Battery drain

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While plugged into AC, the battery is being charged. I'm sure the
constant charge wouldn't compensate for running the furnace, stove
vent or fantastic fans all day long, but what about occasional use.
How often and/or how long would be too much drain?

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Look at the specs for your particular converter to see what the total Amperage output at 12VDC rating is (might be on the info plate or you might have to call the manf with the model number in hand).

Anything more than that is using battery to make up difference. It really depends on how many hours in the day each appliance uses compared to how many Amp-hours the converter can produce -- battery makes up temporary shortfall during peak loads and then is replenished during slack loads.

If you are close, however, the actual voltage being put out by the converter might be somewhat low, which means it won't actually be charging your battery much (the current will flow from higher voltage to lower voltage, with higher flow when there is more differential voltage).

Pete and Rats

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Well, according to Tony at East Coast Trailer once you plug into an AC outlet your battery is completely eliminated from your trailers electrical circuit by automatic relay. The power converter nowe becomes your battery & total power supply. The battery still gets charged but thats all. You can take the battery out without effecting your electrical syslem.
How much juice your power supply will produce dependes on its rating. When your power supply is put under heavy drain it will start to warm up & a cooling fan will come on to cool it off. So if you hear a slight hum from the power supply thats what it is.
If you really over-load the power supply you'll probable start to pop fuses or circuit breakersor even burn the power supply right out.
I bought a used Layton Box trailer in Florida & I haven't had a battery in it for 5 years. But its plugged in & the electrical system works just fine from the 12 volt bulbs to the electric water heater.
If you read the book that came with your power supply it will basically tell you this.

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Orginally posted by Rich McCormack

While plugged into AC, the battery is being charged. I'm sure the
constant charge wouldn't compensate for running the furnace, stove
vent or fantastic fans all day long, but what about occasional use.
How often and/or how long would be too much drain?

Rich,

The Casita converter will power [b]all built-in 12 VDC loads and still have power left over to charge the battery. You won't have to worry unless you have some heavy DC loads added, such as a large inverter.

My 1999 Casita came with a Magnetek 6300 converter rated at 45 amps. That's lots of power. I upgraded mine to the Magnetek 7300 when the original failed.

The 6300, if Casita is still using them, uses the battery as a giant filter to power some of the circuits. If you're using any sensitive electronic devices, they should be powered from the filtered circuits which are the 12 VDC outlets. It'll run without the battery, but the voltage at the outlets will be unfiltered.

The 7300 is a regulated converter so all 12 VDC outputs are filtered. Running without the battery has no effect.

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Morgan said:

"My 1999 Casita came with a Magnetek 6300 converter rated at 45 amps. That's lots of power."
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But that's only the 'converter rating'. You can't get more than 30amps from shore power. The converter doesn't have any 'power' it just distributes whats fed to it.

Rich doesn't say it, but he must not be using any 120vac appliances in his question?!

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Orginally posted by PineConeDon

Morgan said:

"My 1999 Casita came with a Magnetek 6300 converter rated at 45 amps. That's lots of power."
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But that's only the 'converter rating'. You can't get more than 30amps from shore power. The converter doesn't have any 'power' it just distributes whats fed to it.

Rich doesn't say it, but he must not be using any 120vac appliances in his question?!

Don,

The 30 amps of shore power is at 115 VAC. That's 3,450 watts of power delivered to the trailer. The converter takes a portion of that power and converts it to 12 VDC at up to 45 amps. That's 540 watts of DC power available to the trailer. That's enough for all the built-in loads including the refrigerator if you should want to run it on DC.

The AC power distribution panel (in the converter cabinet) has separate circuit breakers to power the converter and other AC loads such as the air conditioner.

Rich asked about powering the DC loads, the AC loads are powered separately.

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Umm, guys, the amount of 12VDC available and whether or not the battery is still in the circuit when shore power is used is strictly a function of the brand and model of converter used. I have had 30A and 20A (@12VDC) Magnatek converters, but one poster above has a 45A Magnatek, so you can't generalize, you've gotta read the specs!

One of my previous converters (the one on my '91 Scamp) had a split distribution panel where some of the fuses were filtered by the battery. I didn't ever see the schematic, but this leads me to strongly suspect (until proven otherwise) that , the battery was always in the circuit, both as a filter and to charge it.

Of course in my case, I KNOW the battery is always connected because I removed the heavy converter and its dumb charger circuit and gave it to an RV place for parts, retaining only the fuse panel. If I need a charge or want 12VDC from 120VAC shore power I plug in my lighter and smarter battery charger and clip it to the battery, but I also don't have a lot of 12VDC stuf consuming power.

As a general rule, the higher the voltage, the more actual power you can get thru a piece of wire, which is why the power companies use those incredibly high voltages for their transmission lines.

