versa. | | Sensor connected to wrong terminals | Example: KTY connected to terminals for PTC thermistor. | | Faulty sensor | Internal damage to the thermistor or RTD. | | EMI interference | Noisy signal lines cause erratic resistance readings. |
He checked the DC link voltage. The capacitors in the line module were humming, charged and ready. But the second motor siemens drive fault code 7902
This fault occurs when the drive detects that the motor is not rotating properly—or is rotating too slowly—despite being given a command to run. | Cause | Explanation | |-------|-------------| | |
Tighten all terminal connections at both the inverter output and the motor terminal box. | | Wrong sensor type configured | Parameter
Before changing parameters, restore the converter to its factory settings to remove any incorrect configurations (using a BOP-2, IOP-2, or Smart Access Module). 2. Enter Quick Commissioning Set the drive to quick commission ( p10 = 1 ). 3. Set Motor Data (Crucial Step)