Electrical help

JerryG · 02-21-2020, 12:15 PM

I recently came home from an extended stay. When I arrived I started my generator until I could string out my Shore cord. I have an 05 Journey 39k. I turned off my generator and plugged in my cord and went to bed. The next morning I went out to my coach to unload and discovered I had no lights and the fridge was defrosting. I checked all my breakers they were good still no power. I got out the multimeter and checked electrical appliances on 120 they were powered up. I checked my swithes at the box all good. I was reading about a similar situation on a similar coach as mine maybe a year or 2 newer. This person found a 300 amp fuse blown or so he stated. Does anyone reading this know anything about a fuse like this in my coach. If not does it sound like maybe my converter is out or what. I'm baffled and looking for solutions any takers? None of my 12 volt house items work.

**creativepart** · 02-21-2020, 12:18 PM

So, you have AC power but no 12v power? And your battery disconnects are all turned on?

Can you find your converter and check power in and out of that device?

JerryG · 02-21-2020, 12:28 PM

Not sure if I'm eletrically inclined enough to know if I can, I'm more mechanically inclined. I'm assuming its in the compartment with my inverter?

**creativepart** · 02-21-2020, 12:58 PM

Get your electrical diagrams from Winnebago's website for your model/year and look for it there.

JerryG · 02-21-2020, 01:32 PM

I fixed it. I disconnected everything, turned every switch off disconnected my battery’s then hooked everything back up plugged it in, threw the switch and everything came back on. I guess I will never know what the issue was unless of course it happens again. LOL

Morich · 02-21-2020, 01:34 PM

Okay, sounds like you've got the right thinking, just not too much into the electrical, so we need to work that direction. I can tell it's a bit short on the electrical side when you mention 300 amp! Or maybe that was meant to be 30 amp? No big thing.
But with a meter and knowing where the fuses breakers are is a good place to start but there can be other things. I've occasionally been known to forget to turn things on!
So looking at the breakers or fuses, there should be some which are 110AC from power coming into the RV or the generator. So it's worth checking that power is going though breaker or fuse to get to the converter that makes part of that into 12VDC. One quick way to see that power is actually getting to the RV is to check things like the microwave that use 110AC. Lights on it, you can skip to getting it from the AC side to turning it into DC. Another "quickie" is to find if it is ALL the 12VDC that's out by checking a bunch of the stuff that works on 12V. Lights, the furnace, frig all use 12VDC so if they are ALL out, look for the problem being something like the feed to the converter. There should be a fuse or breaker for that as a single item.
I'll do a little searching for drawings and get back with some better ideas.

EDIT? Whoops. Got the problem fixed and great!!! There are times when breakers are not actually making good and turning them off and on CAN actually fix the problem.

JerryG · 02-21-2020, 02:05 PM

Yeah I suppose I lucked out this time. Sometimes it’s better to be lucky rather than good. I appreciate the replies though. It’s a bad feeling when you have no idea what happened. I have never been shy about asking questions.

Winterbagoal · 02-21-2020, 03:39 PM

Quote:

Originally Posted by Morich

Okay, sounds like you've got the right thinking, just not too much into the electrical, so we need to work that direction. I can tell it's a bit short on the electrical side when you mention 300 amp! Or maybe that was meant to be 30 amp? No big thing.

Ahem....between an inverter and the 12V coach batteries, perhaps?
https://shop.findmyrvparts.com/monac...0-p/190175.htm

Morich · 02-21-2020, 04:50 PM

Quote:

Originally Posted by Winterbagoal

Ahem....between an inverter and the 12V coach batteries, perhaps?
https://shop.findmyrvparts.com/monac...0-p/190175.htm

Wow! I stand corrected. That gets into wires bigger than battery cables? Never thought of an RV with 50 amp service getting into 300 amp range.

powercat_ras · 02-21-2020, 05:45 PM

The 30 Amp breaker, and all the branch circuit breakers, in the Winnebago electrical box is a standard residential 30, 20, or 15 amp thermal-magnetic breaker that trips quickly if there is a short circuit, but does not trip quickly when there is an slight overload. The magnetic part of the breaker reliably trips if there is a sudden current flow, due to a short, of 15 times normal or more. It MAY magnetic quick trip, due to a short, with less than 15 times normal current - depending on the breaker. The more overload there is the faster the thermal overload part of the breaker trips, it's thermal trip is based on how many seconds with a given overload it will take for the wires being protected to get too hot to be safe. For example with a 10% overload a residential breaker will take 15 minutes or longer to trip.

In my experience with 2 different Onan 4.0s, the breaker installed by Onan inside the generator itself is way more sensitive than the RV breaker box residential breaker to overload AND ALWAYS TRIPS BEFORE THE RV ELECTRICAL BOX BREAKER. It's a pain in the butt.

One thing that would help that Onan does not do is use a breaker that matches their generator's rated output. The Onan gasoline powered 4.0 KY is rated to put out 33.3 amps, yet it's breaker is a 30 amp one.

One thing you DON'T want to do is tape the Onan breaker on so that it can't trip, because if there is a short when you are powering from the generator it's internal breaker is going to be what trips, not the residential breaker in the RV box. The 4.0 KY generator can not reliably generate the 15 times normal short circuit current, 225 Amps for the smallest 15A breaker, the residential breaker needs to reliably magnetic quick trip.

dickb46 · 02-26-2020, 10:43 PM

Your 300 amp fuse is real close to the battery bank, if you need that in the future.

tennessean · 02-27-2020, 04:40 AM

I recently returned from a 2 hour trip and had ran the generator to stay cool.
When I plugged in to shore power-nothing. Restarted generator-all ok.
Problem was a loose neutral wire in the transfer switch.
Check your connections

HappiHenri · 02-27-2020, 12:34 PM

It sounds like the breaker(s) they are referring to are those directly on the generator itself, right next to the Start switch. These are the 1st "line of defense" for your electrical system, and often get tripped if you have too much load on the circuit when turning on. This is one reason why they tell you to make sure most electrical devices (such as A/C) are turned off when 1st starting your generator - they do not want the gen to be subjected to a sudden sharp spike when it connects.

Most Winnebagos have a great Power Panel which helps show you what is going on electrically. So after you start your generator, and after it "boots up" (connects electrically) this panel will display (1) that the generator is connected and (2) total 120v AC load. This is very useful because it not only shows you that the gen is putting out power, but how much load you are subjecting it to. If you suddenly turn on the A/C, and then the electrical switch to the water heater, and possibly have some other items turned on (such as the microwave) you can easily trip the gen circuit breaker. Once this happens you will still hear the gen running, but no power is coming out of it. Again - this is the purpose of the power panel - you will see how much load you are pulling.

We have a 2005 Adventurer with an Onan 5500 watt gen. I know that the MAX I want to try and load it with should be <50 amps. If I turn on our HVAC basement Heat pump I will usually see ~30 amp draw immediately. Knowing this I also know to avoid turning on other high draw items - such as the hair dryer, microwave, or electric water heater - because these may overload the circuit and trip the breaker.

Your problem - as others have identified - was that your converter was not charging your batteries when your gen was running. The converter converts 120v (from shore power OR from your gen) to 12v DC. This is used to charge up your house batteries, and to power all your 12v circuits - such as lights and inverters. Most important to know is that your refrigerator also relies on 12v to operate it's circuitry. Even though your refrigerator does not cool using 12v DC power, it's control circuit board and internal lamps do need that 12v to function. So if your 12v house batteries get discharged your refrigerator will no longer function.

So - it sounds like you heard your gen running and assumed it was charging your batteries, but is appears it was not. So use your power panel to see what is going on.

Good luck!