Meter Calibration Requirements

[yesterlectric]

Some safety departments are now requiring that for a meter that you use to verify that a circuit is de-energized, that the meter must have been calibrated within the last 12 months. This is I believe not an OSHA requirement but something that companies have decided to require. NFPA 70 E just requires live – dead – live and I’m sure they have something about inspecting your meter. And I think OSHA requires something similar but actually a little bit less.

Since you don’t need extreme accuracy to tell if a circuit is live, I’m wondering about the effectiveness of a typical calibration check that may be done. Does the standard meter calibration deal with other things besides accuracy? Does it involve any rigorous inspections of the meter or any inspections/tests that might help identify impending failure?

 

[petersonra]

It does prove that the meter functions properly.

Personally, I don't see the benefit of calibrating a meter for most of what meters are used for. usually what we are looking at is a go/no-go type reading. It does not matter much if it reads 110 V or 130 V. If it reads something close it is good enough.

 

[don_resqcapt19]

I see no reason for that, for a meter being used to verify de-energization. You are required to do a live-dead-live test. That verifies the meter is functioning for the actual test.

 

[yesterlectric]

These responses are in line with what I thought.

I wonder though. For high-voltage testers that are on hot sticks there are things like annual testing for the insulation of the hot stick and I believe there also tests for high-voltage tick tracers. It might be that companies that work with this type of equipment have succumbed to thinking there would be a benefit to requiring something similar for a 1000V/600 V class meter.

 

[garbo]

I retired from a large hospital that had a strong safety department that we had to have them sign form for weekly testing of seven fire pumps and turning off a 120 volt circuit breaker but never had us send our meters out for calibration. Several tines a year I would check my AC & DC voltages and Amprobe readings with a coworker meters. I performed up to 30 PM'S a week on drives & starters so my test leads never lasted more then 18 months. So even if you sent out a meter to be calibrated the next day it could provide no voltage reading with a bad test lead. Back in the 1970's we use to send out our Simpson model 260 VOM'S out once a year for calibration and at the same time replaced test leads. In 40 plus years of using digital meters never came across one that appeared to be out of calibration. Still have my dads 65 year old 600 amp clamp meter that you might have to use a screwdriver to get needle to sit at zero. ( for you younger sparkies this is an analog meter ). Still have a couple of analog Amprobes that I purchased 50 years ago.

 

[Ken_S]

If I was a safely officer for a company I would be more concerned about complacency than calibration. I would have regular checks to ensure the electrical staff was following proper procedure