Voltage Cutoff for Required Enclosure Grounding

[redtail_MH]

Where in the NEC does it set the voltage cutoff for enclosure grounding requirements? What I'm interested in is how to handle the enclosure grounding for 24Vdc instruments. Do these low voltage dc circuits require EGCs just like 120Vac circuits?

 

[infinity]

Look at part VIII of article 250. Starts with 250.160.

 

[redtail_MH]

I see where it addresses system grounding, but I'm concerned with the EGC requirements.

 

[tom baker]

50 volts is typically the limit. See 250.20

 

[redtail_MH]

That appears to be system grounding requirements for AC. It still doesn't address the EGC.

 

[tom baker]

OSHA uses 30 volts for the threshold of shock hazard