12V Issue

[dreadstar1]

Hello All-

I have a 2013 North Trails 28BRS and I'm having an issue with the 12V port under the television when running an inverter (1100W)- There is a digital readout on the inverter that shows input voltage. I'd like to set this rig up to do some boondocking -

No Load: 12.6V
Flat Panel TV: 11.9V
Satellite Receiver: 10.2V


At 10.2V the inverter shows an under voltage condition and alarms. The voltage at the batteries is still showing 12.7V... Is there something going on in the converter?

Thanks in advance!

Mike Boger
2013 NT 28BRS

 

[pegmikef]

You might be suffering a line loss. My inverter has a pretty stout cable to hook to the battery and I know the wire to that port is pretty small and anticipate low amperage things like a TV.

 

[cookie]

I agree with the line loss caused by small gauge wire.
You would probably be best served to mount the inverter as close to the battery as possible and use heavy cable to connect to the battery.
Then run an extension cord or add a dedicated circuit from the inverter.

Peace
Dave

 

[Harold_ON]

I had a voltage problem with my slides.
They wouldn’t move. Upon checking with a voltage meter there was
a 2 voltage drop from the battery to the terminal. Found all the
connecters attached to each wire were loose. Had to replace with
better connectors as well as some new wire. Wires to the battery I
replaced with car starter cables. I replaced the ground block with
a much better quality. The original was starting to corrode. Then
covered all the connectors with a corrosion blocker. This maybe a
problem you are having, the connectors ends on the wire not clamped
tight enough. Mine were very loose.
It helps when your son is an auto mechanic.

Harold
Ontario, Canada
2011 Big Country

 

[recumbent615]

I would also suggest that the inverter be placed as close to the Battery as Possible with a Large gauge wire. There is a reason that Edison's form of Direct Current (DC) electric did not win popular use in the US. Line loss - Something that Alternating Current (AC) does not suffer from as much.

This is not to say that some of your issue might not be lose connectors - but the 12 DC outlet is not designed for a high load.

Kevin

 

[evolvingpowercat]

An 1100 Watt Inverter would need to be on an 80 amp fuse and use 6 or 8 gauge wires to both battery and the frame to carry that kind of load. A 12V outlet is on at best a 15 Amp fuse and being fed with 14 gauge wire. It will work with a 100 or 200 watt inverter made to power a laptop computer but not any larger. When I installed a 1200 W inverter I used a Amp kit I bought at WalMart that was the cheapest way to buy the wire, the crimp connectors, the 80 amp fuse, and the 80 amp fuse holder all at one shot. I am barely able to run a coffee pot or my 0.9 cubic foot microwave with the 1200 Watt Inverter, which was what I was trying to accomplish with that large of an inverter for occasional use while dry camping.

 

[dreadstar1]

Thanks to all of the replies. I have a ~190 CCA battery setup. Would any of you recommend a whole trailer (~3000 W) inverter?

Thanks-
Mike

 

[cookie]

One thing you have to consider if you go with a whole trailer setup.
Your battery has a limited amount of capacity so you would still have to watch your usage.
I have had intentions of installing an inverter for some time now. Thanks for reminding me to get it done.
Mine will have one dedicated circuit using an extension cord to run a CPAP.

Peace
Dave

 

[evolvingpowercat]

Thanks to all of the replies. I have a ~190 CCA battery setup. Would any of you recommend a whole trailer (~3000 W) inverter?

Thanks-
Mike

In a word, no. A 3000 Watt Inverter delivering full output would be drawing 250 Amps from your 12 Volt batteries. It might help us advise you if you told us what it is you are trying to do. It sounds to me like you need a generator to feed the shore power connection on your RV, not an inverter tied to 12 volt batteries given the kind of power you seem to think you need.

 

[dreadstar1]

In a word, no. A 3000 Watt Inverter delivering full output would be drawing 250 Amps from your 12 Volt batteries. It might help us advise you if you told us what it is you are trying to do. It sounds to me like you need a generator to feed the shore power connection on your RV, not an inverter tied to 12 volt batteries given the kind of power you seem to think you need.

Randy-

Thanks- I'm not trying to run any of the high power items (Air Conditioner)- I would like the AC outlets to work so that I can possibly nuke a cup of hot chocolate or watch TV (w/ satellite receiver) when I'm in quiet hours and can't run the honda generators...

