Inverter shutdown middle of night

[Rlynxgolfer]

We have a 1000w inverter on our 2006 Dynamax Dynaquest 320.
Plugged into 50 amp service.During middle of night we were awakened with
Alarm of a safety shutdown of the inverter reaching 10.5 volts.
This is first time this has happened. When I checked it out the coach was still plugged in and showed both legs Hot into the panels main but no power on the
inverter side of the panel due to inverter shutdown.
Why would the inverter switch to battery inverter power when plugged into shore
power. Could we have lost shore power during the night,and why didn't the inverter go back to shore power when shore power came back on if that was the case? On the inverter side of the panel we had plugged in electric blanket, CPAC machine,
and phone charger and 1 IPad. so I guess that would take the battery down but
again we were on Shore Power.
All seems to be good now but always on my mind now.
What could have happened?
Thank you

[Bama Rambler]

Definitely sounds like you lost 120volt power to the inverter. Whether it was a power outage or just loss of power internally, we don't know.

It is strange that it didn't switch back to shore power when it came back on. I assume that shore power was back on when you checked it.

What did you do to get the inverter to switch back to shore power?

[Rlynxgolfer]

The shore power cord had the red indicator light on so I came inside and took the power panel cover off and tested the main breaker had 117 volts on each leg. Of course the inverted side of the panel was dead nothing coming from inverter side. Went out and
Unplugged and plugged back in still nothing.Went to inverter and went thru all setting
just adjusted the alarm to silence.Waited for daylight.
Finally broke down electric and water to pull off lucky the slides came in. Started up
Coach and the inverter went to normal readings and started to Bulk charge the batteries.
We stopped at another campsite that evening set up as usually with 50 amp service.
Inverter went to ASB mode then to FUL. no problem through night woke up in morning
Indicator still said FUL.
Would I turn off inverter while traveling?
Thanks for help

[mikakuja]

We had a Paralax transfer switch go bad in one of our previous trailers that caused an issue similar to what you are describing.. I searched but couldn't find the source of the problem or re-create it despite my attempts. As usual, and at the most inconvenient time, we lost all 110v power to everything in the trailer one morning while switching from shore to inverter power.
Thankfully I was able to trace the problem back to the transfer switch and was able to pick up a Go Power transfer switch from the nearest RV dealership 1.5 hrs away.
Definately thankful that I had the tools and knowledge to repair the trailer in the camp site. It otherwise would have been a quick end to our trip and probably an expensive repair at the dealership.

[Rlynxgolfer]

Thanks for the lead. Where would I locate the transfer switch. I would like to test.
Would I first put a load on inverter side outlet then unplug the shore power let it go
to inverted side off batteries. Wait a minute and then plug shore power back in to see
if it goes back to shore power. I am thinking now the power outage at night was so quick
that it did not allow the transfer switch to go back and stalled (open or closed) and kept
it on batteries?
Thanks again

[babock]

I agree that it's probably your transfer switch.

Why is the inverter even turned on while on shore power? Reason I ask is that even when an inverter does not have a load, it has a fairly high stand by current. I would see if there is a remote for your inverter to just turn it off while on shore power.

[tgold]

You should always use volt meter and test between hot neutral, hot and grounding(green or bare) and between two hots. You should get about 240 volts between two hots and about 120 volts between hot and neutral or ground. It is possible shore power had a failure and you only had one hot. Under certain conditions you may have gotten a backfeed reading showing 117 volts on each hot in the Rv. If normal now chalk it up as unexplained. I ave done electrical work since 74 and you cannot always explain what may have happen.

[Rlynxgolfer]

Good point, when I checked the voltage I had 117 volts Hot to neutral and ground on
both incoming legs.I did not check across the 2 phases reason being someone told me
they were both individual 110 volt legs with same potential another words 2 individual
110 volt legs not 240 volts between them. Will check next time plugged into 50 amp
service. But when plugged into 30 amp single phase outlet that service is split onto
both legs at only 110 volts so testing between both legs then you would get no reading.
So even if I had lost one of the legs on 50 amps 2 pole shouldn't the inverter picked up the one leg or maybe not because the plug adapter in 30 amp single phase does that for you. I too am a electrician but new too RVing and this buffalo's me need to understand.
Thanks and sorry for the long ramble

[cavie]

