Magnum inverter, Yamaha Generator

Hi happycamper002,

There is another thread that goes into this in greater detail.

It is true this issue has NOTHING to do with using an autoformer.

Load support offers blended power from shore power (or other source) and the hybrid inverter/charger.

Victron, Magnum and Outback offer this feature (there may be others). Xantrex has a similar feature but it switches the entire load to the inverter.

I've been using it successful since May of 2014.

Here is how it typically works.

I plug into a power source. I set the Magnum remote to the limit of that power source (say 15 amps). I turn on the inverter, to enable load support.

Let's say the water heater is on, (1200 watts or 10 amps) and I want to warm up a cup of coffee in the microwave (1591 watts or 13.26 amps)

But 10 plus 13.26 = 23.26 amps. The inverter takes the extra 8.26 amps from the battery bank and supplies it to the RV. Then when the load drops back down to 10 amps the charger portion of the Magnum recharges the battery bank.

BTW I am not the OP. GordonThree started this thread to help me investigate how the Magnum cooling system works, for which I have thanked him.

happycamper002 wrote:


The problem arose when OP tried to operate the inverter while the generator was still providing power to the bus. These two different power sources are jockeying for a place in the same bus. Someone will scream “there is a transfer switch to separate the two”.
Fine, but you still have shore power conductor that occupies a terminal in the transfer switch. You can have two but not three. (Inverter, Generator and Shore Power).

To prove the above statement OP said on this thread:

I shut down the inverter portion. (Obviously inverter was on )

Then I turned off the generator. (Obviously the generator was also running )

The Magnum remained connected to the battery bank. (Charging operation was still active. Charge current at 74 amps coming from converter. Where else would you get it from.)

This is what cooked your Magnum. Consider yourself lucky if your converter is still functional.

So, we can deduce from the evidence that OP was trying to operate both inverter and generator expecting a load sharing strategy. . . which I say, no possible way based on unsound practice that we've seen above.

However, all is not lost and OP's goal can still be accomplished, but it won't be easy and you can not unfry what's already fried.
Perhaps may even be more daunting for a simpleton like me. Cheers. :-)
Thanks for your time.