just fried my computer connecting to the USB port on a MPP controller . . .110v to the usb from a 220 inverter . . .how is this possible?

Go2Guy

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Feb 15, 2021
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the problem. when ever the mpp is on bypass mode there is no voltage on ground BUT when ever the inverter actually starts inverting power, there is 110 v in reference from the ground lug on the mpp and to the actual ground. . i am so puzzled. I was still in process of trying to diagnose this issue and had my pc connected to the USB port of the MPP and when made a change to SBU and solar priority. the second i saved the settings it instantly switched from bypass mode to inverter mode and boom, the whole dam USB cable fried and my computer INSTANTLY SHUT OFF. . . im am extremely saddened by this, luckily my drives were not damaged .. but just cant figure this out. .
This is the set up

[ i have to 2 main panels [I call them both main because they are both directly wired to the 220 main breaker outside the house and our independent of each other aka not a sub panel of the other] the newer main panel houses all the 220 devices which were moved over to it [ac , water heater etc] and the other main panel was the original panel houses the rest of the house, so the 220 only panel stays live and feed the mpp and AC while the original main panels main breaker is shut down and back fed thru the 30 amp genertor interlock. [we will call the new panel the "220 panel" and the original the original panel] both main panels have there own main breaker, are grounded to each other and carry the same neatrual [the main breaker on both of these units do not disconected the neutral]

so i have a PIP2424HSE 220v model.I have 220 coming into the unit from 220 panel] and the 220 output of the mpp connected to a power jack split phase transformer 3000w transformer . i have the L1 L2 N of the transformer wired in a 30 amp generator interlock breaker on the main panel panel . .
some side notes, when i first set the unit up I grounded everything [ground from 220 panel, to the mpp, ground from mpp frame lug to frame of transformer, and ground from the frame of transformer back to original panel. . . when inverter was on bypass mode there was no issues, but the second it went into inverter mode and it shut down and error[I thought i fried it. . . I disconnected the all grounds and it worked flawlessly, the whole house was powered with split phase 220. . . BUT just as quick test, I very quickly and lightly tapped the ground from the main panel to the ground lug on the mpp it gave a big spark this is when i new there was an issue with voltage with reference ground. . . i just dont understand how. . . if all the ground are disconnected how the hell is the 110 coming out of the ground on the mpp when 110 is not even connected to the unit the 220 comes in and 220 comes out and 110 never goes into the unit. even when the 220 in is disconnected issue still persist . as a test I held a probe of a multimeter on voltage mode and touched the the other probe to the ground lug on the mpp frame and sure enought 110 volts in reference to me aka earth ground to mpp frame ground. . . so the question is where is it coming from , and how is getting there. . . and also remember when unit goes to bypass mode the issue disappears while the transformer is still working in converting the 220 only its receiving into 110 split phase.


here all the tests I did. . .
set to bypass mode, issue disappears
Disconnected the 220 input to unit, issue still persist
disconnected transformer issue disappears
connected transformer BUT disconnected from transformer from house, issue disapears, this shows its not the transformer
shut off 30 amp breaker in original panel and but still had it connected to that breaker issue is still there
tried reversing the the hot and neutral from the out of the mpp to the transformer and it made no difference, issue still there

its seems that the bond between the neutral and and ground in the panel is the culprit BUT it still does not explain how when all grounds are disconnected from the set up[mpp and transformer], how 110 is making its way up backwards through the 220 output of the mpp and manifesting its self in the frame of the unit. not only that i was under the impression that these unit were designed to be connected to bonded neutrals . . also if there was some type of short would the unit read 220 in reference to ground not 110. . . . . it just makes no sense,


I would greatly apprecate any assitance
 

Joe BoyKey

Watts, Watts, more Watts
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Messages
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Location
Austin Texas
What type of transformer - Isolated or AutoTap, I started out with a MPP solar 5048 (230v euro) and tried to run through a 500w transformer and blew it up, Seller took it back and sold me a SPF-6000T-DVM which has a built in ISOLATED transformer, problem solved. In the process I learned the difference in transformers and found out what happened in this article, (https://www.gson.org/stepdown/) searched my circuits and found an old Surge arrester to my electronic freezer that was burnt to a crisp but still putting out ac. Horrible experience because MPP sent me another Power board and it worked for a while since the Surge arrester had opened up short to ground. Also you must have L1, L2, Neutral and Ground from House panel with the Neutral to Ground bond at house panel and only there, not at any sub panels - Single point Neutral to Ground PERIOD. Had to rewire panels for lower voltage but am very happy with Growatt, Read the article and be careful with the A/C, Joe.

