Our site is certified to the 100v HBM specification but we now have a customer with a single part that requires 75v HBM. In many instances we can measure voltage directly to insure we do not exceed that requirement. But when it comes to carts, racks and other items we would normally measure these things in ohms with our resistance meter and weights. Is this still an acceptable practice to show we are in compliance and what would our resistance limit be for a 75v HBM component?
I’ll give this a go…
It is important to remember HBM testing is related to human contact with the ESDS item and relies on a known capacitance in-line with the discharge path. CDM removes that capacitance and would be more like direct contact with a grounded conductive item (basically no resistance to ground). There are non industry standard tests that can be completed on voltage generation caused by carts moving around an EPA, but HBM control would rely on the effectiveness of your personnel grounding control via footwear flooring and/or wrist straps. STM 97.2 shows how to capture voltage measurements related to movement using a footwear flooring system. This method could also be used as a reference to show voltage measurements while using wrist straps.
Hope this helps, and I’m happy to continue discussing if I’m not meeting the intent of your question.