Originally Posted by Rlynxgolfer

Good point, when I checked the voltage I had 117 volts Hot to neutral and ground on
both incoming legs.I did not check across the 2 phases reason being someone told me
they were both individual 110 volt legs with same potential another words 2 individual
110 volt legs not 240 volts between them. Will check next time plugged into 50 amp
service. But when plugged into 30 amp single phase outlet that service is split onto
both legs at only 110 volts so testing between both legs then you would get no reading.
So even if I had lost one of the legs on 50 amps 2 pole shouldn't the inverter picked up the one leg or maybe not because the plug adapter in 30 amp single phase does that for you. I too am a electrician but new too RVing and this buffalo's me need to understand.
Thanks and sorry for the long ramble

You will, in fact, have 240 volts between the 2 phases BUT you can't use it in your coach. You have a split bus panel 50 amps on L1 and 50 amps on L2. That's 100 amps total. The main 50 amp breaker is the only one able to access both legs of the panel. When you plug into the 30 amp outlet you only get 1 leg. That one leg is then connected to both your busses. Do a search of the library

[cavie]

Originally Posted by Rlynxgolfer

Good point, when I checked the voltage I had 117 volts Hot to neutral and ground on
both incoming legs.I did not check across the 2 phases reason being someone told me
they were both individual 110 volt legs with same potential another words 2 individual
110 volt legs not 240 volts between them. Will check next time plugged into 50 amp
service. But when plugged into 30 amp single phase outlet that service is split onto
both legs at only 110 volts so testing between both legs then you would get no reading.
So even if I had lost one of the legs on 50 amps 2 pole shouldn't the inverter picked up the one leg or maybe not because the plug adapter in 30 amp single phase does that for you. I too am a electrician but new too RVing and this buffalo's me need to understand.
Thanks and sorry for the long ramble

I don't understand your "pick up one leg comment". From a 45 year Licensed Master Electrician


Generators
Conventional generators have a motor attached to an alternator that produces electricity. The motor must run at a constant speed usually, 3600 rpm to produce the standard frequency of 60 cycle current. If the engine’s rpm fluctuates, so will the frequency of electric output.

Inverters
A traditional inverter is powered by a 12 volt battery and produces 120v AC at limited wattage. No motor involved. Commonly used in Motorhomes and high-end 5th wheels.

Inverter Generators
These are motor driven 3-phase generators that output AC current like most traditional generators, but that current is then converted to DC, and then “inverted” back to clean AC power and frequency

They are called “inverter generators” but since people tend to simplify terminology, “inverter generator” often gets clipped, sometimes to “inverter” and sometimes to “generator” which leads to confusion as which one is being discussed. Both terms are commonly used to refer to inverter generators.

[Rlynxgolfer]

Thanks meaning of one leg ...was for some reason had only one leg of the two legs coming into Coach and when tested as you referred to back feed thru other leg to give
me the 117 volt reading on both never tested across both if I had and if that were the case the reading would be 0 volts.
We were at camp ground for 4 days again new to this RV. I am thinking we may have
Never had adequate shore power. We have 3 interstate cat.27--600CC--160RC batteries
i figure that is a total of 480 AH of battery power. I figure we used about 20 amps for
about 7 hours a night so if I a thinking right by the 4th night at 2 in the morning
The batteries reached there safe shutoff of 10.8 volts.
I know this sounds crazy but thinking of everything possible why the inverter shutdown
and of course would not start up because did not have both legs of the incoming power?
The plug we had plugged into had the hole face actually knocked off and even sparked
When plugged in the cords indicator lite was lite red so I thought all was good did not test.
Thanks for staying with me on this one

[formerFR]

I would assume, by your initial explanation, that you lost SHORE POWER during the night, causing your Inverter, which was 'ON', to start Inverting. With such a demand on the batteries from the high draw items you described as using, the Inverter would, at some point, shut Off(alarm, alert). This is to protect your batteries, and some inverters have a setting called LBCO(LowBatteryCutOut) that let's the user decide the Volts, such as 11.2, when the Inverter WILL shut down(cutout).

Now, why didn't your Transfer switch automatically set you back onto SHore Power when it was restored? That's a different device and a different question, but it could be coincidental that the power was only restored right before you went out to the Power pole to check it - the Inverter will sometimes need time before it automatically 'resets' itself.

To test your ATS(automatic transfer switch), unplug from Shore Power and allow the coach to use the Inverter. Then, start the generator, waiting for the 'clunk' sound saying that the ATS has worked, and the Generator has now taken over. Your Charger should now also be operational.
Again, stop the generator. The Inverter should come back into play, showing 'Inverting', if you have a readout panel. Go out and Plug the Shore Power cord back in. Wait for the 'clunk' from the ATS. If so, your ATS is good. If not, and the Inverter is still inverting, then your ATS could be to blame.

