12v fuse board

[tom68]

Hi,
New to the forum hello all glad to be here.
I'll get right to the problem.
I have a fleetwood ralley year 2000 . I replaced the bottom of the magnitek 6300 series converter with a WFCO WF-8935-MBA 35 Amp Main Board Assembly.

The reason I switched is because the Mag was not charging batteries and 5 of the 8 fuses had 17v on them. Now I installed the wfco and now 5 of the 8 have .06 v which is nothing. the three that work have proper 13.6v Can't figure this out. This is when pluged into 30amp service.

[tom68]

Well I'm getting 13.5 all across the fuse board. I did what you said hooked up a red jumper from that middle top eyelet over to the red positive lug.
leaving the green wire on also.
Thanks for all the great tips from you guys.
And a speicial thanks to DrewE.

[DrewE]

I would guess you ought to remove the green wire, or connect it to the rest of the positive bus somehow. The best would be to figure out where its other end is: it ought to just go to the converter area, and probably isn't connected to anything there, but it's certainly possible that somebody could have altered things around in who knows what ways in the past. Working on older RVs (or houses or cars or whatever) can be somewhat akin to an archeological exploration at times.

It would of course be best not to leave a live wire with the other end loose and not connected to anything.

[tom68]

DrewE,
One thing I am confused about. That eyelet in the middle top of board.
Do I leave the green wire on this and also attach the jumper from there to the red positive .

[tom68]

Thanks DrewE,
This uograde came without instructions. Thanks for showing me this procedure . Looks like it will work.
I will try it this afternoon. I will let you know if it works.

[DrewE]

Your DC distribution board has two separate sections, and you've only connected to one of them. You need to tie them together. There are two positive connections (one of which is more of an eyelet at the top of the fuse panel, which originally had a blue wire from the converter attached to it). See this page for some good pictures and descriptions, and a summary of this issue at the bottom.

On the original converter, the three (that now have power) were connected to the battery all the time. The other five (that don't have power) were "unfiltered" and connected to the converter output. There was a relay in the converter that would switch them over to battery power when the converter wasn't operating because you weren't connected to 120V power.

The new converter doesn't have this split output, and supplies nice clean power to everything. You just need to jumper the two positive leads to tie the two positive busses together.

[tom68]

It's wired right. I've got the red pos and white neg in the right place.
I have the 3 other wires white in that buss bar where all the other white wires go.
I have the black going in to the circuit breaker.
I have the green going up to the top of the fuse panel where the old blue wire went which is also a ground.
Thanks, but still no voltage on 5 of the 8

[RoyB]

I suspect you have miss-wired something...

I think the WF8935 has a RED and a WHITE wire coming off the 12VDC terminals.

WHITE is the NEG -12VDC (GND) and the COLORED RED wire is the POS +12VDC wire.

The only other connections you should have on the WF8935 board was the WHITE-BLACK-GREEN wiring from the 120VAC circuit breaker.



This is the basic wiring idea... I don't have a pictorial of your MAGNETIC unit but should be similar to this...



BESTCONVERTERS should have a writeup for you to use on replacing the Magnetic converter with the WFCO converter.

I am surprised you picked the WFCO WF 8900 series units as they don't have a good track record of not going into BOOST MODE smart mode charging... Most of us have had better luck with the Progressive Dynamics PD4600 or PD9200 series smart mode converters. They fit the same location.

The REVERSE POLARITY are usually two large value FUSES off-set to themself. These could be on the 12VDC distribution board.

This is a pictorial of the WFCO 12VDC distibution board.
You can see th two REVERSE POLARITY FUSES off to themself here...

[tom68]

I unhooked the neg battery lug plugged into 30 amp ser same problem 5 of 8 no voltage. Thanks so far from you guys. anymore ideas.

[ksg5000]

Check Bestconverter.com which has detailed writeups on how to change out your converter.

Been many years since I made the conversion but I seem to recall the old magnatek had filtered and unfiltered fuses - when you make the conversion I think you change the wiring so that they are all filtered - probably illustration on Bestconverter.

[DrewE]

I think at least some of the Magnetek 6300 series had a sort of internal transfer switch arrangement where certain circuits were connected to the 12V battery (presumably those that needed "clean" DC power) and others were switched between battery and converter power by a relay. This means that the DC distribution panel has two supply busses. With a more modern converter/charger, these should all just be connected together to form one bus.

It sounds to me like probably your (former) switched bus isn't connected to anything anymore.

[tom68]

New to RVing . Where would I look for the reverse polarity fuses.? Near the batteries?

[Sloop_Smitten]

Check to see if one of the two reverse polarity fuses is blown. Maybe some of the utility fuses route through one and the rest through the other. Just thinking out loud.