I have a 3 year old Coach with the above system. It’s monitored/controlled by a Firefly system, thus, no Magnum Energy Remote Controller which I hate. Inverter works going down the road, and Charger works if I happen to run the Generator. When I arrive at my destination, and plug into shore power, the system goes into Passthru mode, as it should, thus enabling charging/passthru power. Unfortunately it only stays on for 2 minutes before disabling all passthru power and charging. I can get it back on, if I shut off the pedestal, battery disconnects and then bring it back online. It will stay up and running if I disable the charge side, or the passthru side, but not both. When it does shut itself off, it goes from its standard 117-122 volts coming in, to showing 181 volts coming in. I’m sure this is a fantom reading, but what’s causing it. I have been at multiple parks, so different pedestals. I also use a Hughes Bulldog surge protector on Bluetooth so incoming power is not the issue.I have spoken with Firefly and Magnum and we’ve tried different things with little change. Connections are all good, I’ve tested the battery bank (individual batteries) and all good. We have also unplugged the bridge between the Firefly and Magnum, thus taking the Firefly out of play, and no change.Anybody else run across this type of problem.TIAScott

Transfer switch letting some through so you see 181 volts (at least not 240! ) ?

Hi,What happens if you remove the bull dog unit? Measure the pedestal voltage. It may be there is a failed neutral on the pedestal.

pianotuna wrote:Hi,What happens if you remove the bull dog unit? Measure the pedestal voltage. It may be there is a failed neutral on the pedestal.3 different parks now, all with good power both with and without the Bulldog. All voltage at each location was within range. Even watched it for fluctuation, boy that was fun.

BFL13 wrote:Transfer switch letting some through so you see 181 volts (at least not 240! ) ?I really think this is some fantom reading because it’s the same each time and at different parks/pedestals. I don’t see this when the generator is running. I suppose the transfer switch on the park power side could be going bad and reading 181, but I’d assume it would vary in the numbers. Not sure.

When using the genny, the inverter also goes into the pass-thru mode (as it does with shore power), but if I understand correctly, there appears to be no problem with the generator as the power source…IF so, then the problem seems related only to the shore power source…Note that both the surge guard and/or the inverter have the ability to either qualify OR reject the incoming AC power, and for some reason (possibly the shore power cord??) your set-up is qualifying only the generator..My guess is that the generator does not pass-thru the surge guard, which may point to the surge guard…I had a similar problem whereby my pass-thru Prosine 2.0 would reject Genny power when I tried to run the Honda in the eco mode, however, the Inverter would qualify the generator when not in the eco mode…Pass-thru inverters can sometimes be fussy in this way…3 tons

Magnum MS 2812 Charger/Inverter Issue | Good Sam Community

3_tons
Explorer III
Oct 20, 2021
“ Power comes thru for non-inverter circuits every time on shore power. No issues with that. ”

What are your inverter circuits?…Maybe it’s the pass-thru ATS switch that’s built into the inverter?

3 tons
strudeau
Explorer
Oct 20, 2021
rdhetrick wrote:
strudeau wrote:

why do I still get power to my non-inverter circuits such as washer/dryer and AIr Conditioners?

Do you have power to these all the time when on shore power? Or only initially?

Like I said, on mine, the hot relay shorted - essentially the hot leads from the shore power were connected to the hot leads from the generator power.

When power is applied from the generator side, the delay is initiated then the neutral relay switches over to the generator neutral - everything is happy and works.

When power is applied from the shore side, the delay is initiated then the neutral relay switches over to the generator neutral - now the hot and neutral is not matched and the problem occurs. All power is lost and the inverter thinks it's not connected to anything and turns on supplying power from the batteries. When it does this, the neutral relay drops back to shore neutral and now there is matched power in the hot and neutral supplies starting the cycle again.

This may not be what is happening in your case, but if you notice the inverter/charger continually cycling, I bet it's something similar.

If you know where your transfer switch is, open the cover and inspect the relays, you'll notice signs of overheating if this is your problem.

One of the first things I did. All Transfer switch wiring is perfect and torque is as well.

Power comes thru for non-inverter circuits every time on shore power. No issues with that.
rdhetrick
Explorer
Oct 20, 2021
strudeau wrote:

why do I still get power to my non-inverter circuits such as washer/dryer and AIr Conditioners?

Do you have power to these all the time when on shore power? Or only initially?

Like I said, on mine, the hot relay shorted - essentially the hot leads from the shore power were connected to the hot leads from the generator power.

When power is applied from the generator side, the delay is initiated then the neutral relay switches over to the generator neutral - everything is happy and works.

When power is applied from the shore side, the delay is initiated then the neutral relay switches over to the generator neutral - now the hot and neutral is not matched and the problem occurs. All power is lost and the inverter thinks it's not connected to anything and turns on supplying power from the batteries. When it does this, the neutral relay drops back to shore neutral and now there is matched power in the hot and neutral supplies starting the cycle again.

