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EG4 18KPV - What not to do in parallel

ksmithaz1 said:
!This is not accurate! The person who installed did not follow all the procedures in the manual and did not use the factory provided cable which is clearly labeled. The manual has no specifics listed on the interconnect cable, thus unlike *ME* the installer did not verify the cable pinout before substituting it with a different cable. Since the installer decided to use some random ethernet cable that happened to be a crossover it created an unusual fault condition that was not detected by the firmware, nor anticipated by the manufacturer. I would hold a manufacturer liable if they don't correct the documentation with a warning once they see the deficiency. If possible I expect a firmware or simple hardware fix to prevent this condition as quickly as possible now that the problem is identified. I would expect future revisions of the product to not allow this behavior.

If someone accidentally mis-wires something I built and it causes a problem I'm not the one who screwed up. Not too long ago, I inadvertently plugged a 110v/220v power supply into a 220 without moving the physical switch. I got magic smoke it blew up and took out something plugged into it. Not the manufacturers fault, it was mine.

This discussion is interesting because people keep intimating the "Professional" installer did everything right and somehow everything blew up. This is not what happened. The installer made a mistake, and it seemed to be working but his error caused the equipment to behave in an unexpected manner under some conditions.

It needs to be addressed for the future but the error was done by the installer.
Click to expand...
Post in thread 'EG4 18K - What not to do in parallel' https://diysolarforum.com/threads/eg4-18k-what-not-to-do-in-parallel.84679/post-1105085

Right corrected this in post 90.
BTW I only found TWO crossover cables in my bin of various network supply of cat5/6. One of them was indeed a short GREEN cable about 3ft, and another was super long (didnt want to measure) custom made (diy end connectors) WHITE cable my dad must have made 20 years ago.
 
sunshine_eggo said:
I totally get what you're saying, but the installer did not violate the installation instructions per yesterday's manual.
Click to expand...
Excuse me? I'm sorry, I missed the line in the old manual that stated "You could use any random cable that has RJ-45 ends on it you might have laying around to connect the two inverters in parallel. The actual pinouts on the cable is not relevant." My bad, umm, what page was that on again? I have copies of 1.1, 1.2, 1.3, 2....

This problem, serious though it may be, was triggered by a careless installer using an incorrect cable, ie "MIS-WIRING" the inverters. Considering the implication of connecting two inverters in parallel pumping 50A each I made the assumption that cable was carrying a sync signal and verified the pinning before substituting it.

If provided a 4 foot chain to hang a heavy chandelier, and you decide you want a 6 foot hang instead, so you use your own chain around the same size, which breaks allowing the chandelier to crash into the glass table below it and break the table. There was nothing in the manual about the chain, weight limits, whatever, it just says hang it as shown. Are you trying to say you didn't violate the installation instructions? I would strongly disagree.
 
BuffaloTrace said:
Post in thread 'EG4 18K - What not to do in parallel' https://diysolarforum.com/threads/eg4-18k-what-not-to-do-in-parallel.84679/post-1105085

Right corrected this in post 90.
BTW I only found TWO crossover cables in my bin of various network supply of cat5/6. One of them was indeed a short GREEN cable about 3ft, and another was super long (didnt want to measure) custom made (diy end connectors) WHITE cable my dad must have made 20 years ago.
Click to expand...

Yeah, cross over cables are pretty old school. They stopped being used when switches and hubs and such started auto sensing what they were connected to I think.
 
Ok, there is still an elephant in this perverable room and we are all dying to know the answer to...

What or how is making 400v+ on the mains input side? The inverters saw themselves as being in parallel, but the comms cable wasn't correct.

I would love to hear a reasonable technical explaination. Can someone from EG4 or Lux do an RCA?
 
