Charger/Converter questions...

[Workinprogress]

I recently purchased a 2007 Fleetwood Gearbox, and have discovered this weekend that it has TWO charger/converters installed... one is a Magnetek 775 and the other is a PD9130. The PD9130 appears to be an add on, and the magnetek appears to be original. There is a battery cutoff switch installed in the trailer. I have 12v power in the trailer with the switch off while the generator is running, but NOT while plugged into shore power with generator off.... if I turn on the switch, I have 12v at all times obviously.

Why would someone add a second converter, and is this a common practice? Also, would they both be benificial, or should I do away with the older one and just run the PD9130? I'm a newbie with converters and have only seen one per vehicle in the past...

[wa8yxm]

Sounds like the "Doorstop" Magnatek had a bad bridge relay in it.
Now the model you have I do not know but the 6300 had two "Sides" if you will. Charger (about 3 amp) and converter (like 40-45 amp; but nasty) it converted `12o VAC into not 12 DC But 12 RMS Rectified DC.. Like I said Nasty.

When not on shore power a relay "Bridged" the two so the battery provided 12 VDC to the house. If that relay was toast.. Well. exactly what you found.

[time2roll]

11.8 could be voltage sag. Get down to 5 amps and then check.

[BFL13]

IMO, toss the 775, keep the 9130 as the converter, and get a 9160 to use as a portable charger for fast charging on generator. You have a Charge Wizard already, so you can use that with either one as needed.

A deck mount converter is a portable charger if it has cut-off jumper cables in its terminals

If you got a second set of 6s to go series parallel like many folks do, you can run the 30 and the 60 at the same time at 14.4v for more amps on the larger bank, assuming you have a big enough generator to run both chargers.

[Workinprogress]

The 11.8V was with the battery leads disconnected and straight to the meter... So maybe 4 or 6 gauge wire, whatever is factory on the converter? The 32A was with it connected, but it was a smaller AH battery so maybe it just wasn't taking the charge at full capacity of the converter. The 32a doesn't concern me as much as the 11.8V does... it kind of tells me that it is old and worn out, but I'm no expert, that's why I'm here! haha

[road-runner]

Workinprogress wrote:
Well, I threw it on the bench last night and found it putting out 11.8v and 32a... not exactly what I had expected to see, is that normal for the Magnatek 775? I expected 13+v and ~75A to a pretty discharged battery...

The older Magnateks had unregulated and unfiltered outputs, so it could be a little tricky to correctly measure what it's putting out. You'd need a true RMS meter at the least, and I wonder if it's even that simple? The darn thing could just be old and worn out, too.

[BFL13]

You bench test for voltage at the converter output terminals with no battery attached. Then connect to a discharged battery to test for amps. (and to see if the converter can hold its voltage under load--but you need fat enough wires so there is not a lot of voltage drop--perhaps why you see only 11.8v?)

The battery will accept a certain maximum amps depending on its voltage and state of charge. To see 75 amps you will need a bank of about 225 AH at below 65% SOC approx., being charged at 14+ volts.

You can also see the 75 amps from the converter if you also have a draw on the battery of over 75 amps, such as an inverter running a kettle. The battery voltage will be pulled down under load so it offers little resistance to the charger, so now it can do its 75 amps at its 13.x voltage.

[Workinprogress]

Well, I threw it on the bench last night and found it putting out 11.8v and 32a... not exactly what I had expected to see, is that normal for the Magnatek 775? I expected 13+v and ~75A to a pretty discharged battery...

[Workinprogress]

I will likely leave the brick in the trailer as a stowaway spare just in case as well, provided it passes the bench test experiment that I have planned.. Great advice.

I just purchased the Charge wizard to throw at the PD9130 as well... I just installed 100W Solar Panel for light duty maintaining batteries, just need converter for fast recharge when batteries get too low on occasion. I also carry a Automotive charger if a little more is needed.

So if this converter doesn't have enough kick to charge two 6v batteries quick enough, what do you all favor for the task in replacement if it comes to that later?

KMLsquared wrote:
I added a PD converter and wired it directly to the batteries but left the old junk in place, just disconnected, as a backup in case of failure.

Workinprogress wrote:
6 hours in the compartments of the trailer later.....

