Help! Power slowly died

[pault86]

The caregiver who helps take care of my elderly dad lives in a 1987 8721 Funlite FLL. A few nights ago she was running what for her is a normal AC load she uses all the time - air conditioner (not on highest setting), TV, refrigerator, and a 60 watt lamp. What we think is her master switch was in the "on" position.

Suddenly the lights began to flicker and then dimmed and went dark in about 5 seconds. The AC appliances also went off. There was no sound like a breaker tripping or a fuse popping but when she looked at what we think are the 12 volt distribution fuses there was a 32 volt 30 amp fuse blown - it had a hole in the middle.

She has not returned to the trailer but we are trying to understand what happened so we can talk intelligently to try to get help from local trailer repair folks.

Since the lights slowly went dim it seems like the 12 volt system switched to battery and drained quickly. Does that mean something like the water pump was frozen up and drawing too much current?

Also, if the fault was in the DC system, why did the AC appliances go off? No other trailers in the campground lost power so shore power was probably on and okay.

Attached is a picture of her power converter. It does not look original. The DC fuses are in the foreground of the picture. The 32 amp fuse that was blown was behind the yellow wire on the far right.

Can anybody help us understand what happened and what we need to do to test they system and get it repaired?

 

[pault86]

My caregiver's trailer seems to match the 12v schematic shown in the 1990 manual JackandJanet linked to in Williampie's thread, 4 DC fuses and no Master Switch.

The 32V 30A fuse that blew is connected to fuse position 5 as shown in the manual's schematic, but in the manual that position is not used. What circuit uses 32V?

I know nothing about the trailer electrical system except what I've read here on the forum and in the manual and I've never actually been in the trailer. My caregiver is bunking with her brother's family for now so I need to get this fixed quickly. Any help would be greatly appreciated. Again, the big questions seem to be:

1. What made the 32V 30A fuse blow?
2. If that is a DC circuit, why did we also lose power to the AC appliances?

Thanks!

 

[JackandJanet]

Paul - I don't have your trailer and I am not familiar with the electrical system in it, so I can only offer some "guesses".

First, there are no 32V circuits in the trailer - fuses are often rated at a higher voltage than they are expected to handle. The important rating value in the fuse is 30A, which is the maximum current it is expected to pass to components. A fuse generally blows because some component demands more current than the fuse (or circuit) is rated to handle. This is often caused by a "short circuit" which acts like a wide open pipe that passes a huge amount of current. But, there are other causes, including an old, "worn out" fuse.

I suspect that fuse is in the charging circuit of the battery, and when it blows, the battery no longer gets charging power. All the DC components in the trailer are actually powered by the battery, even when you are hooked to shore power, so if it is no longer being charged, then it will rapidly become depleted, especially if the battery is faulty.

Now, if that fuse is in the circuit I described, it is possible the battery developed an internal short which demanded a large level of charging current which in turn, blew the fuse. The first thing I would do is have the battery tested. If it will take and hold a charge, then it is not faulty and the problem was elsewhere. If faulty, though, it should be replaced and the fuse should be replaced too. This may fix everything.

What other AC components were in use in the trailer? Almost everything except the Air Conditioner and an oven or microwave can be run on DC power or propane. I would use propane for the refrigerator and hot water heater.

- Jack

 

[pault86]

Jack, thanks so much for your reply.

The fuse being in the charging circuit makes sense. We have ordered replacement fuses and tomorrow we will have the battery tested at AutoZone. I do know we need a marine/deep cycle battery, not a car battery, if we have to replace it.

The idea the problems are age related also makes sense. The young lady who owns the trailer bought it a few months ago from an uncle who had not used it for years.

The AC appliances that were in use for certain when she lost power were the air conditioner, a TV, and a 60 watt lamp. The refrigerator was also on, but she does not know if it was being powered by AC, DC, or propane. She does not know how to switch power sources for her equipment and, in fact, does not know for certain what equipment she has in the trailer. For example, she does not know if she has a water pump. She has not sighted it and the trailer is connected to city water at present so presumably it would not come on. I've asked her to take pictures of all the switches, fuses, circuit breakers, and controls in the trailer so we can try to figure out what she has and how to select the power source.

