Can We Use PXIe-2529 Above 150V Rating?

Issue Details

I need to source 150V to a DUT using an SMU for multi-DUT testing, and I plan to use an NI PXIe-2529 switch for the connections. However, with a lead drop voltage of up to 3V, I have concerned that 153V might flow through the PXIe-2529. Since the specifications advise not exceeding 150V, I am worried this could damage the switch.

Solution

The 150 V rating of the PXIe-2529 is a critical safety specification, as NI guarantees safe operation only up to this limit. The PXIe-2529 is not designed with the necessary isolation for voltages exceeding 150 V, and surpassing this limit could increase the risk of exposing users to hazardous voltages. Operating beyond 150 V is outside the product’s specified usage, jeopardizing both user safety and the hardware.

Although the relay contacts in the PXIe-2529 may handle voltages higher than 150 V, the isolation to other circuits is insufficient for such voltages. Because hazardous voltages are involved, any issues could pose a danger to the user and cause hardware damage.

For applications requiring voltages above 150 V, consider using the PXIe-2527, which is rated for up to 300 V. Though the PXIe-2527 shares some design aspects with the PXIe-2529, such as similar terminal block construction and relays, the differences in PCB spacing and isolation particularly in how the PXIe-2527 isolates relay drive circuits from low-voltage controls, make it more suitable for higher voltages.