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Re: Power line 1 showing zero on the voltmeter

Posted: March 23rd, 2017, 3:05 pm
by jcoll
You learn something new every day! I know I did every time I got a new boat. It'll take about a year to really get to know it if you're like me - but I'm a slow learner LOL. I guess the other lesson here is you can't run to many things at one time. Watch you ammeter on the panel as you use power. There's 30 amps to work with and you might reach that with just a toaster and a coffee maker running at the same time. Good luck with the new boat. Hope you have lots good times.

Re: Power line 1 showing zero on the voltmeter

Posted: March 24th, 2017, 12:42 am
by tomschauer
A big draw is your water heater. If it is heating while making toast and coffee, or using the stove or oven, POP goes the breaker. I always turn off the water heater breaker when the wife is cooking. Usually no problems then.

Re: Power line 1 showing zero on the voltmeter

Posted: March 24th, 2017, 7:19 am
by Viper
Power management is key so you don't stress the circuit and cause hardware issues over time. The breaker is an over-current protection device. If it tripped, there was either too high a load for the circuit or there is a problem with the circuit's wiring or hardware. Unless there was a dead short, the cause is usually due to running too many things at once. When you do that, you draw more through the circuit than it was designed for. This causes heat which starts to affect contact areas. Over time, the more compromised these areas become, the more heat is generated even with sub 30 amp loads.

Unfortunately the shore power plugs we typically use aren't the best. There are better ones that you can upgrade to https://smartplug.com/ but you're still stuck with the traditional design at the marina's post. I'd take a look at all your external plug contacts from and including the shore power post, your Y cord, both cords, and inlets. If any contacts show signs of having overheated such as a discolouration where each contact goes through the housing or melting plastic, replacement is required. Don't underestimate the damage this can cause if it runs away. We tend to think that the breaker will trip when there's a problem....that's not always the case and the result can be catastrophic.

Re: Power line 1 showing zero on the voltmeter

Posted: March 24th, 2017, 11:05 pm
by Lyndon670
+1

The only time I can run everything and not trip out is when my genny is running. At the dock on the post, I have to practise the power management that has been discussed here. Its especially problematic with summer in full pop with AC units running, hot water tank on, and trying to heat up something in the micro.

First world problems!

Re: Power line 1 showing zero on the voltmeter

Posted: March 25th, 2017, 11:08 am
by km1125
I've often thought about putting in a relay on the line to the water heater... with a current sense on the galley plug. When the galley is drawing power, it would switch off the water heater. I don't know if you would EVER notice a lack of hot water doing it this way.

Won't solve the problem of running the microwave and coffee pot at the same time (which are on the same 15A circuit) but will stop the 30A breaker from ever popping.

Re: Power line 1 showing zero on the voltmeter

Posted: March 26th, 2017, 10:39 am
by AaHubb
I found a partial solution to the coffee vs. hot water problem. I pulled out the original GE coffee maker and replaced it with an insulated carafe style coffee pot. Now I can turn off the coffee pot once the coffee is made and still have hot coffee all morning. I get my hot coffee and the wife gets her hot shower... win win!
.. Aaron

Re: Power line 1 showing zero on the voltmeter

Posted: March 26th, 2017, 10:51 pm
by Viper
AaHubb wrote:Source of the post ....insulated carafe style coffee pot.....

That's the kind we use on our boat Aaron. Works great.

Re: Power line 1 showing zero on the voltmeter

Posted: September 27th, 2019, 4:19 am
by peter.dein
Hi

Re. 1995 Carver 370 with twin Cummins diesels -

After a successful engine start, I’ve noticed no alternator charge with the volt gauges sitting on 10v. Normally they display 13-14v. I shut down and then attempted to restart but there was insufficient battery grunt to crank.

My question - Is there an alternator fuse which may have tripped (I can’t find one), OR is it likely to be a sudden alternator failure.

Any advice would be kindly appreciated.

Possible relevance - I have large solar panels professionally installed which keep a healthy battery condition whilst idle on my mooring, however I think the alternator issue is separate?

Cheers
Peter

Re: Power line 1 showing zero on the voltmeter

Posted: September 27th, 2019, 8:16 pm
by buster53
Peter, you might want to start a new thread instead of piggy-backing on one that's different from your problem.

Re: Power line 1 showing zero on the voltmeter

Posted: September 28th, 2019, 8:27 pm
by Helmsman
Viper wrote:Source of the post Power management is key so you don't stress the circuit and cause hardware issues over time. The breaker is an over-current protection device. If it tripped, there was either too high a load for the circuit or there is a problem with the circuit's wiring or hardware. Unless there was a dead short, the cause is usually due to running too many things at once. When you do that, you draw more through the circuit than it was designed for. This causes heat which starts to affect contact areas. Over time, the more compromised these areas become, the more heat is generated even with sub 30 amp loads.

Unfortunately the shore power plugs we typically use aren't the best. There are better ones that you can upgrade to https://smartplug.com/ but you're still stuck with the traditional design at the marina's post. I'd take a look at all your external plug contacts from and including the shore power post, your Y cord, both cords, and inlets. If any contacts show signs of having overheated such as a discolouration where each contact goes through the housing or melting plastic, replacement is required. Don't underestimate the damage this can cause if it runs away. We tend to think that the breaker will trip when there's a problem....that's not always the case and the result can be catastrophic.


Viper, I actually ran into that. This summer I had an issue with a pedestal in downtown Chattanooga. The real issue was the inverter batteries charging, the microwave being used, and AC’s on. We popped breakers. When I looked at the cords they were both “burn marked” on the pedestal side. Threw them away, bought new, and am now committed to power management.

Thanks for the tip.