AutoTap 1619034500468.png


Isolated 1619035356656.png
 

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Go2Guy

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Feb 15, 2021
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the neutral is bonded out side near the main breaker. . . the original panel on the inside did not have a main breaker, I installed main breaker on that panel for the sole purpose to shut it off to use the generator interlock and back feed that main panel, to think of it a different way the main breaker is outside which feeds the main panel inside that had no main breaker, What i did was install a double tap lug1619036210804.pngThis allows me to to tap into the main from outside with out going thru a breaker on the original panel. and have a second main panel that is independent from the first pain panel, as you posted the there is a common ground and common neutral between the 2 panels.
the goal was so that the original panel with most the loads be fed by solar, and all the high power 5000 watt plus 220 devices ac, heater, welder etc be moved to be kept on grid. . . the only 220 left on the original panel was the stove, as i grow my stytem to be more power full I will move more 220 devices back over, but the the stove only uses 1500 watts with 1 burner and 2200 watts in the oven.so its useable as of right now. . .[ actually plan on testing several different units
This is the transfermer.https://www.ebay.com/c/23021290743 . I am not sure if it is an isolated type or not. . whats really weird tho is when the unit goes into bypass mode, and feeds 220 only [no neutral] to the transformer it reconverts that 220 into split phase with no issues. . . I just dont understand how 110 can back feed thru and 220 inverter output and manifest its self on the inverter case ground when there is no ground hooked hook to the inverter[i mentioned why in the original post.] it just makes no sense.
 

Go2Guy

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20210421_163231.jpg
 

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Go2Guy

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Feb 15, 2021
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I figured it out as to what was occurring. . its a brain buster to figure out but seems to be spot on. . . the inverter has a 220 hot and neutral. the inverters neutral is bonded to the case of the frame. . . the power jack auto transformer takes the neutral and makes it a hot 110. . essentially they are purposely using the transformer in sort of reverse to get split phase, so instead of keeping the neutral the same from the input and output they are making the inverter neutral a 110 on the transformer. .. . . this works great if the system is floating but once it is connected to a main panel which is has its neutral bonded to earth everything changes. . . whats happening if you look at the picture and writing i did on the the transformer which shows a rough schematic: is the the Neutral out put of the transformer to the neutral of the inverter now makes 110, the problem is that the frame of the inverter is bonded to the neutral so the frame of the inverter is also 110, so to summarize this madness. you get a voltage potential of 110 volts from neutral and ground of the inverter case to actual real earth ground that your are standing on, this also means you get zapped if you touch it [got zapped like 5 times accidently trying to figure what was going on]. . . this is also what fried my PC. . . the ground of the inverter which is also connected to the usb ground is now 110 to earth so when I connnected it to my pc usb which is actually ground to earth ground I litterly shot 110v straight into the USB mother board, and instantly toasted it . . . powerjack should be sued for this and they owe me a pc, they litteraly advertise this as an transformer for inverter use and make no mention of this issue with inverters that have a bonded neutral 1619889766192.png
 

x4dow

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Dec 30, 2020
Messages
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I figured it out as to what was occurring. . its a brain buster to figure out but seems to be spot on. . . the inverter has a 220 hot and neutral. the inverters neutral is bonded to the case of the frame. . . the power jack auto transformer takes the neutral and makes it a hot 110. . essentially they are purposely using the transformer in sort of reverse to get split phase, so instead of keeping the neutral the same from the input and output they are making the inverter neutral a 110 on the transformer. .. . . this works great if the system is floating but once it is connected to a main panel which is has its neutral bonded to earth everything changes. . . whats happening if you look at the picture and writing i did on the the transformer which shows a rough schematic: is the the Neutral out put of the transformer to the neutral of the inverter now makes 110, the problem is that the frame of the inverter is bonded to the neutral so the frame of the inverter is also 110, so to summarize this madness. you get a voltage potential of 110 volts from neutral and ground of the inverter case to actual real earth ground that your are standing on, this also means you get zapped if you touch it [got zapped like 5 times accidently trying to figure what was going on]. . . this is also what fried my PC. . . the ground of the inverter which is also connected to the usb ground is now 110 to earth so when I connnected it to my pc usb which is actually ground to earth ground I litterly shot 110v straight into the USB mother board, and instantly toasted it . . . powerjack should be sued for this and they owe me a pc, they litteraly advertise this as an transformer for inverter use and make no mention of this issue with inverters that have a bonded neutral View attachment 47405
no1 is gonna comment how he has a nazi inverter?
 

