A customer is requesting all their machines that are over 50V to have an arc flash label and assessment done. Typically we will do an arc flash assessment of the disconnect the machines are connected to. These are typically 480V 3 phase. I came across a machine that is plugged into a 120VAC outlet and they want a label on the machine. Could a generic label be used for this situation because there is no likelihood of an arc flash to happen? Does a calculation need to be done?

There is no arc flash risk for 120V circuits. So no AF label required.

Mike

Thanks for the quick response. That's what I was thinking. Does it say that in the NFPA 70E anywhere?

I don't recall 120V systems specifically called out in 70E has not being capable of an arc flash. However, research indicates it as such. Also, the tables for PPE selection in 70E do not identify 120V systems.

You could look at this link for more info: https://www.70econsultants.com/arc-flas ... nd-208vac/

Also...get yourself a copy of 70E.

Mike

I feel this is up to the customer. Electrical hazards must be properly identified. While most refer to the labels as "arc flash labels" these nearly always contain both arc flash and electrical shock information. If the facility does not otherwise identify the enclosures voltage or presence of electrical shock hazard, they may be looking for these labels to do so. A very large customer used a modified version of our arc flash labels to identify the voltage and electrical shock hazard information but stated "NO ARC FLASH HAZARD PRESENT".