[formerFR]

... as for whether to keep your Inverter ON, or not, we've always kept it on as a back-up when Shore Power is lost, just as in your situation, though our LBCO setting will protect the batteries if shore power is lost too long. Now, our AGS(automatic generator starter) is set to kick on the generator to recharge the batteries well before the batteries would fall to such a low state. Generally, though, shore power is not lost long enough for this to happen, but it can, and has. The generator starting up in the wee hours of the morning while you are next to others in an rv park is quite startling, to say the least, but it's what the generator is for. And, it gives you a clue that something with the Shore Power is 'amiss'!

Also, check your shore power cord connection to the outlet itself, sometimes a 'not so tight' connection can be problematic, especially when you are using a lot of high draw items, such as heaters or air conditioners. Some power pole outlets have been used so often that they a 'loose' inside and don't make the best 'long term' connection.

[Rlynxgolfer]

I guess that was foolish to plug in but had no other choice and actually took something for granted which was not good. Learning the RV system which is good.
Thanks

[Rlynxgolfer]

Went back today a tested shorepower and generator ckts. All is working as required
It was just this 4 day outing that this has happened and had me puzzled.
Thanks

[Cypressloser]

Originally Posted by Rlynxgolfer

We have a 1000w inverter on our 2006 Dynamax Dynaquest 320.
Plugged into 50 amp service.During middle of night we were awakened with
Alarm of a safety shutdown of the inverter reaching 10.5 volts.
This is first time this has happened. When I checked it out the coach was still plugged in and showed both legs Hot into the panels main but no power on the
inverter side of the panel due to inverter shutdown.
Why would the inverter switch to battery inverter power when plugged into shore
power. Could we have lost shore power during the night,and why didn't the inverter go back to shore power when shore power came back on if that was the case? On the inverter side of the panel we had plugged in electric blanket, CPAC machine,
and phone charger and 1 IPad. so I guess that would take the battery down but
again we were on Shore Power.
All seems to be good now but always on my mind now.
What could have happened?
Thank you

I can see a number of potential issues here.
I realize your Dynamax is a 2006 but I don't know whether the inverter is a recent addition.

A) What is the distance between the batteries and the inverter?
I don't understand why the inverter in many installations is so far from the batteries and the wires so small causing votage drop of 10% or even 20%!!!

B) Check your inverter transfer switch and control board. They are known to fail, the question is not if but when.

C) Why is the inverter even on, or in standby mode when on shore power?

D) Check your setup and make sure you are not feeding 120 Volt electricity from the inverter back into the main panel and then have the converter/charger transforming it back into 12 DC power and attempting to recharge the batteries - yes, it is a possibility and it has happened.

Yeah, and check the Voltage between both legs (L1 and L2), it should be ~240 Volt or 120 Volt from L1 (L2) to Neutral and Ground.

[Rlynxgolfer]

Thanks have gone thru settings and all seem good. Cable sizing good.
Some say leave inverter on all time and some say turn off when not in use when on shorepower. I am in agreement with you why be on when not using inverted power.

[Cypressloser]

Originally Posted by Rlynxgolfer

Went back today a tested shorepower and generator ckts. All is working as required
It was just this 4 day outing that this has happened and had me puzzled.
Thanks

Maybe it was caused by a bad outlet on the pedestal but these kind of incidents can fry your electrical system. However, the inverter should have switched back to standby mode once the shore power was restored.
Do yourself a favor and invest in a decent EMS . I never trust campground power, one minute it is good and then the next it's crap.

[cavie]

Originally Posted by Cypressloser

I can see a number of potential issues here.
I realize your Dynamax is a 2006 but I don't know whether the inverter is a recent addition.

A) What is the distance between the batteries and the inverter?
I don't understand why the inverter in many installations is so far from the batteries and the wires so small causing votage drop of 10% or even 20%!!!

B) Check your inverter transfer switch and control board. They are known to fail, the question is not if but when.

C) Why is the inverter even on, or in standby mode when on shore power?

D) Check your setup and make sure you are not feeding 120 Volt electricity from the inverter back into the main panel and then have the converter/charger transforming it back into 12 DC power and attempting to recharge the batteries - yes, it is a possibility and it has happened.

Yeah, and check the Voltage between both legs (L1 and L2), it should be ~240 Volt or 120 Volt from L1 (L2) to Neutral and Ground.

When on shore power some inverters feed 1/2 of the split bus system. The inverter is always in operation. It supplies a limited amount of power.

[Rlynxgolfer]

Yes this coach has a split bus the inverter side has the microwave,bedroom and living
room outlets and TV.