Splendide washer on inverter - what works?

[drewke07]

We use a Splendide Washer / vented dryer combo with our Mastervolt Mass Combi 24/2500. Works like a charm unless we try to use the dryer. The units must be 20' apart.

[twistedtree]

Originally Posted by goboatingnow

little alarms bells should be going off in your head . beep beep beep......

it why the ferrites arent working , air coupled rf interference.
Dave

Yes, you may well be right. I'm trying to think back to all the experiments that I did last year when trying to diagnose this, wondering if I somehow ruled it out (incorrectly perhaps).

Since the thread has turned into diagnosing the problem, which is fine, I can add two other interesting tid bits.

1) If I run an extension cord and plug the washer into an inverter-powered outlet, kill shore/gen power so the inverter is the only source of AC, the washer runs fine.

2) If I leave the washed plugged into a shore/gen powered outlet, but open the breaker on the AC-in to the inverter, but leave the inverter running and powering it's AC loads from battery, it works fine.

I think these two things finalized my opinion that the noise was conducted via the AC-input on the inverter, not radiated. That said, the inverter could have a radiated noise pattern that's just enough different between operating in inverter-mode and operating in inverter/charger-mode that it triggers the problem. I'd also expect a fair amount of shielding of the washer electronics from its grounded, metal enclosure, wouldn't you?

Other than uninstalling the washer and moving it further away from the inverter, can you think of any test to confirm or rule out radiated noise?

[twistedtree]

Originally Posted by drewke07

We use a Splendide Washer / vented dryer combo with our Mastervolt Mass Combi 24/2500. Works like a charm unless we try to use the dryer. The units must be 20' apart.

Very interesting. I have a few follow up questions:

1) Where did the 20" separation figure come from? Mine are probably closer than that.

2) What's the problem if you try to use the dryer? Is it just too much load on the Inverter, or is there another problem?

3) Is your washer powered by the inverter Output, or is it only powered by shore or gen power?

4) Does the washer work equally well when you have shore or gen power and the inverter is in Charger-Mode?

Many thanks. Better understanding your setup and comparing it to mine might prove very useful.

[goboatingnow]

It sounds like an unloaded invertor is generating rf noise. This isn't unusual with poor inverter design. The boundary design issues can be quite difficult.

I'd still say its Rf coupled. ( do you have VHF interference

Dave

[Florida Mike]

If you think the inverter and washing machine is or to close I would first try wrapping the inverter in tinfoil. It shouldn’t overheat in the short time it would take to test for radiation. You might also try putting some chokes on a DC side of the inverter. It appears that the charger side of the inverter is dirty. I assume you have talked with the inverter manufacturers about this problem, if not give them a try.

What happens to run an extension cord to a inverter plug and leave the inverter running in its normal mode with external power your generator or short power applied? Just my two cents, Mike.

[twistedtree]

Originally Posted by goboatingnow

I'd still say its Rf coupled. ( do you have VHF interference

Dave

No, VHF is clear, and no signs of interference with anything else.

Just to be sure we are saying the same thing, you are talking about radiated emissions (transmitted through the air) as opposed to conducted emissions (transmitted through the wiring). You are not talking about any particular frequency band, right?

[goboatingnow]

Originally Posted by twistedtree

No, VHF is clear, and no signs of interference with anything else.

Just to be sure we are saying the same thing, you are talking about radiated emissions (transmitted through the air) as opposed to conducted emissions (transmitted through the wiring). You are not talking about any particular frequency band, right?

Correct though usually of there is radiated interference the harmonics sometimes give you interference on the VHF band. I would be deeply suspicious that it's mains wiring borne.

Try some temp shielding around the invertor , earth bonded aluminium foil etc as an experiment.

It's just the fact they are close and the problem is during an uploaded invertor operation. That's classic rf interference territory, some inverters have a power save cycle skip mode which can produce some bad interference if not properly choked out.

a scope would answer this fast

Dave

[FlyingCloud1937]

Originally Posted by FlyingCloud1937

Twisted,

I was referring to jay re: his trace.

Has your inspection been visual only, or are you using a MM to confirm isolation where required.

The only way to make an accurate survey is with a MM. make sure the S-N and the I-N are isolated. Also make sure your I-GSR is operating proper with the MM. Now with the shore circuit open, the gen circuit open, and the inverter circuit open, put the MM between N-N's and N-G, they all should show isolation.

