1996 Patriot - Freedom 20d inverter woes

[Vittorio Bares]

First post, never owned an RV previously - I bought this rig in December and drove it from West Virginia to NH. The only thing we noticed was there was no voltage in the electric receptacles. I've found wiring diagrams, read the manuals and searched the forums.

Before I go off and buy a new inverter, I'd like to make sure I've done everything to confirm the unit is needing replacement.

I think I've determined that the inverter function is inoperable (charging works fine).

AC current is fine with the generator running and I do have the inverter remote installed in the bedroom.

I believe the basics are these (assumes no shore power), with RV engine running:

• Alternator generates voltage DC (13.8v)
• Alternator voltage is delivered to chassis batteries and to the inverter
• The inverter then acts in 3 ways
  • Perform as a smart charger to charge the house batteries
  • Convert DC current to AC current and deliver power to the main panel
  • If AC shore or Generator power is detected, the inverter only acts as a charger to the house batteries

Then we have the inverter remote that controls the inverter behavior.
I've set the dip switches in the following way

• Dip #4 - on, to allow charging to be controlled by the on/off switch
• Dip #5&#6 - on/on, to disable idle sensitivity

(I'll reset #4 back to auto charge when we're ready to camp)

LED Panel shows:

• INV/CHRG - on
• DC Volts - 13.0
• DC AMPS - last/bottom LED is on

According to the manual troubleshooting guide (page 40), if the #1 LED (count starting from the bottom) of the DC AMPS LED set is illuminated, this indicates the inverter has shut down for some reason.

On the inverter end

• Power switch is off - as per instructions w/remote switch on
• No breakers have tripped (front panel)
• Insured internal fuses are ok (2 on front panel circuit board)
• Insured the ribbon cable from the front circuit board to side board is plugged in
• Tested for power coming from AC output 1 and AC output 2, no current

Checked the GFCI receptacle in the basement was not tripped (of course with no current from AC out 1&2 there wouldn't be any here either).

Checked all fuses near the multi-battery isolator - all good.

Verified that the coach shut-off was functioning and was set to on.


Is there anything else I should check?
Is the conclusion that the inverter function (probably transfer switch inside inverter) is toast?


Thanks in advance for any advice the community can offer

[Jerry Carr]

I'm not sure about your inverter or it's hook ups but on our 06 PT I would need to unplug the phone line at the inverter location then re plug it to be sure that the unit it talking with the control. I would give it a try.
   

[Bill Lampkin]

When you are plugged into shore power, do you have 120v at receptacles? Does the microwave and or refrig work on shore power? When plugged into shore power, your inverter acts as a 'pass thru' and just allows the shore power to power the receptacles. What Jerry said, you may need to cycle or 'reboot' your inverter. Check online for your inverter manual, if you can find it and see if you can reboot the inverter. And welcome to this world of head scratching; it will all make sense sooner or later!

[Gerald Farris]

If the pass thru relay in your inverter is your problem, every thing in the coach will work except the inverter feed circuits like the microwave and about half of your base plugs. The rest of the circuits will work fine like the A/C units, refrigerator, and about half of the base plugs. This is true with shore power or generator power.

Since you said that the AC current was fine with the generator, I would check the input supply line or the transfer switch. If you need more help or someone to talk you through the diagnosis process, just call me. 713-254-4156 I am in Arizona {PST} time zone now.

Gerald 

[Eric Maclean]

Vittorio
With your inverter the battery power feed for the inverter is from the coach batteries the same cables that it uses to charge the coach batteries.
Your coach should have a duvac ( blue dinner diode isolator )on the firewall I front of the bed which allows the engine alternator to charge both the coach batteries and the chassis batteries  when running and still keeps then separated when not running.
The inverter requires good coach batteries in order to invert or create 120v AC as mentioned earlier the inverter contains its own transfer switch known as a passthrough switch when 120 volts is applied to the inverter(shore power or gen power) via the 30 amp breaker in the bedroom panel power is passthrough this relay directly to your sub panel ( if you have one) and on to approx half the plugs as Gerald said at the same time this relay powers up the inverters battery charger and charges the coach batteries using the large cables running to the batteries.
However when no shore/gen power is available the relay drops out and connects the inverter power to the same sub panel ( if you have one ) and on to the plugs etc.
If you have power passing through on gen power and not on shore power I would first check you power lead in making sure you have power on both sides of your 50amp lead in Leg 1 and Leg 2 on your shore power cord then move to you shore power/ generator transfer switch to verify it is passing both L1 and L2 through on both gen and shore power if you have passthrough at the inverter on generator you should have it as well on the shore power .

There are two pop out breakers on the inverter for the inverter out put but again if they were popped you have no out on the generator to the effected plugs either.
In side your inverter there are two glass fuses on the boards inside which could shut down the inverter and pass through
And of course the pass through relay is a common fail point but if it works on the generator it should work on shore power.
In order the have passthrough in the inverter there must be 120volts present at the inverter input via that 30amp breaker in the bedroom panel if one leg of your 50 amp shore power is not present you may not have power to that 30 amp breaker .
 
I think your problem is more a power input to the inverter than the inverter itself.
A word of caution ( do not back feed the inverter output ) as this will damage the inverter.
Sorry for the long winded reply
Hope some of this helps

[Vittorio Bares]

Thanks for the replies!