-Removed Magnatek Converter. Why have two. I didn't even test it yet, I will bench test later and report back on that..
- Cleaned up wiring job on the newer PD9130.
- Opened Generator Transfer switch to ensure cleanliness, etc.. All was satisfactory.
- Started post maintenance testing and discovered the following: When generator ran I had 12v in coach, on battery power I had 12v in coach, and while plugged in to shore power I now have 12v in coach. I did not do anything other than re-position things and disconnect the old Magnatek Brick... so why do I now have 12v on shore power but I did not before? Is it possible that the two converters were fighting each other or maybe the magnatek converter was truly junk and back-feeding the transfer switch and not allowing it to close in the contacts for the shore power?

Anyhow, everything works, everything looks neat and orderly, and I am happier that it is all simplified now. I will bench test the old Magnatek converter tonight just for piece of mind (science experiment findings to follow)...

[time2roll]

Don't over think it. If it works then you did the right thing.
Verify the battery voltage is 13.6+ for charging. And again if you don't have the Wizard get one. PD is mediocre at best without and works like a champ with it.

[KMLsquared]

I added a PD converter and wired it directly to the batteries but left the old junk in place, just disconnected, as a backup in case of failure.

Workinprogress wrote:
6 hours in the compartments of the trailer later.....

-Removed Magnatek Converter. Why have two. I didn't even test it yet, I will bench test later and report back on that..
- Cleaned up wiring job on the newer PD9130.
- Opened Generator Transfer switch to ensure cleanliness, etc.. All was satisfactory.
- Started post maintenance testing and discovered the following: When generator ran I had 12v in coach, on battery power I had 12v in coach, and while plugged in to shore power I now have 12v in coach. I did not do anything other than re-position things and disconnect the old Magnatek Brick... so why do I now have 12v on shore power but I did not before? Is it possible that the two converters were fighting each other or maybe the magnatek converter was truly junk and back-feeding the transfer switch and not allowing it to close in the contacts for the shore power?

Anyhow, everything works, everything looks neat and orderly, and I am happier that it is all simplified now. I will bench test the old Magnatek converter tonight just for piece of mind (science experiment findings to follow)...

[BFL13]

The PD9130 might be too low in amps for "fast charging" your battery bank, if you have plans to do generator powered recharging off-grid. To keep generator time short, you want more charging amps. Eg, two 6s or 12s with about 225 AH will accept 60 amps easily.

Doubling the charging amps does not halve the time, but it sure helps reduce gen time. Somewhere around 25 to 30% amps to AH of bank is good. Higher percentage than that is more than the batts can take.

[Workinprogress]

6 hours in the compartments of the trailer later.....

-Removed Magnatek Converter. Why have two. I didn't even test it yet, I will bench test later and report back on that..
- Cleaned up wiring job on the newer PD9130.
- Opened Generator Transfer switch to ensure cleanliness, etc.. All was satisfactory.
- Started post maintenance testing and discovered the following: When generator ran I had 12v in coach, on battery power I had 12v in coach, and while plugged in to shore power I now have 12v in coach. I did not do anything other than re-position things and disconnect the old Magnatek Brick... so why do I now have 12v on shore power but I did not before? Is it possible that the two converters were fighting each other or maybe the magnatek converter was truly junk and back-feeding the transfer switch and not allowing it to close in the contacts for the shore power?

Anyhow, everything works, everything looks neat and orderly, and I am happier that it is all simplified now. I will bench test the old Magnatek converter tonight just for piece of mind (science experiment findings to follow)...

[wa8yxm]

On a guess. Ther PD is wired direct to the battery on the battery side of the cut off switch. The magnetek is not working at all (Well. they never did work all that well) IF so. just turn the battery switch on.

Fact. Righ now if the park lost power I'd lose my A/C. everything else (Well the water heater If I wanted hot water might not work) TV would continue. Radios. Computers, Lights.. I'd have to plug my cooker in a different outlet. That's all... How do I know this.. happened several times over the last decade and a half.

[MEXICOWANDERER]

Think of it this way...

Magnatek does NOT make a CONverter

They make a battery destroying PERverter. It cannot charge a battery. It merely plays a game of "Tickle Me Elmo" with a battery. It's better than nothing as an emergency spare for a real charger