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condensation

condensation

condensation

(OP)
I have a pond aerator with a submersible connector sealed at both ends and a clamp/o-ring seal around the middle.  All seals seem fine but the GFI will soon kick out.  I assume this is due to condensation in the connector compartment.  There is a small amount of water present.  How do I solve this problem?  Thanks, joebems

RE: condensation

You have a leak.. Condensation does not come into play in sealed connectors.

You need to find the leak and fix it.

OR! Your line has too much capacitive leakage and that is tripping you GFI.

How long is the cable.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: condensation

(OP)
The cord is about 100 feet long.  But there is a small amount of water inside the connector.  Thanks for info.

RE: condensation

That's a leak. Gotta fix it.

The amount of moist air contained inside a connector, if condensed, won't be enough to leave detectable water in it.

Make sure you have a little something on the O-ring.  Like a little Vaseline or something compatible.  This can help with the sealing.

Good luck.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: condensation

Keith
You said
OR! Your line has too much capacitive leakage and that is tripping you GFI.

Are you referring to the 120 V 20 amp GFCI or are you referring to the industrial type GFIs say for 3 phase?

Tell me more about the capacitive leakage and how or if it can screw me up on 120 volt units.  Can you refer me to a referance preferably one that does not get all involved with high level calculus??

The basics of capacitance in power circuitry I have learned and seen where you have lots of conductors close together ie capacitive coupling.  BUT just because I have seen it does not mean I fully understand it.

Dan Bentler

RE: condensation


Simple really..




Oh, you wanted the simpler version!

Yes certainly you can be screwed up with 120VAC leakage and GFI breakers.

Current passes in other ways then just directly conducted thru metal wire.  With a transformer, power is conferred without a direct connection.  Same thing happens when you have a conductor passing very closely to another conductor.  You can have a little power transferred because of the capacitance.  With the correct situation you can get enough of this capacitive "leakage" to actually trip GFIs.  

You can get a heck of a tingle out this leakage.

I had a refrigerator that would jolt the hell outta us if we touched it an anything grounded at the same time.  It is common with motor like devices because they can have a large amount of wire running near metal.  In a refrigerator all those windings in a metal case.

You can have that problem with a long cable with a ground in it.  You may have some coupling to the ground from the power conductors.  This conducted power is frowned upon by the GFI as it is seen as a fault.

With capacitive systems in general you may have a GFI problem because the inrush or non-symmetrical discharge of the device's energy during turn on or off can cause a brief imbalance that trips the GFIs.

A book.. Dang sorry.  It is more like just the rules of a capacitor. Two conductors separated by distance and having areas.  The transmitted(leaked) current is then a function of the voltage and the frequency.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: condensation

Keith

Who the heck was Levi Civita.
Anyway thanks for the info

Dan

RE: condensation

Keith,
  If you capacitive leakage how do you correct that?

2571

RE: condensation

The short answer... Reduce the capacitance.

This can mean using a different power cord.  When using a cable for communications the capacitance of the cable is very important because the cable's capacitance is essentially shorting the higher frequency components out of the data.  Squarewaves begin looking like blobs.  So the capacitance per foot is always listed by the maker since it is very important to the user.

On power cable it isn't so important so it might be harder to dig up the values.   On some things it means they are failing anyway and should be replaced. 2571 do you have a specific case you're asking about?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: condensation

Conductor insulation starting with an 'X', such as XHHW, will have lower leakage than insulation starting with an 'R' or a 'T' such as RHW or THWN.  There comes a point that the only solution is a higher setting on the ground fault trip.  If you are using a 5mA device, could you use a 30mA device and meet the applicable codes?  If so, you will have far less problem with leakage.  The Eaton/Cutler-Hammer "Earth Leakage" breaker line is broadest line of low current adjustable trip ground fault devices I'm aware of.

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