This also means as a practical RV matter that when you have something like an inverter (you put 12VDC in and get 120VAC out), you want to keep the low-voltage wires as short as possible and go the distance with the higher voltage wires.

When I use my inverter on my truck batty to power my computer (truck batty recharges better because it's right there with the alternator, not back there in the trailer), I clip it right onto the battery with an 18" wire set and then use a household extension cord to deliver 12OVAC to the trailer.

Pete and Rats who don't know much about electricity except that some of the wires seem to taste good

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OK, I think I got it now. While plugged into AC, the converter converts 120 volt AC to 12 volt DC to power the DC lights, outlet and fans. I'd been a bit fuzzy on the converter end of the RV experience since day one, thinking the lights and outlet were powered by the converter but the DC fans (furnace, stove vent, bathroom fan) were still run stricly from the storage battery even when connected to AC...glad I got that cleared up. One more question. The converter that came with our 17' Casita LD is rated at 25 amps maximum continuous load. I assume a small part of those amps, maybe 2 or 3, is going toward charging the battery; so, that leaves me with about 20 (plus maybe a couple spare) amps available to run DC lights, motors and fans. Yes, no...? Or, is the converter priority toward the DC appliances with any available left over going toward charging the battery? BTW, Thanks for the informative input.

Rich

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Hi Rich.

Now, remember, I'm not an expert at anything, especially electricity (that's why I befriend Morgan, who's an electrical engineer!).... but up here, in the winter, we often run without the battery even installed in the trailer ... so I have first hand knowledge, etc, that all 12 volt fixtures, etc, run just fine along with any 120 volt stuff like microwave, Pam's hair dryer, heat strip on a/c.

As I understand it, the Magnetek converter has an intelligent charger built into the system ... in other words, if it senses that the house battery is really low, the charger will kick into high gear ... and just trickle charge when the battery is charged.

Now, in terms of the scheme of things ... the charger portion of the converter is not capable of fully charging the house battery, to the extent a dedicated charger is capable of doing ... which is why I carry a dedicated charger to charge up the the house battery after a long dry camping trip.

Sounds to me like you feel you aren't getting the charge out of your battery that you're expecting ... are you having a problem?

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Orginally posted by Charles Watts

Sounds to me like you feel you aren't getting the charge out of your battery that you're expecting ... are you having a problem?

Hi Charles

No, not having any problems, at least not with the electrical system. Just trying to pick the brains of the experts here to clear up some confusion about the converter I'd been harboring for the last 14 months. The only problems I've been having lately are the fridge turning off while on propane and broken pop rivets in the bathroom /kitchen cabinet walls.

Rich

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Thanks Morgan, appreciate your explination.

If I may raise my hand from the back of the class again::wave

On the 6300...

1. Is the 'charger section' of the converter separate from the 45amps the converter allows for the 12v circuits?

2. The charger supplies approx. 8 amps max tapering to 2 as the battery builds up?! So if your 'dedicated' charger is, say, 10-30 amp then the battery would build up proportionately quicker. But it's gotta be more than 8amps to outperform the converter/charger?

3. My 12v fuse panel allows for up to 9 circuits, 6 are used. With 45 amps available, I've assumed this is so 'things' can be divided up so one short circuit doesn't shut down several 'things'?!

Everything works fine, it's helpful to understand it.:o
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Rich:

Back to your original 'battery drain' question (oh, it was really the fridge on propane):

If your battery has a weak cell, it'll drain quickly. It only seems 'fully charged'. A hydrometer ($6) test will find it better than a voltage check.

There's a propane test that can be done on the fridge fairly easily (by someone who knows) to determine if the propane pressure at the fridge is correct. I remember some reports of this test, and an adjustment, which fixed 'fridge on propane' problems. Mabe someone knows more about this?!

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...as the robot always said on "Lost in Space".

I said, "My 1999 Casita came with a Magnetek 6300 converter rated at 45 amps." Wrong, the original converter was rated at 25 amps. The upgraded 7345 converter is rated at 45 amps. Please accept my apologies one and all.

Pignone Don,

1. The charger section of the 6300 is not separate in terms of power from the DC power section. If no loads are operating except the battery, up to 25 amps is available to charge the battery. The charge rate tapers off as the battery becomes charged. When the battery is fully charged, the the charging section drops back to "maintenance" level. If other loads are operating, that reduces the maximum current available for charging the battery.

2. See [1]. If you're not running the refrigerator on DC and you don't ahve a big inverter plugged in, the converter should charge the battery much faster than a free standing 10 amp charger.

3. Fuses (and circuit breakers) are used to protect circuits. Separate circuits are used to minimize the current in any one circuit. Each circuit is fused so that if the circuit draws excess current (like a short circuit), the fuse blows and interrupts power to the faulty circuit.

