Pressure pump and Magnum 4448 causing washer shutdown

Dave Angelini

Subject:	This might help someone. I really have never seen anything like this with the equipment I use. Ever!

Hello Jeremy,

For more than a decade we have been aware of this issue wit Magnum Energy inverters. This primarily happened with the washer brand Splendide but other motors run by electronic controllers have caused the issue as well.  

When the washer is powered by Magnum inverters, the AC waveform becomes very distorted. You can view this on a scope as in the attached image. When you try to power other complex loads at the same time, the inverter can't sufficiently emulate a sine wave.

We found a simple solution. Install a high frequency inverter for the washer only. A 600W GoPower (made by Cotek) inverter has worked for us. They are cheap but well made with great support.

Magnum inverter running Splendide washer, Voltage(top) and current.

On May 26, 2021

Looking for recommendations on a solution for the following. 

Customer is doing laundry and when his new pressure pump comes on, it causes the normal power flicker, thus the washing machine shuts down. 

He runs a small generator to power the washing machine with no problems. 

The new pump is pulling from a cistern and is a 115V unit. Not sure of the pressure tank size or pump hp rating.

 

•ME 4448 PAE with one string of ~500 AH battery cap. 

BB.

Is the second smaller amplitude waveform the current flow?

If yes, it appears that the load has an AC full bridge rectifier on the input (normal for many AC to DC power supplies).

However in this case, it looks like one (or two) input diodes have failed open (left screen shows current bump) while the right side has no current bump (guessing this is current trace).

Of so, 1/2 wave rectification plays havoc with transformers... causes a DC bias current which can over heat the transformer and DC bias magnetic field saturate the transformer.

- Bill "pure guess" B.

Dave Angelini

I have no idea on which waveform is current. I just posted this because a colleague had the response from Magnum.
It looks to me like it is a case of we know there is a problem but we do not know/want to fix it. Totally goofy fix, to me!