Slow GFCI/AFCI trip time

[R Jones]

My coworker and I were just chatting about this weird issue with a new subpanel I installed.
I put in 6 new GFCI/AFCI CH breakers. When I test them with my plug tester's GFCI button, I have to hold the button down for almost a full second before the breaker actually trips!
They all do this! They trip instantly when I use the test button on the breaker itself, but the plug tester test is super delayed.
This can't be normal, right? Is it possible that all six brand new breakers are defective, or could there be some crazy wiring issue causing the lag? What's your take?

 

[Alan]

That’s a good observation, especially since all six breakers are behaving the same way. The difference between the breaker test button and a plug tester tends to raise eyebrows for a lot of people.

Have you seen this behavior on other recent installs, or is this the first time it really stood out?

 

[Carrot_]

Check the resistance of your plug tester. Most cheap testers only bleed off about 6mA to 9mA of current to trip the GFCI
if your subpanel is a long distance from the main bond or if there is any slight resistance in the ground path, it might be right on the threshold of what the breaker considers a trip level fault, causing that weird one second delay while the current stabilizes

 

[PGB1]

I gave up on the plug-in cube type long ago. There's too much variability. I found myself with a couple that had several second trip delay and a couple with instant- on the same circuits.

And, who knows what mA they are really using?

Also avoid no-brand or house brand. A co-worker showed off his brand new eBay $2.00 tester. He unpackaged it, plugged it in, pushed the button and the device exploded in his (thankfully gloved) hand. For the record, the breaker didn't trip!

If funds allow, a good GFCI analyzer would be great to have. Extech makes a nice one (Model CT70). I carry at work a less expensive one from Ideal with adjustable trip thresholds. That one is handy and accurate, but limited to 120 volt circuits. It's good if the device can be calibrated by a NIST certified service agency annually. (All meters benefit, actually)

You can also get testers and analyzers which will perform multiple functions- such as AFCi testing and earth resistance.

You can buy testers with a NEMA 5-15C tail built in or with alligator clamps for test leads, wires or a pigtail with a cord cap. Or make your own suicides if the tester has only a cord cap.