-------

The power supply in the 6300 is protected internally against overload by an auto reset thermal circuit breaker.

The 6300 has some DC load circuits (just the outlets in a Casita) connected to the battery charge section. This results in using the battery as a big filter. Any sensitive devices should use those circuits. The other devices like motors, lights and heating devices don't require regulated power.

The 6300 has a transfer relay which switches the unregulated loads to the converter when plugged in to ground power and to the battery circuit when disconnected from ground power. The regulated loads are always connected to the battery circuit.

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Orginally posted by PineConeDon

There's a propane test that can be done on the fridge fairly easily (by someone who knows) to determine if the propane pressure at the fridge is correct. I remember some reports of this test, and an adjustment, which fixed 'fridge on propane' problems. Mabe someone knows more about this?!

I posted a my experience in adjusting my LPG regulator on Casita Club. You need a water manometer to read up to 15 inches of water pressure. I think I also posted instructions for making such a manometer.

The LPG pressure should be 11 inches of water with appliances burning. There's a test port just ahead of the gas jet in back of the refrigerator.

The adjustment is easy. I would [b]NOT recommend trying this if you're not comfortable with it. If you're a mechanical klutz, take it to Bubba's.

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In the previous post, I used the term "klutz."

I didn't mean that to be derogatory. We're all klutzes at something. I'm a klutz at woodworking and welding and probably other activites. :) CBW must be a klutz at backing a trailer in the presence of trees. :wave

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Morgan:

According to Magna tek ads the charging capacity is 6-12 amps depending on the converter model, for converters rated at 25-45amps. But you say:

"up to 25 amps is available to charge the battery".

Please don't think I'm being critical here, I'm trying to clear the fog of confusion. But I don't think ALL the 12v power thats 'converted' is available for charging, is it?

(I'm not brave enuf to try the propane test.....U Da Man!!)

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Orginally posted by PineConeDon

Morgan:

According to Magna tek ads the charging capacity is 6-12 amps depending on the converter model, for converters rated at 25-45amps. But you say:

"up to 25 amps is available to charge the battery".

Please don't think I'm being critical here, I'm trying to clear the fog of confusion. But I don't think ALL the 12v power thats 'converted' is available for charging, is it?

(I'm not brave enuf to try the propane test.....U Da Man!!)

Don,

I don't know what to tell you about Magnatek ads. Here is my copy of the old converter (6300) manual that came with my Casita. Maybe this will help:


<img src=http://www.fiberglassrv.com/board/uploads/3dc2fb01d643f6300pg1.jpg/>

<img src=http://www.fiberglassrv.com/board/uploads/3dc2fb4b654686300pg2.jpg/>

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It looks like I was wrong again, this is what I read on the converter:

<img src=http://www.fiberglassrv.com/board/uploads/3dc2ff8249586converter.jpg/>

Trouble is, that's on a decal I added as part of the upgrade to the 7345. :bh My converter will charge at up to 45 amps, yours is probably less.

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Morgan:

.........so the wiring from the converter to your battery must be able to handle 45amps?! Guess I've got an old model.
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I'm finding there's a lot of performance differences just in the different MagneTek converters that will fit in the Casita.
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The site below has a diagram that may be how the (old) Magnetek converter works.

http://www.amplepower.com/apps/converter/index.html

Thanks for your posting of the MagneTek manual. I've been 'building' a Casita manual.

We've chewed on this subject quite a bit, I'm gonna give it a rest.

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Orginally posted by PineConeDon

Morgan:

.........so the wiring from the converter to your battery must be able to handle 45amps?! Guess I've got an old model.
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I didn't say that, Don. We were discussing converters, not wiring. Don't get me started on Casita wiring, that got me in big trouble over on Casita Club.

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Charles, one can't say " a Magnatek" will do something without naming the exact model and options. Kinda like saying "a Casita is 13' long and has an airconditioner".

That's why I recommend any specific questions should be referred to Magnatek with model number in hand, esp about battery charging over long periods (1-800-848-0934 is the most recent number I have scrawled in my Scamp manual -- my late Magnatek was a 3200, with code C B, 20Amp not smart).

It might help to think of all this charging and use stuf as water levels; when the converter "pump" is on, it sends water to all appliances which have been "lowered" a little by switching them on. The less charged the battery is, the lower it is. When nothing is on, all the water is available for the battery. When the converter is unplugged, the effect is like raising the battery so water can flow from it to whatever is on, but when the converter is switched back on, the converter is higher than the battery and the water again flows back to the battery to replenish it.

In reality, the converter is putting out more than 12VDC, and the amount which flows to the battery is in part dependent on how low the battery has been drained, as evidenced by its voltage. All the so-called capacity meters are merely voltmeters calibrated to a percent level of discharge.

Pete and Rats