Solution
This error occurs when a hazardous voltage is detected at the output terminals of the SMU. A voltage that is greater than the maximum voltage limit is considered hazardous. This voltage limit depends on the state of the
Safety Interlock of the device:
- If the Safety Interlock is closed, the voltage limit refers to the maximum voltage of the device.
- If the Safety Interlock is open, the voltage limit is +/- 40 VDC. A hazardous voltage is detected if the terminals exceed +/- 42 V (peak) with a tolerance of +/- 0.4 V.
Note: The status of the
Safety Interlock can be checked with the
Interlock Input Open Property .
This error can be fixed by resetting the device using the
niDCPower Reset Device VI . However, the source of the problem should be addressed to prevent the error from reoccurring.
If resetting the device does not fix the error, the following areas should be checked:
- The voltage limit of the device if the Safety Interlock is open.
- If the voltage limit is set to a greater value than +/- 40 VDC, this error will occur.
- Check the Overvoltage Protection (OVP) limit using the OVP Limit Property and ensure that it is within the allowable range. This property can be written to in LabVIEW if needed.
- Refer to the Using the Safety Interlock topic for the PXIe-4135, PXIe-4136, or PXIe-4137 for further information.
- Ensure that a voltage is not being applied to the Safety Interlock input terminals.
- Ensure that there is no oscillation created when the SMU connects to a DUT.
- The SMU should always be connected to the DUT to avoid overprotection errors.
- If this is not possible, and the SMU must switch between DUTs, ensure that the SMU is always connected with a known voltage.