Sanwizard

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Feb 2, 2021
Messages
1,353
I figured it out as to what was occurring. . its a brain buster to figure out but seems to be spot on. . . the inverter has a 220 hot and neutral. the inverters neutral is bonded to the case of the frame. . . the power jack auto transformer takes the neutral and makes it a hot 110. . essentially they are purposely using the transformer in sort of reverse to get split phase, so instead of keeping the neutral the same from the input and output they are making the inverter neutral a 110 on the transformer. .. . . this works great if the system is floating but once it is connected to a main panel which is has its neutral bonded to earth everything changes. . . whats happening if you look at the picture and writing i did on the the transformer which shows a rough schematic: is the the Neutral out put of the transformer to the neutral of the inverter now makes 110, the problem is that the frame of the inverter is bonded to the neutral so the frame of the inverter is also 110, so to summarize this madness. you get a voltage potential of 110 volts from neutral and ground of the inverter case to actual real earth ground that your are standing on, this also means you get zapped if you touch it [got zapped like 5 times accidently trying to figure what was going on]. . . this is also what fried my PC. . . the ground of the inverter which is also connected to the usb ground is now 110 to earth so when I connnected it to my pc usb which is actually ground to earth ground I litterly shot 110v straight into the USB mother board, and instantly toasted it . . . powerjack should be sued for this and they owe me a pc, they litteraly advertise this as an transformer for inverter use and make no mention of this issue with inverters that have a bonded neutral View attachment 47405
And whats with all the backwards Nazi symbols on the frame?
 

LB3

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Sep 12, 2020
Messages
102
no1 is gonna comment how he has a nazi inverter?
It’s a common symbol in Asian religions such as Buddhism and Hindu religions.

Pokémon cards sold in Asia have these symbols as well.
 

Woody

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Dec 13, 2020
Messages
133
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Technically that’s the running logs / good luck symbol. Many cultures have used this symbol long before the Nazis used one similar to it. Google it and you can see the confusion/differences.
 

bgflyguy

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Jul 8, 2020
Messages
139
Is this the 220v international mpp vs the split phase? I was confused by the similar models.
 

Joe BoyKey

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@bgflyguy Split phase is US 220v - 2-110v out of phase circuits
International is 220v single phase, no 110v without an additional transformer, GO Split Phase in USA, Joe.
International Charge controllers usually have higher Voc inputs from panels, Split phase uses lower.
 
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Mahendra Gomanie

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Mar 8, 2021
Messages
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I figured it out as to what was occurring. . its a brain buster to figure out but seems to be spot on. . . the inverter has a 220 hot and neutral. the inverters neutral is bonded to the case of the frame. . . the power jack auto transformer takes the neutral and makes it a hot 110. . essentially they are purposely using the transformer in sort of reverse to get split phase, so instead of keeping the neutral the same from the input and output they are making the inverter neutral a 110 on the transformer. .. . . this works great if the system is floating but once it is connected to a main panel which is has its neutral bonded to earth everything changes. . . whats happening if you look at the picture and writing i did on the the transformer which shows a rough schematic: is the the Neutral out put of the transformer to the neutral of the inverter now makes 110, the problem is that the frame of the inverter is bonded to the neutral so the frame of the inverter is also 110, so to summarize this madness. you get a voltage potential of 110 volts from neutral and ground of the inverter case to actual real earth ground that your are standing on, this also means you get zapped if you touch it [got zapped like 5 times accidently trying to figure what was going on]. . . this is also what fried my PC. . . the ground of the inverter which is also connected to the usb ground is now 110 to earth so when I connnected it to my pc usb which is actually ground to earth ground I litterly shot 110v straight into the USB mother board, and instantly toasted it . . . powerjack should be sued for this and they owe me a pc, they litteraly advertise this as an transformer for inverter use and make no mention of this issue with inverters that have a bonded neutral View attachment 47405
I was raising.this exact.same issue in another thread.
What did you do to get this sorted ?
 

Tecnodave

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Mar 22, 2021
Messages
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@bgflyguy Split phase is US 220v - 2-110v out of phase circuits
International is 220v single phase, no 110v without an additional transformer, GO Split Phase in USA, Joe.
International Charge controllers usually have higher Voc inputs from panels, Split phase uses lower.
In reality USA grid is 120/240 volts, appliances that use this grid are rated for a minimum voltage of 110 volts or 220 volts to allow for voltage droop under load

In europe the grid is 230 volts with the appliances rated for a minimum of 220 volts....same reason

My local utility PG&E often runs at 125/250 volts, it allows for greater loading of our grid as PG&E is about 50 late in grid upgrades.

They are so bad that the linemen have renamed the company as Pigs, Goats and Elephants
 

Tecnodave

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Mar 22, 2021
Messages
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This whole issue is exactly why it is a very bad idea to use equipment meant for one grid then hacking in a transformer to make it work on a grid it was not designed for.

Its not acceptable to the NEC or any other code set here in the US

Also not acceptable to your insurance company, If they find that in the burned down embers that was your house you have just handed them a get out of jail card! , they have no obligation to pay you any damages!
 
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