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agesilaus's avatar
agesilaus
Explorer III
Jun 09, 2017

Electrical search continues

OK my efforts to figure out what the problem is has proceeded.

1) I have both a Power Dynamics converter (in that black electrical/fuse box) and a inverter
2) The converter is getting 120V when the unit is plugged in and is outputting 17 VDC. The wires vanish into a wall tho. But I assume someone routed that DC to the inverter.
3) The inverter has both a/c and the dc going in but seems to be dead.
4) Even tho the converter has 120V VAC in it is not supplying power to the 120V outlets. But that may be something whacky about the inverter wiring.


My thoughts are this. We have no need of the inverter. If we boondock we don't expect to be running 120 VAC appliances. So the non-functioning inverter is surplus to needs.

I'm thinking I can just route the DC output from the converter to the into the a/b switch and from there to the batteries.

I'm charging the batteries right now and will give that a try tomorrow.

Any thoughts or suggestions? My one question is whether I should just go ahead and replace the converter with WFCO panel with smart charging. That 17 V has me uneasy but that is unloaded.
  • agesilaus wrote:

    Any thoughts or suggestions?


    Didn't you start this discussion in ANOTHER thread ??
    If so, you should CONTINUE the discussion in the same thread.

    Otherwise all of the information provided there is effectively lost and folks get tired of chasing around to "fill in the blanks".

    Before you change anything, you need to know for sure how things are wired NOW.
  • 17 volts could be open lead. Once connected to battery and system it could drop down to the 13-14 volt range.
    Many larger inverters have a pass through feature. The inverter would be taken out of the circuit if turned off at the unit or 12 volt fuses pulled.
  • Power Dynamics? How old is this thing? Or maybe Progressive dynamics?

    17 volts is way too high. Seems odd as very few fail high. Do you have a second meter to verify? Or if the battery is low in your voltmeter they can read high. Otherwise I would replace with Progressive Dynamics or IOTA only as you mention off-grid camping.

    Inverter has AC connection in and out? Just no output? You can replace with J-box and a couple wire nuts if you prefer.

    I do not recommend WFCO. Get a PD or IOTA. New converter will be built into the new panel.

    http://www.bestconverter.com/PD4045-45-Amp-Inteli-Power-Mighty-Mini-Power-Center
  • The converter does not supply power to the 120 volt outlets and the dc voltage from the converter does not go directly to the inverter but to the batteries. The batteries supply 12 volts dc to the inverter for producing the 120 volts ac.

    Do you have GFCI outlets and have you checked them?

    Do you have breakers in your breaker box for the inverter? You could have one or two breakers depending on the model of inverter you have. And, have you cycled the breaker/s?

    Check for 12 volts from the batteries to the inverter. There is probably a fuse on the 12 volts from the batteries to the inverter and if you don't have 12 volts at the inverter it needs to be checked. On my coach this is a large 300 amp fuse. There may well be breakers on the inverter itself that may need to be reset by pressing on them.

    Inverters usually have a secondary breaker box for the output of the inverter. Sometimes the manufacturers hide them pretty well. I found mine by accident. If you aren't getting 120 volts when on shore power this is a good candidate for the problem.

    Also, the 120 volt shore power goes from your breaker box to the inverter and then out to the outlets. There is a transfer switch built into the inverter that switches to allow shore power to pass through and then switches back when you are using the batteries to produce 120 volts through the inverter. This transfer switch may have failed.
  • RoyB's avatar
    RoyB
    Explorer II
    This is the basic wiring configuration for a 30A Wiring Configuration...



    As you can see here every thing revolves around the 120VAC Power Distribution Panel where the Circuit Breakers are located and the 12VDC Power Distribution Panel where all of the ATC TYPE Fuses are located.

    The 120VAC Power Distribution panel is powered by the Shore Power Cable or Generator and the 12VDC Power Distribution Panel is powered by the 12VDC OUTPUT leads of the Converter unit and the 12V Battery setup.

    When running on Shore Power or Generator the Converter is also a DC Charger unit to maintain the Battery operation. This is why you see the Converter also called a Converter/charger unit.

    You can see at the bottom of this block diagram where when operating without Shore power or generator the BATTERY can also provide 12VDC power to an optional Power Inverter that can provide 120VAC Power for such things as 120vAC Receptacles or other 120VAC Appliances that may be plugged into these 120VAc receptacles. These are OPTIONAL for the most part but some of the newer high-end trailers may have this Power Inverter built-in with auto switchover circuits...

    This is to give the basic concept of the 120VAC and 12VDC Power in the RV units is managed...

    The original RV Trailer concept was to have all Installed appliances functional when on Shore Power or Generator but only the very necessary functions only available when on BATTERY only. The necessary functions being run off of the 12V battery setup only includes lighting, limited entertainment setups, with cooking and heater features being run from Propane energy.

    To have all of the installed appliances functional without Shore Power or Generator would require an optional POWER INVERTER setup to produce the required 120VAC being run by a very large battery setup and a robust way to keep the multiple battery bank charged.

    Lots of folks do not know the difference between the Installed CONVERTER/Charger unit and the optional POWER INVERTER units.

    Hope the simplified Block Diagram helps identify the 120VAC and 12VDC Power Distribution features of the typical RV units.

    Roy Ken
  • Your plan is a good one - connect converter directly to batts and remove inverter from the circuit.
    BTW, the converter doesn't supply AC to the outlets other than providing circuit breakers to protect them. The converter section itself plays no role in the 120V side.
    The 17V's is a problem - dont use that on the batteries. (or anything else in the RV - it will kill stuff!)
    I suggest a new PDI three stage converter.

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