Main breaker popping at 10A

[Korvessa]

Originally Posted by Cadence

I doubt you meter isn't up to the task. Replace the breaker. If you had a bad connection to make a 30A break trip at around 10A you would have already burnt to the waterline.

That's quite reassuring..... I think.

It is a point well taken though and very helpful advice. To continue the troubleshooting, I do have a voltage meter built into the system and it never drops. In addition, I've encountered this problem at 5 different marinas recently so the issue isn't the voltage supply.

I do have a spare shore power cord I could swap out, as one poster mentioned they burn up when heaters are used. I'm not sure how or why that happens, but I have observed blackening at the shore side end of cables before.

I'll definitely replace the breaker as it sounds like a likely culprit.

[ojwoody]

Get yourself an AMP Meeter. Only way to truly know what is going on.
send me the results and I can tell you where the problem is. They are super easy to use.

[Cadence]

Check the voltage to the breaker. If it doesn't drop under load your shore power cord isn't the problem. If it does look at it. Your meter not being good enough is not a problem. Buying a Fluke or an clamp on ammeter is totally unnecessary. I'm still betting on a bad breaker. The only other thing I can see is you have a current draw you aren't considering, a reefer or something?

[Korvessa]

Originally Posted by ojwoody

Get yourself an AMP Meeter. Only way to truly know what is going on.
send me the results and I can tell you where the problem is. They are super easy to use.

Seems like a piece of kit I need. I've ordered one and it should arrive tomorrow.

Stay tuned!

Korvessa

[hzcruiser]

Originally Posted by Korvessa

Seems like a piece of kit I need. I've ordered one and it should arrive tomorrow.

Stay tuned!

Korvessa

Which one did you get?

[Korvessa]

Originally Posted by hzcruiser

Which one did you get?

While I know Fluke is the best, it's a lot of coin. If my cheap unit doesn't do the job, it'll at least be a backup if I have to buy a better one.

Here's what I chose. It was highly rated on Amazon.

[hzcruiser]

Originally Posted by Korvessa

While I know Fluke is the best, it's a lot of coin. If my cheap unit doesn't do the job, it'll at least be a backup if I have to buy a better one.

Here's what I chose. It was highly rated on Amazon.

That looks decent enough for your specific purpose. However, there are two "pitfalls for young players" with them.

First, check out the first cu review:

I purchased this clamp meter primarily to measure current/amps on 120 volt appliances, heaters, etc. To do this with ANY clamp meter, you MUST separate the hot and neutral conductors or they will cancel each other out and give a zero amp reading.


To cover that, I fabricated my own little adapter that has the three leads separated so I can measure AC current with the clamp.

Secondly: In the future, you might be interested in measuring DC currents to/from your batteries as well, and this is something a lot of the clamp meters (even from Fluke) including yours-to-be, can't do, unless it's explicitly stated.

[smac999]

yes I did mention to get one that will do both ac and dc. so you can trouble shoot battery issues as well. oh well.

[Redpcx]

I worked in a related field.
Breakers do not employ a "controlled explosion". They will trip at the specified value, in the specified time for many trips.
Some breakers are rated for use as a switch and can be turned on an off daily. Most are NOT rated for use as a switch.
However, breakers often go bad.
Moisture is bad for the metal parts, slight heat is bad for the insulating parts. High heat is bad for the steel parts.

A 30 amp breaker that tripped at the 13 amps your heater was running at is now bad. Before you even open the panel, have a new breaker on hand.
Replace the breaker.
It will cost far more than the breaker is worth to properly test it.
Replace the breaker. Even if you find the heat you felt was from wiring, the breaker has been ruined by heat. Replace the breaker.

After you replace the breaker, diagnose other problems if the trip persists.

Breakers hold at their rating, and trip above the rating, the higher the current, the faster they trip.

[Terra Nova]

Originally Posted by Korvessa

...I've encountered this problem at 5 different marinas recently...

"Get yourself an AMP Meeter"

Originally Posted by Korvessa

Seems like a piece of kit I need. I've ordered one and it should arrive tomorrow...

You should have just replaced the bad breaker already.

[Cadence]

Originally Posted by Terra Nova

"Get yourself an AMP Meeter"



You should have just replaced the bad breaker already.

Buy a breaker for a few bucks? Hell no, buy a Fluke and Amprobe you don't know how to use. Makes sense to me.

[Boatyarddog]

Originally Posted by Cadence

Buy a breaker for a few bucks? Hell no, buy a Fluke and Amprobe you don't know how to use. Makes sense to me.

Having spares around is always a good idea, for any cruiser/boater.
Easy diagnosis just swap it out, simplest is best.will save lots of time Head Scratching.
Then get more complicated, if your not comfortable doing that, ask yer neighbors maybe someone will help, boaters love to help.
Cheers,
SV Cloud Duster