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I would say everybody involved in this scenario made a mistake. The installer did make a stupid easy to make mistake, but he was probably overworked, tired and angry about the short cable. At least everybody has learned something from it and nobody was killed.
 
ksmithaz1 said:
Excuse me? I'm sorry, I missed the line in the old manual that stated "You could use any random cable that has RJ-45 ends on it you might have laying around to connect the two inverters in parallel. The actual pinouts on the cable is not relevant." My bad, umm, what page was that on again? I have copies of 1.1, 1.2, 1.3, 2....
Click to expand...

There was NO mention of any specific cable at all, just "RJ45". Guy had a RJ45 cable. It had "Belkin" on it... quality cable, right? Long enough? Yep. Should work! Let's do it! It was installed according to the installation instructions.

You yourself indicated not to underestimate the ingenuity of a fool (or a similar version), are you back peddling on that? :p
 
cs1234 said:
I would say everybody involved in this scenario made a mistake. The installer did make a stupid easy to make mistake, but he was probably overworked, tired and angry about the short cable. At least everybody has learned something from it and nobody was killed.
Click to expand...

Now for the real twist... what if the homeowner supplied the cable? "Oh it's too short? I've got lots of those! Here! Try this one!"
 
ksmithaz1 said:
Excuse me? I'm sorry, I missed the line in the old manual that stated "You could use any random cable that has RJ-45 ends on it you might have laying around to connect the two inverters in parallel. The actual pinouts on the cable is not relevant." My bad, umm, what page was that on again? I have copies of 1.1, 1.2, 1.3, 2....

This problem, serious though it may be, was triggered by a careless installer using an incorrect cable, ie "MIS-WIRING" the inverters. Considering the implication of connecting two inverters in parallel pumping 50A each I made the assumption that cable was carrying a sync signal and verified the pinning before substituting it.

If provided a 4 foot chain to hang a heavy chandelier, and you decide you want a 6 foot hang instead, so you use your own chain around the same size, which breaks allowing the chandelier to crash into the glass table below it and break the table. There was nothing in the manual about the chain, weight limits, whatever, it just says hang it as shown. Are you trying to say you didn't violate the installation instructions? I would strongly disagree.
Click to expand...
I missed the part in UL 1741 where inverters can feed back to the grid when there is no input.
 
automatikdonn said:
I am not willing to take that chance. Those pairings effect how noise hits each twisted pair.
Click to expand...
You cannot electrically tell the difference between a T568A and T568B cable as long as both ends are exactly the same.
The pair in the middle is surrounded by a split pair for both types. The pair numbers do not change, only the coloration.
In a color-blind world, they would be identical cables.
 
sunshine_eggo said:
You forgot Victron. :)

However, it's a good point that the included cables are too short to facilitate installation clearances and raceway routing.
Click to expand...
Yes, I had this problem, they provide like a 7ft cable I needed like 8.5 to get down thru the conduit and back up. They really needed to improve the documentation, I've been bitching about parallel documentation since this time last year, but I would submit that this installation would have been horked had their been a red flag in the rj at each end with "Danger only use a straight thru cable" on it, because the installer obviously made an assumption about a cable they found and didn't look or check.

To that end, it is important that future versions and/or firmware updates detect a problem with the sync cable now that we know what it being wildly wrong does.

From a SWAG, I'm guessing it carries both sync and CAN signals some of which were working for whatever reason
 
automatikdonn said:
Ok, there is still an elephant in this perverable room and we are all dying to know the answer to...

What or how is making 400v+ on the mains input side? The inverters saw themselves as being in parallel.

I would love to hear a reasonable technical explaination. Can someone from EG4 or Lux do an RCA?
Click to expand...
At this point, especially with fried equipment( thank God no loss of life), your lawyer should already be talking to eg4 lawyers.
 
cs1234 said:
Yeah, cross over cables are pretty old school. They stopped being used when switches and hubs and such started auto sensing what they were connected to I think.
Click to expand...
RJ-45 satin cable for phones, straight thru and flipped. Hand crimped T-1's, that's 1/2,4/5 swapped. Old cisco cards . . . I've had occasion to use a crossover ethernet from time to time. Some of the Cox handoffs required it 3 or 4 years ago coming off the fiber gear.
 
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