2001 National RV Dolphin. OK..it is old...but good. But..like some things old, parts are starting the replacement chapter. Some 2 years ago, replace the CONverter, as it was getting "weak". I called that preventive maintainance.Now...problem with the INverter...I'm guessing failure. It is a "Dimensions Unlimited, Model: DUI 12/400. A green light indicates power going in....but nothing is coming out. The INverter controls the very front of the motorhome, TV and all that, one outlet near the floor and a kitchen outlet mainly for the coffee maker. It also (strangely enough) controls the 2 outlets in the bedroom!Can't find anything on it on the 'net (too old?)...I have the owners manual that shows a pretty basic schematic.What I think is the BIG problem...it is a PLUG IN....and I just want to bypass the whole thing....to replace it would be around $1000, something i just don't want to do.Wires go into the back panel of this thing (never saw them)the INverter itself is screws into the wall...a plug comes out the front and (of course) plugs into a 110 outlet that gives me the power up front and the bedroom.Again...I'd just like to remove it...any ideas so I don't blow myself up? Or have a fire? From experience, I know I cannot put anything like a space heater on that line....it pops the GFI on the unit.

It appears that is just a 400WATT Power Inverter... Didn't read the specs on it but you would want it to be a PURE SINE WAVE MODEL so that no matter what gets plugged into it won't go up in the infamous BLUE SMOKE thing... Electronics and MSW type Inverters don't do well being used together. Should be pretty simple Install with two heavy wires going to the 12VDC Battery and a 120VAC outlet on it with GFCI breaker on it...Google ImageJust trace back on the two Battery cables and remove them from where ever they tie into your battery setup... Then just simply unplug the 120VAC cable... Have no idea how this would be installed in your setup on the 120VAC side. If your 120VAC Plug Male connector is hot (Reads 120VAC with a multimeter) after you unplug it from the Power Inverter and have shore power ON then you will have a safety violation and you must remove the wiring connections. It would be very unsafe to have a hot male connector laying around still energized with 120VAC power. i.e. someone may have hooked up a 'widow maker' double male plug short cable to back feed your 120VAC receptacles when shore power or generator is not being used. A very bad and unsafe idea... Two guesses who the 'widow maker' will be...A proper install would include a change-over 120VAC contactor when shore power or generator is not being used.Easy to test out just use a multimeter to make sure 12VDC is feeding the unit and when turned on with nothing plugged into it you should read 120VAC at its receptacle... A 400 WATT 120VAC power Inverter would draw around 32 DC AMPS from your 12VDC battery connections when fully loaded down...Most probably cause for failure is a dead 12VDC battery or bad 12VDC cables feeding it...This can be replaced with a much smaller unit in size like maybe the 600WATT PURE SINE WAVE AIMS Power Inverter model PWRI60012S available from AMAZON for less than $150 google imageI use the 600WATT AIMS PSW Power Inverter with two drop cords from it feeding a multi-TAP Power Cord with one located in the Home entertainment area and the other cord going back to a table top near our bed area. Its not wired into the trailer system just a couple of Multi-tap extension cords you can plug into when you need to power up something from 120VAC when off-grid somewhere... I have the multi-tap head mounted on the back of the table top with all wiring out of sight.. I usually only draw around 250-300WATTS from my 600WATT PSW Power Inverter with a few low wattage things... 300WATTS of 120VAC power will draw around 25AMPS from my 12V battery setup...Google imageRoy Ken

You have a Magnum Dimensions 400 watt pure sine inverter. Input is +/- 12vdc and a chassis ground. Output appears to be via a normal wall plug. Magnum has a trouble shooting procedure on their web site:Trouble ShootingI'd try that first. If it's dead they have a phone number in the trouble shooting page. Maybe they repair these?If not I'd buy a 400-800 watt pure sine inverter woth a plug output and install in your failed units place.Room should not be an issue because you unit is huge and it weighs 14 pounds. You'll be amazed at what will replace.

Pictures would be VERY HELPFUL !Are their any outlets that are NOT connected to your inverter ?The quick way to install an inverter and still have a SIMPLE bypass is as follows (it does assume you have access to some of you wiring) :Disconnect the wires at shore power plug.Connect those wires to a heavy duty 3 wire female plugGet a 12/3 extension cord that is long enough to reach from the back side of your shor power plug to where the inverter is mounted.Cut the male end off, but leave 2-3'. Connect this to the back side of the shore power plug.Make the rest of that cord back into an extension cord by install a new male end. Plug the neww male end into the inverter and leave the female end loose near the pigtail you put on the shore power plug.To use shore power, plug the pigtail in the the your AC wiring. To use the inverter, plug the inverter, plug your AC power into the the extension cord from the inverter.The other even simpler solution is, to have the extension cord from the inverter exit the trailer near the shore power and just PLUG IT IN. Of course you may not want to go outside in the morning in you pajamas to plug it in to make a cup of coffee !

