wierd Inverter configuration...

Thread Starter

mitchsten443

Joined Jan 20, 2020
4
I bought a full sine wave inverter from china made by "Advanced". Now before you start saying things like "figures", what did you expect, etc etc..
I owned a 2K one of thiers which has run for 24/7 for over 4 years now with zero problems. I was averaging 300watts continuos and peaking at 1500 for no more then 15 minutes at a time. it runs my gas dryer, washing machine, dish washer, refridgerator, deck lighting a 42 in lcd tv, fios box, laptop and several phone chargers..

Anyway with the purchase of a new frdige (much bigger) and new washer/dryer also much bigger we needed more the 2K so I bought a 5K..

all that stuff works fantastic, except:
When charging phones and the lap top the touch screens would randomly press in places we didn't touch, every once in a while the ryer would say the door is open when it clearly was closed and the switch was shorted.. And every so often the washing machine would just lock up.

So I tested the inverter, I get a great pure sine wave even under heavy load, the total voltage never drops below 112v and never goes over 118v mostly sits at 115v-116v.

So I went to test for "noise" by testing voltage between the nutral and ground.. low and behold I got 65v! then between the hot and ground I got 65v. between the hot and nuetral (white) I get the 115-166...

I never saw this before, the 2k one delivers 115v between hot (blk) and nuetral (wht) and also 115v between hot and groun and zero betwen nutral and ground..

What can I do to get 115v from the blk and zero from the white... like it should be.

It was told to me by someone who claims to be an engineer that the inverter is actually 2 2500watt inverters at 65v. 65 on the blk and 65 on the wht, the way a standard 240v system would be setup.. But I figure there has to be a way to combine the two and then use the ground as nutral..
 

crutschow

Joined Mar 14, 2008
34,452
You'd have to get a schematic of he inverter to see if it can be connected with the neutral to ground, as it should be.

What powers the inverter?
 

Rich2

Joined Mar 3, 2014
254
I think you will need a 1:1 isolation transformer. In other words bin the inverter and spend a bit more on a good one.
 

Thread Starter

mitchsten443

Joined Jan 20, 2020
4
I think you will need a 1:1 isolation transformer. In other words bin the inverter and spend a bit more on a good one.
I sent the inverter back, got a new one and the problem is resolved. There was 15-65v of "noise" between the ground and nuetral.

As I said the company oes make good inverters, I ran the 2000 watt one for over 3 years, and it is still running at someone elses house.

What I really need is a decent tester, or at least one that let's me know the battery is going dead instead of just reading 65 volts when there is 120v and reading 65volts when there is 15v... lol... before you say get a better battery it was a duracell...
 

BobaMosfet

Joined Jul 1, 2009
2,113
I sent the inverter back, got a new one and the problem is resolved. There was 15-65v of "noise" between the ground and nuetral.

As I said the company oes make good inverters, I ran the 2000 watt one for over 3 years, and it is still running at someone elses house.

What I really need is a decent tester, or at least one that let's me know the battery is going dead instead of just reading 65 volts when there is 120v and reading 65volts when there is 15v... lol... before you say get a better battery it was a duracell...
You should never see much (if any) voltage between neutral & ground (This aka 'IR Drop' is caused by load current flowing through the impedance of the white/neutral wire). If you do, you have something (in your case, it looks like it was the inverter itself, as you replaced it and fixed the problem) dumping to ground incorrectly, and this also creates a floating ground.
 
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