She is certain that the AC appliances that were on went off when the power went out. What would cause that?

Thanks again for your help, Jack.

 

[JackandJanet]

I wouldn't have expected the A/C to be running, even in Texas at this time of the year. Was she using a heat strip in it? She DOES have a water pump, but it would not be in use with city water. She certainly has to use AC power for a TV and a 60W lamp. I would strongly recommend she use propane for the fridge, hot water heater and that she use the trailer's furnace for heating, not an A/C heat strip.

I'm going to guess that a heavy draw on shore power may have popped the circuit breaker in the campground plug-in point (where the shore power cord was plugged in). I had that happen in my trailer shortly after we bought it when I attempted to run the A/C, refrigerator and hot water heater on shore power, as well as using the converter to charge the trailer's battery. Since that happened, I use shore power only for the A/C in the summer, if in a campground with hookups. If the battery was defective, it could easily increase the total current draw, leading to the other problems.

Yes, have the battery checked, I think it's bad. If so, replace it, but install the new fuse with the battery out and shore power unplugged. Then, install the battery and see if the interior lights work. If so, plug the shore power in (checking the circuit breaker at the pedestal, to be sure it's on). Then, make sure the fridge and hot water heater are running on propane. The propane tanks may need to be filled, of course. Propane should last a long time in the trailer - I think two full tanks could easily go a month, total. Refill them as each empties.

Again, I would also use the trailer's furnace, not an A/C heat strip.

- Jack

 

[pault86]

Jack, I think you nailed it, but it wasn't the pedestal breaker that popped.

Here in College Station December days are mostly in the 70s, but we do get an occasional day in the 80s or low 90s. The day Sam - the gal that owns the trailer - had the problem was a hot day. When it is cold she does not use a strip heater, she uses the trailer furnace.

Picture number 1 shows the old battery, a car battery and obviously shot judging by the white powder in some of the cells. Maybe that indicates an internal short. Sam did get a size 24 marine battery to replace it at Sam's Club.

Picture 2 shows the shore power pedestal breakers did not pop. On the left side of the pedestal a pigtail is plugged in that attached via a yellow adapter to a jury-rigged shore power cable Sam was using. Her normal shore power cable was too short to reach the pedestal, but the uncle who owned the trailer made a jury rig with the extension cord, adapter, and pigtail shown in the pictures.

Pictures 3 and 4 show it looks like the yellow adapter melted from the over current. The only thing that stopped a fire was the 30 amp fuse blowing on the charging line.

Next week the replacement charging line fuse should arrive and Sam has an appointment with a some professional repair people - https://www.c5mobilervrepair.com. I think she needs to ask them to make up a shore power cable that will reach from her trailer to the pedestal and then follow your procedure to make sure everything is back working.

Does that sound right? Is there anything else we are missing?

Thank you again for all the help and quick replies. Sam has now found her water pump and water heater - she was looking right at them but didn't know what she was looking at. She is trying to use the trailer as a cheap alternative to an apartment. She pays $400 a month lot rent that includes her water and electricity, so she would like to use electric power as much as possible rather than propane.

I'll post again next week to let you know how she comes out.

 

[JackandJanet]

OK, the melted plug certainly explains the loss of AC power and then the battery went too. Possibly, the battery pulled too much charging power in an internal short condition, which started the whole process.

What is the black cord plugged into in the 2nd picture? Is it the 50A outlet? HiLos should only be plugged into a 30A source.

It DOES look to me as though the jury-rigged extension was not able to handle a 30A draw. It looks like those components are 15A, but I'm kinda "guessing".

- Jack

 

[pault86]

That's a great catch about the 50 amp breaker, thanks. I will ask Sam to check with the landlord and make sure she is on 30 amp service. Here is a picture that shows the breakers and plugs a little better.