This may not be what is happening in your case, but if you notice the inverter/charger continually cycling, I bet it's something similar.

If you know where your transfer switch is, open the cover and inspect the relays, you'll notice signs of overheating if this is your problem.
strudeau
Explorer
Oct 20, 2021
rdhetrick wrote:
Most likely the hot relay in the transfer switch. I just had to replace mine, very similar situation - when plugging into shore power, I had power for 30 seconds, then lost it.

In my transfer switch, there is a 30 second delay in the neutral relay to give the generator to come up to speed before transferring the full load. The hot relay was shorted so when applying shore power, it triggered the 30 sec delay. During this delay, everything worked, but as soon as the neutral relay switched, shore power was lost.

Replaced the relay and all is good now.

Not sure if this is it or not as the power travels from shore connect, to transfer switch, to main panel, to Charger/inverter. If I have a transfer switch issue, why do I still get power to my non-inverter circuits such as washer/dryer and AIr Conditioners?
rdhetrick
Explorer
Oct 20, 2021
Most likely the hot relay in the transfer switch. I just had to replace mine, very similar situation - when plugging into shore power, I had power for 30 seconds, then lost it.

In my transfer switch, there is a 30 second delay in the neutral relay to give the generator to come up to speed before transferring the full load. The hot relay was shorted so when applying shore power, it triggered the 30 sec delay. During this delay, everything worked, but as soon as the neutral relay switched, shore power was lost.

Replaced the relay and all is good now.
3_tons
Explorer III
Oct 20, 2021
Using a volt-ohm meter, check for continuity issues between the cord’s male end (4 post) and at the surge-guards input side with cord unplugged…Then, if cord proves ok, plug in cord (pedestal breakers ON), and verify surge-guard input taps, i.e. 120v to neutral, and 120v to neutral, then compare this finding with the output taps…

3 tons
Gdetrailer
Explorer III
Oct 20, 2021
strudeau wrote:
Update: All connections in the Surge Guard Transfer switch are good and torqued appropriately. Connection/hot/common/ground in main panel all good.

Decided to bring the system online slowly by shutting off all incoming power (breakers) and main 50amp. Turned on the breakers 30 amp for the inverter and then one circuit and I got inverter power. Waited, and brought all inverter circuits up, and all was well.

Next I turned all the circuits back off and then turned the 50amp back on at the pedestal. I have two 30 amp breakers labeled charge #1 and charge #2. I monitored my read outs on my Firefly /Vega Touch specific to the Magnum. When I turned on charger #1 it showed zero on the AC Input Volts. When I turned on charger #2, it initially showed AC input volts at 118, and that the charger had come on (float). After 45 seconds, it kicked off and my AC input showed 184 volts as it has in the past.

I tested both 30 amp breakers on the meter and they both are good.

I’m down to the shore power cord at this point, unless anybody has other ideas.

Thanks again
Scott

Try taking a reading of the voltages with a separate volt meter like a DVM.

If the separate DVM does not read the same voltage as your display when the fault happens then the issue is with your inverter/charger.

If separate DVM reads the same as your display (181V) then issue most likely is the shore cord connection (adapters?).

Personally, if the shore power cable is at fault, it should not take 45 seconds for the system to fail, it should be immediate shut down.. Pointing a lot closer to a failure of your inverter/charger..
strudeau
Explorer
Oct 20, 2021
Update: All connections in the Surge Guard Transfer switch are good and torqued appropriately. Connection/hot/common/ground in main panel all good.

Decided to bring the system online slowly by shutting off all incoming power (breakers) and main 50amp. Turned on the breakers 30 amp for the inverter and then one circuit and I got inverter power. Waited, and brought all inverter circuits up, and all was well.

Next I turned all the circuits back off and then turned the 50amp back on at the pedestal. I have two 30 amp breakers labeled charge #1 and charge #2. I monitored my read outs on my Firefly /Vega Touch specific to the Magnum. When I turned on charger #1 it showed zero on the AC Input Volts. When I turned on charger #2, it initially showed AC input volts at 118, and that the charger had come on (float). After 45 seconds, it kicked off and my AC input showed 184 volts as it has in the past.

I tested both 30 amp breakers on the meter and they both are good.

I’m down to the shore power cord at this point, unless anybody has other ideas.

Thanks again
Scott
wolfe10
Explorer
Oct 20, 2021
byronlj wrote:
Check your neutral connection in your original breaker box where shore cable is attached. I bet it is loose.

Yup, 180 VAC means you are loosing the NEUTRAL somewhere.

If it has happened in multiple parks, highly likely it is a connection in your shore power cord or coach wiring, ATS or breaker box.
byronlj
Explorer
Oct 20, 2021
Check your neutral connection in your original breaker box where shore cable is attached. I bet it is loose.

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