@Gerald - I'll try giving you a call, I sure do appreciate the offer - a live conversation is usually quicker.

@Jerry - I'm assuming the motor should be running when I unplug the RJ11 line?

@Eric - yep, no pop-out breakers are tripped on the front of the Freedom 20d
@Eric - have verified the two glass fuses are ok

@All - I'm suspecting the internal transfer switch since with the generator everything works as it should, but all non-12v circuits are dead without it.
- I don't have access to shore power at the house (for another thread), but gen power is working fine.
- As a few have mentioned, generator power power will activate pass-through, and the behavior of gen and shore should be the same.
- House batteries are about 1yr old, they each measure 6volts (4 of them)

Is there a way to bypass the internal transfer switch and have it deliver current to the 30amp breaker in the bedroom from the inverter? Or some way to test if the inverter is producing 120v internally?

[Bill Lampkin]

Did you have any luck getting the red led on the inverter to turn off?

[Eric Maclean]

The power should come through that 30 amp breaker from the bedroom panel and go to the inverter that is where the inverter gets the power to operate both the pass through to the output circuits and the charger in the inverter with out power from the 30 amp breaker in the bed room there is nothing to pass through.
I'm pretty sure from your discription that your probem is in the shore power transfer switch .

The transfer switch in the inverter only switches between the 30 amp input coming from the bedroom breaker and the inverter output produced from battery power.

The shore power transfer switch in the baggage bags ( on the driver side right beside the water pump cabinet) switches between power from your shore power cord and the generator power coming from the gen set.

If you have power passing through the inverter when running on the generator the inverter transfer switch is working .
Knowing that it would appear that one of the shore power legs on your shore power cord or shore power tranfer switch is not passing power to the bedroom panel.
Hope this helps
Eric

[Vittorio Bares]

Unfortunately, I don't have shore power at my home yet - so I can't test that part of the puzzle.

But, what we do know is that the transfer switch operates when either shore power or gen power is applied.

I do get current in the right places with gen power - so it would appear the transfer switch does work, or at least it is currently in the by-pass position.

I've also checked the house battery voltage from positive post to negative post - they read 12.22 volts. Which according to Gerald (thanks again for walking me through the logic last night) should be sufficient to operate the inverter.

The conclusion seems to point to the internal transfer switch (might be stuck in the by-pass position) or the inverter its self not producing current. Looks like I'll be replacing the inverter - will check back with the community once I get a new one installed and see if we got it right...

[Steve Huber Co-Admin]

Vittorio,
Before pulling the inverter, try the reset procedure Bill Lamkin outlined in a previous thread. 

"I had the same thing; I fixed it by doing a 'reset' on my inverter. Unplug from shore power, make sure the gen is off and won't start, turn off inverter switch at the inverter, open house disconnect. Wait a few minutes, then reverse the procedure. Fixed my battery charging and got rid of the 'thump.' I think what you are hearing is the 'Big Boy' checking for battery voltage. Anyway, I found the inverter reset procedure in my Beaver manual, and it worked!"
 
It's from  the following thread.  http://beaveramb.org/forum/index.php/topic,8842.msg60722.html#msg60722
Steve

[Eric Maclean]

Vittorio
If you are considering a new inverter this would be a good time to step into a new life sign wave inverter.
Eric

[Bill Lampkin]

I just replaced my Xantrex modified sine wave (MSW) inverter (RV2012) with a new Freedom SW2000 pure sine wave inverter. Simple enough swap, other than the inverter is bolted to the ceiling of the basement compartment. Installed a new remote panel too; you might be able to do the same reusing your existing phone cable connection, provided you use this kit:

http://www.xantrex.com/power-products/power-accessories/Freedom_SW_Telephone_Network_Cable_Adapter.aspx

My MSW inverter works fine, just had to swap out to pure sine wave as I installed a residential refrig.

[Vittorio Bares]

I did go out and try the re-boot procedure with no change in symptoms. (thank you for the suggestion)

I'm looking at the Magnum MS2812 - Talking to Chris at Tekris Power in NJ. Seems he has loads of positive reviews for helping folks out as well as standing behind what he sells - anyone here use him before?

Also, the MS2812 has built-in pop-out breakers, single-in, dual-out like the Freedom 20d, and should not need an additional sub-panel.

[Bill Lampkin]

Check out the required battery cable size for your 2800w inverter. For me, the 3000w Xantrex requires 4/0 cable and bigger fuse size. I opted for the 2000w unit so I wouldn't have to replace my 3/0 cable and 350A fuse.

[Eric Maclean]

I replaced mine with the MS2012 unit and it has worked out great the only draw back it has is it is not a life some wave pattern inverter and may be problematic with sensitive electronics although I haven't had any problem with that yet.
I added the Network automatic generator start unit which will start the gen if the batteries get low or if the coach temp gets too high works great for boon docking.
Only problem I have had is that my coach had no echo charger (battery combiner to allow the inverter to charge the chassis batteries) and the generator starts off the chassis batteries so after several cycles of starting and charging coach batteries the chassis batteries are run down and won't start the generator I rectified that with a magnum battery combiner which connects both battery banks when ever there is a charge being delivered to either bank.
The magnum remote is very good and the controls are easy enough to use and gives you way more information than the old freedom 20
Eric