I think the white powder in the two battery cells is what is left after they shorted and boiled the liquid out, so just as you suggested. Using a car battery shows this tailer has not been well cared for in some time.

Thanks, Jack, so much for your help. Looking through the forum I have learned a lot from your posts and you have certainly helped a lot of folks out. Thank you. I'll post after we get a proper shore power cable and follow your procedure to see if we can get back up and running.

 

[garyk52]

Hate to say this but I think she needs to buy a 30 amp extension for rv's and a 50 to 30 amp adapter. I can't tell but it looks like the extension cord is 14/3 or smaller, not nearly rated for what she needs.

 

[Elaine and Bill]

Too many years ago to remember the details, we had a "surge" many years ago at a State Park that melted our 30A plug, had to have the entire power cord replaced! Fortunately, we lived near the HiLo repair shop in Ohio!

 

[kirby-HILO]

my opinion I agree with too much power/voltage being drawn through too small of a wire- uncle tried but no - and agree there is no reason to be plugged into both 30 amp AND 50 amp as shown in pics- again , uncle tried but no , you are replacing battery and fuse but may also have to replace whole 30 amp cord but only a good enough electrician would know, best wishes, kirby

 

[pault86]

Sam's camper is back working and she has survived some 40 degree nights. When she hooked up the new battery she said lights lip up she had never seen on before, in particular the oven light and outside running lights. The oven light has a switch but she has not found how to turn the outside lights off. Anyone know where this switch might be?

I'm not sure we've solved the problem of using an underrated shore power cable. The guy who does electrical work for the campground said to get a 50 amp extension cord and a 50 to 30 amp adapter. She hired a pro to cut off the jury-rigged 110 volt 3 prong adapter grafted on to the Hi-Lo's built in 30 amp cord and install a new yellow 30 amp plug. She ended up with the rig shown in photo 1. The 50 to 30 adapter plugs are red, as are the 50 amp shore power extension plugs. Since the 50 amp breakers were not replaced with 30s at the shore power pedestal I think she could still damage the camper's built-in shore power cord if she has another short. Is that right?

What really held her up was the 30 amp fuse that blew on the 12v charging line. Could not find these at electrical supply, auto, or hardware stores. Ended up special ordering from Walmart but they took 8 days to come in. Shown in photo 2, now she has some spares.

Thanks to everybody who has helped out with a response, and especially JackandJanet.

 

[Elaine and Bill]

Our outside porch light was on the underside of the upper cabinet near the door. The outside front light was located under the front top shell on the door side of the trailer. The skirt light switch was located below the master-switch on the left as you entered the trailer. Hope this help!

 

[JackandJanet]

Paul, as far as I know, plugging the camper into a 50A outlet should do no harm as long as the camper's draw is 30A or less. The 50A outlet does not "push" current into the camper, it just allows up to a 50A "pull". Now, with that in mind, our modern converters are rated at 45A, which means they could pull up to that value at least for a short period. However, a faulty circuit in the camper such as a short circuit or an internally shorted battery could, I suppose put even more than a 45A draw on the campground pedestal. But, the converter has internal 30A fuses (like the one you are replacing) that would blow in this case to protect the circuit that is causing the large draw from overheating and possible fire.

So, I think you are OK with the 50A to 30A adapter. However, if she were plugged into the 30A outlet, then in the event of an excessive draw, the campground circuit breaker would probably trip before the trailer's fuses would blow. This would really be a better way to supply the power.

- Jack

 

[pault86]

Thanks Elaine and Bill - I'll pass the info on to Sam so she can look for the switches.

Jack and Janet - thank you, thank you for so much help with this problem. You diagnosed it without even seeing it. I am so thankful for your help.

Hope everybody had a Merry Christmas and Happy New Year.

 

[JackandJanet]

You're most welcome, Paul. Glad you got Sam's electrical problems sorted. Have a great New Year!

- Jack