question

manhard avatar image

Quattro and multiplus in offgrid making a loud buzzing noise and generator roughing

Here is the topic, i have builded and installed many system since i began working with victron products, it's the first time that i see this kind of trouble.


My system is builded on a sheet of aluminum 1/8 thickness where everything is located on it as: quattro, lynx bus system and distributor bars, solar MPPT 250/100, aux. centaur charger 24/60, AC main panel, ccgx and wiring cleanly strapped, not the first like that and they all juste work roundly all the time.

System work's fine for the most part, everything is stable and silent unless i hook up a generator to this offgrid system, in my shop when i tested on my test bench i heard no noise or harshness from the inverter when i hooked it up to the grid to charge my testing battery bank but at the customer place oh boy!

so when it's hooked up (brand new honda eg5000cl) the inverter already start humming a bit then when the charger ramp up to max output it is very concerning like a rattle humming noise unequal making the generator sometime lead to disconnection temporarily and reconexion after 1-2 min.

Even when i totally isolate the AC panel from the inverter by flipping the main AC breake i still have this bad noise so i don't think it is comming from AC directly, i found some ground/neutral loop in this house that i immediatly solved to clear few trouble makers but the only way to tame the noise is to isolate the battery bank from the quattro charger it return to a normal noise.

I stabbed a 10 foot ground rod near the generator and hooked up to the house ground rod to help draining any noise directly out of the generator but it gives nothing.

i tryed a dummy battery bank with 4 Rolls S-550 PBA battery instead of connectiong it to the large rolls 2ks 1866ah bank that already ave 5 years but it's the same problem so it's not the battery.

i tryed many ground to neutral placement in the electrical panel( bonded to neutral or direct to frame and insulated from neutral) just to check but nothing helped, my generator is connected to input 1 since i don't have grid there, i tryed with a multiplus just before because my customer was in trouble and needed a system ASAP and it was even worse so it's not the inverter directly.

Something i noticed from the generator was when it ramp up to the charger max power output it will give the hiccups to my generator even if we are only loaded at 21A/30A AC i can hear my generator in the inverter and also the hiccups happening randomly.

it should be pretty silent normally so im mesmerized what it could be when it's working great in my shop, i heard NE relay chatter could cause a rattle hum noise, would it be that loud and accentuating with load? if so why? and is it a good option to just manually toggle the NE ground relay in the software if my main neutral ground bound is in the main AC panel and that the sheet itself serve here as a common ground/heat spreader/frame bonding everything.

Could it be my aluminum sheet magnetically vibrating because of the inverter high power output? if so i would feel it in the wall and the generator would not throbble like that!

well im rubbing my head like a monkey there let me know your tought! i can acces the system via VRM if needed to test thing remotely or go on site if i have good cues, my next step was to swap with a different generator like a yamaha 7200 and run a new ac cable from the gen if it was doing nothing more to help.

MultiPlus Quattro Inverter ChargerGeneratoroffgrid
2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
Andrew Jefferies avatar image
Andrew Jefferies answered ·

Have you / are you able to check or adjust the stability control on the AVR ? I don't know the gen but I noticed bad noise from my setup once. Stability / response time was too short causing very rapid under/ over voltage cycling on gen output

2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

manhard avatar image
manhard answered ·

Your right i learned allot from this particular project the thing is my customer already had it and we have way to reduce the load on the generator so i believed there would then be no problem using a smaller one, the book state at leadt 8kva gen so i will reduce the output of 30% it should help that generator

2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

manhard avatar image
manhard answered ·

That is a good question, i didn’t know we could adjust the AVR, i will forsee this in my next visit, the generator is a brand new honda EG5000CL

1 comment
2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Just looked at a pic of the Gen. Humm I doubt if you can adjust as its probably regulated, not very well, by capacitors.

I assume this 110V AC as 30A @ 230V would overload the gen !

Personally it is not the type of generator that I would have chosen..