GFCIs trip when they detect current leakage - usually to ground. They do not sense overcurrent. It's not "too much current" that trips a GFCI, but rather, "current going to the wrong place". For this reason, they are typically associated with wet/damp locations, as the presence of water tends to greatly increase the likelihood of current leakage.

So, let's see here, you've got an object where electricity goes in one end, and water in the other, and you're tripping a GFCI.

I'd say the GFCI is correct - there's some leakage current somewhere. Whether or not this is cause for concern, I can't say. There may be a risk of shock. It is not a fire issue.

I have read references to motors causing nuisance tripping of GFCIs but have never personally observed it.

Is it possible that water is getting to some electrical part or another?

Thanks Pharkus for the quick reply. The point about the current is a good one. I have had this setup without a problem for 3 years and to the best of my knowledge nothing has changed. I will take a look to see if water may be getting where is should not be. I will also try to swap this with a spare pump I have to see if this makes a difference. I will let you know how I make out.

Thanks again,
Tracy

The leakage current for a GFCI to trip is around 5 mA, 0.005 Amps.

Condensation in a box is well known to cause nuisance tripping.

Unless the sump pump specifically requires GFCI protection, I would not use it, especially if the basement will flood if the pump shuts down.

While water and electricity are a bad combination, a flooded basement is also a real problem.

I usually use hard wired sump pumps top eliminate the GFCI issue (no receptacle).

Thanks Brickeyee,

I actually have been running the sump on a non-GFCI circuit for the last week with no problems.I did plug in a de-humidifier into the GFCI as well yesterday and it has also been running fine. The circuit that the sump is running on now only handles 4 basement lights. Do you think it is OK to leave it this way or should I take out the GFCI and hard wire as you suggested?

Thanks,
Tracy

"Do you think it is OK to leave it this way or should I take out the GFCI and hard wire as you suggested?"

How much damage if the circuit trips or the pump gets unplugged?

The quality and reliability of sump pump installations depends directly on the amount of damage that may occur.