Mike

 

[dreadstar1]

Also, I noticed an error in my post- I have 190 Ah battery setup- not 190 CCA... 2x type 24 batteries in parallel....

Mike

 

[Invizatu]

Mike... I have a couple of small inverters ( 200 watt and 400 watt) . I can plug in the 200 watt inverter into the 12 volt wall outlet and run the T.V. and Sat. receiver and my lap top and my wifi, plus a few chargers ( cell phone etc.) for several hours with one 12 volt battery for several hours no problem. No need to go crazy on inverter size unless you just have to use that microwave!

Bret

 

[pegmikef]

We use our 40 year old camping stove top perculater (sp?) for coffee when we don't have shore power. Works great. I also use two Trojan 105s when we boon dock and they will run my fan or furnace all night with plenty of power left in the morning. I just run one of the Hondas to charge them (unless it is hot, then I run both of them so I can use the A/C).

 

[evolvingpowercat]

I see now why you were talking about a 3000 watt converter after looking on Amazon.com The listings are over stating the real capability of inverters by talking about peak power not continuous power. What are being sold as 3000 watt are really 1500 watt, which is a reasonable size for what you are trying to do. That will run a microwave or coffee pot, but not both at the same time.

For what you want to accomplish, I suggest you can do a 3000 watt peak / 1500 watt continuous or similar modified sine wave inverter. Such as: http://www.amazon.com/Pyle-PNV3000-...&sr=1-48&keywords=modified+sine+wave+inverter

You will need a modified sine wave inverter or a full sine wave inverter to be able to use the microwave without damaging it. Personally I just power what I want to use (microwave, coffee pot, TV, etc.) right into the 120 Volt receptacle on the inverter with a 15 foot 14 gauge extension cord. Personally I put the inverter under the bed above the water pump and added a door I can open to turn on the inverter and plug in the cord. Here is a link to the post: //heartlandowners.org/showthread.ph...to-my-Edge-M21?p=256632&highlight=#post256632

If you feed the entire 120 Volt camper like you want to, then you will have a problem where you will be powering the 120 Volt to 12 Volt converter, which will cause you to lose 500 - 600 watts of your inverter output trying to charge the 12 volt battery, but there is 20 % conversion loss this is bad and a waste. However you could just remember to always turn off that circuit breaker and remember to turn it back on when not using the inverter.

Just to further explain - if you are using 12 Volt power to make 120 Volt power, you lose about 10 - 20 percent in the conversion. Now if the 120 Volt power is being converted back to 12 Volt in your converter (because you fed the 120 Volt inverter power to the whole RV) you lose some more, another 10-20 percent converting the 120 Volt back to 12 Volts. So without a single thing using 120 Volts, you will run down your 12 Volt batteries. But by turning off the breaker that feeds the 120 Volt to 12 Volt converter, you can prevent this.

 

[dreadstar1]

All-

Thanks! This discussion has really helped.

Actually, I had my eye on this inverter/charger:

http://www.theinverterstore.com/3000-watt-inverter-charger-12-volt.html

For $450 and the reviews I've read, it looks to be just what I'm looking for.

It looks like it will be a replacement for the onboard charger- The big issue that I see is the location of the current onboard charger- After all of the discussion of line loss, I don't think the trailer's cabling will handle it and I'll either have to mount the unit in the front cargo area (close to the batteries) or figure out a way to move the batteries closer to inverter... The former seems more practical than the latter...

In the mean time, I'll see about a smaller inverter set up as described in your posts- I like these forums! very helpful and nice to the newbie!

 

[evolvingpowercat]

Some concerns about your plan:

The transfer switch built into the unit is not rated heavy enough to handle the 30 AMP that is the shore power to circuit breaker box size
The current AC to DC inverter / charger in your camper likely is able to put out 55 amps to power your 12 Volt items and charge your batteries, and likely has a intelligent charge circuit that fast chargers then drops to slow charge then finally to float mode to maximize the life of your batteries yet minimize the charge time. It is not clear how smart the unit you are considering is.

You might be able to leave the current breaker panel and 12 Volt charge system the same and add a AC sub panel, with the transfer switch between the main panel and the sub panel - moving a couple of outlet circuits to that new sub panel. Of course we are getting involved in terms of skill required and cost and space it will take up.