I am assuming the front plugs into the inverter.. Does the inverter have power in (120vac) and pass through or is it always workingIf it has 120v IN and is an inverter/pass through then replace the inverter with a standard power outlet, Tape off the 12 volt leads, leave only the 120 volt leads connected to the power outlet. In fact you can even use an "extension Cord" type outlet (I kind of like this one, though I've yet to install it)Locking NEMA 5-15R Extension cord outlet on E-Bay

Bypass inverter? If it just has an output as shown above... just unplug.I assume there is a transfer switch to pass through power when plugged into the pedestal.Replace only if needed.

Bypass INverter? | Good Sam Community

MrWizard
Moderator
Apr 29, 2017
You have made confusing statements and it's hard to know what's going where with the wiring

Your inverter has a GFI out let on the front
WHAT'S ON THE BACK?
Is there a 120v cord with male plug ?
If yes then it has 120v power coming in and has pass thru
Just plug the cord from the front, into the power outlet feeding the inverter

If there is only red and black 12v wires going to the battery, then no pass thru

You can take the CORD END that used to plug into the front of the inverter and plug that into an extension cord

Take pictures of ALL the inverter wiring connections and post them here

Do Not use a cord with two male ends to back feed into your RV circuits
BFL13
Explorer II
Apr 29, 2017
" (damage may occur if an ) external AC power source is applied to the inverter’s
AC outlet or its hardwire output.
CAUTION: Be sure the inverter's circuit breaker or
fuse are turned “OFF” during installation."

EDIT--it has a "terminal block" for hardwiring the 120v output.

The manual linked earlier suggests it has a hardwire outlet but the drawing in that manual does not show it. Perhaps it does have one, and that is what powers his front receptacles etc. ????

He says it no longer works. The manual refers to an inverter circuit breaker and a high temp shut off.

It is very confusing. Note the manual warning not to back feed the inverter's 120v outlets with 120v. Also note the general warning not to ever use a "suicide" (male plug at each end extension cord) set up to power a circuit.
dougrainer
Nomad
Apr 30, 2017
Roadpilot wrote:
You have a Magnum Dimensions 400 watt pure sine inverter. Input is +/- 12vdc and a chassis ground. Output appears to be via a normal wall plug.

Magnum has a trouble shooting procedure on their web site:

Trouble Shooting

I'd try that first. If it's dead they have a phone number in the trouble shooting page. Maybe they repair these?

If not I'd buy a 400-800 watt pure sine inverter woth a plug output and install in your failed units place.

Room should not be an issue because you unit is huge and it weighs 14 pounds. You'll be amazed at what will replace.

The OP has a 2001 RV with a 2001 Dimensions Inverter. HOW could he have a Magnum Dimension when Magnum was not formed until 2006??????
NOT THE SAME INVERTER! Same name but not the same Inverter
The OP's Dimension was what a lot of Motorhome makers used back then. It has a 120 plug pigtail that plugs into the wall outlet in the cabinet. All he has to do is jump the 120 wires together and that will bypass the Inverter. Back then they thought 400 watt was adequate for entertainment systems. They were for a few years and then as the Inverter aged, they did not continue the 400 watt output. Here is a link to the smaller 300 watt. Doug

https://winnebagoind.com/resources/service/pdfs/2002-06%20Dimensions%20Power%20Inverter.pdf
MEXICOWANDERER
Explorer
Apr 30, 2017
Kudos dougrainer for excellent detective work.

Most pass through inverters use a sad printed circuit board DPDT relay. A separarte full size frame relay rated 30 amps like a GTE brand found on eBay is easy to wire and will outlast a circuit board relay 50 to 1. Enclose in a box. Use the normally closed contacts as the power pedestal circuit and the magnetic closed circuit for the inverter.

This is a fun project. I've done many of them to resurrect failed pass through perverters.
dougrainer
Nomad
Apr 30, 2017
MEXICOWANDERER wrote:
Kudos dougrainer for excellent detective work.

Most pass through inverters use a sad printed circuit board DPDT relay. A separarte full size frame relay rated 30 amps like a GTE brand found on eBay is easy to wire and will outlast a circuit board relay 50 to 1. Enclose in a box. Use the normally closed contacts as the power pedestal circuit and the magnetic closed circuit for the inverter.

This is a fun project. I've done many of them to resurrect failed pass through perverters.

NOT detective work. I KNOW what the **** I am doing:B I worked (we also sold) on National from 1993 until 2006 when they went under and Newmar also used the Dimensions model 400 watt 18 years ago and we also sold and I serviced them then. Still do. Doug

MY experience is because I have been in the RV service business for 38 years and I DO remember OLDER systems.
jerseyjim
Explorer
May 07, 2017
Thank you all again. This morning I removed the INverter.Did some easy rewiring...and it all works.

It just wasn't worth fixing....16 years and never used it. And and all those pop rivets to be drilled out just to replace the GFI ? Nope..but thanks again

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