Lloyd

Twisted, have you ever put a MM test as I outlined?

Try this link Ground Loop Noise

This might be more enlightening

Lloyd

[twistedtree]

Originally Posted by FlyingCloud1937

Twisted, have you ever put a MM test as I outlined?

Try this link Ground Loop Noise

This might be more enlightening

Lloyd

Thanks, and yes, I did probe it out. With the inverter off and the genset breaker open, N-G is open (actually about a mega ohm which I think are GFIs?), and N-N is open as well between the two bus bars. So as best I can tell it's working correctly.

To have a ground loop, I would have multiple points where neutral is tied back to ground, right? Is there some other scenario I should be looking for?

And with things running and powered up, how much voltage (mV) should I see between neutral and ground before the alarms should go off? I might be able to do some more measuring tomorrow.

Thanks for the ideas.

[FlyingCloud1937]

twisted,

I have one other simple test for you to try.

While connected to shore power, and that breaker closed, go to the inverter control panel, and manually put it in to stand-by mode. Then try to run the washer.

What this should accomplish is forcing the automatic GSR to open on the inverter.

I still want to make sure the GSR is operating properly.

Lloyd

[FlyingCloud1937]

Originally Posted by FlyingCloud1937

twisted,

I have one other simple test for you to try.

While connected to shore power, and that breaker closed, go to the inverter control panel, and manually put it in to stand-by mode. Then try to run the washer.

What this should accomplish is forcing the automatic GSR to open on the inverter.

I still want to make sure the GSR is operating properly.

Lloyd

Ok Twisted,

I just reviewed the mastervolt site and schematics, I don't find any that show a Automatic GSR.

So if this is how your unit is connected then Huston we have a problem.



All of the matervolt scmemas show a bond between N-G at the inverter, then a RCB at the panel on the inverter out.

I think you have a classic case of N-G circulating currents.

Please confirm that you have an actual Automatic GSR, or the hook up as the manual demonstrates.

If your hook up is, as the manual shows, let me know bc I can give you the part numbers and a schematic to create a A-GSR for $50.00 in parts from Grainger.

Lloyd

[FlyingCloud1937]

Originally Posted by FlyingCloud1937

Ok Twisted,

I just reviewed the mastervolt site and schematics, I don't find any that show a Automatic GSR.

So if this is how your unit is connected then Huston we have a problem.



All of the matervolt scmemas show a bond between N-G at the inverter, then a RCB at the panel on the inverter out.

I think you have a classic case of N-G circulating currents.

Please confirm that you have an actual Automatic GSR, or the hook up as the manual demonstrates.

If your hook up is, as the manual shows, let me know bc I can give you the part numbers and a schematic to create a A-GSR for $50.00 in parts from Grainger.

Lloyd

Automatic GSR Issues

[goboatingnow]

The simple test for earth faults or ground loops is to temporarily disconnect grounds from the inverter and the washing machine , test for hot case with multimeter or back of hand! . It will show up faults but I don't suspect it's a ground fault or loop

Dave

[twistedtree]

Originally Posted by FlyingCloud1937

Ok Twisted,

I just reviewed the mastervolt site and schematics, I don't find any that show a Automatic GSR.

So if this is how your unit is connected then Huston we have a problem.



All of the matervolt scmemas show a bond between N-G at the inverter, then a RCB at the panel on the inverter out.

I think you have a classic case of N-G circulating currents.

Please confirm that you have an actual Automatic GSR, or the hook up as the manual demonstrates.

If your hook up is, as the manual shows, let me know bc I can give you the part numbers and a schematic to create a A-GSR for $50.00 in parts from Grainger.

Lloyd

Lloyd, thanks again for digging in so deeply. It's forcing me to re-check my checks which is always good.

The Matervolt device I have is the MassCombi 12/2500. The schematics in the manual suck, showing neither the double-pole AC passthrough that breaks both L and N, nor the GSR. But the tabular spec sheet calls out the double-pole relay (without saying what it accomplishes) and I have confirmed via MM that the neutrals switch along with L. And when you read about all the configuration options controlled by the 2 DIP switch packs, one of them controls the N-G relay, and is normally disabled. I have it enabled, and again have confirmed that N-G is isolated when the Inverter is off, and bonded when it's on and AC input is not present. None of this is reflected in the schematics which is unfortunate.

I think this boat may be one of the rare cases where all the ground-neutral bonding has actually been done correctly.