Replaced inverter now shows both lights green!

softdown

For some reason I expected that. What to do now?

Guess I'll wait for an idea. Or maybe tear into it and look for damaged parts. Heat can keep a damaged part from working etc.

BB.

You might want to keep this all in one thread. Hard to follow when q&a is spread in other discussions.

-Bill

softdown

All three boards look stone cold perfect. Brand new in fact.  Tiny bit of dust on part of the copper coils on the transformer. Other than that - all looked brand new.

Was missing an o-ring on the negative battery terminal. Perfect other than that.

I'm currently feeling like maybe it was just a tiny glitch caused by quarks or whatever they call those tiny bits floating around that cause errors in computer memory etc. Hence the EC memory sticks - error correcting.

So - run two systems? Have everything I need to do that. Would take 1-2 hours. Talk about almost bullet proof immediate backup!

softdown

BB. said:

You might want to keep this all in one thread. Hard to follow when q&a is spread in other discussions.

-Bill

Perhaps. Was thinking that few would read a large number of posts. More likely to respond to a solitary post. Thats what I was thinking. If you fell like consolidating - wonderful.

BB.

I cannot consolidate posts in "Vanilla BB" software--Only split threads... 

-Bill

mike95490

Are green lights good ? or is there still an issue with the inverter ?

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mike95490 said:

Are green lights good ? or is there still an issue with the inverter ?

Yes they are. Re-assembled and hooked up to 48V battery bank. Guess I will get an idea of the inverter power draw, sans load, tonight. The lights have been green for some time now.

But that is probably meaningless without a significant and prolonged load.

If I had to point out a suspect, it would be the six huge capacitors. Though they all look brand new. A new FET board is close to $600. More than I feel inclined to spend given the unknowns.

Board work is pretty straight forward. One 10mm bolt was a bit of a challenge.

softdown

Right now it seems like I should hook up the inverter to my biggest power draw - a massive freezer bought in 2020. I don't recall Energy Star ratings - I think it was either commercial or somehow flew under normal radar. Costco's business stores are known to try products that the main stores do not carry. I plan to give that a show when I will be here 24/7 while trying it. Plus put a temp alarm on that freezer. Or a power outage alarm for that matter.

If it powers the massive freezer for a week with no issues - I figure I can probably keep it for back up.

Then again - having an inverter built in 2012 and used lightly for 6 1/2 years doesn't seem like the greatest back up plan.

Having two separate 48 volt systems would be easy enough. Then:

1) I am wearing out two systems instead of one.

2) The power draw of one 3648 is significant.

A nice problem in a way - I may have two good inverters. Or do I? Why did the old inverter quit last week? Everything looks new inside.

Does this happen with good inverters on rare occasions? Just needing a reboot or something? I tried flipping the switches several times. But I am very far from an electrical guy, getting by most of the time.

softdown

Three new boards is about $1200, the labor is easy. But the replacement inverter may last 10-12 years itself. So my back up inverter could be 21 years old at that time.

FET board is $600. Too much for a "This might be the issue replacement."

Would replacing the control board update the old inverter to better accommodate lithium batteries?

I won't sell an inverter that might die quickly. No option there. It really needs someone that can figure out what happened.

softdown

So I stripped the male end of a 10/2 outdoor cable with four females. The plan is to power the bedroom when I know I'll be here for quite awhile. Losing internet is a quick way to know that power is lost.

Too bad about using two 3648s simultaneously. Hope they don't "fight" each other. Just can't think of another good solution to this conundrum. If the old 3648 works good for two weeks then I guess it should be alright after all.

softdown

What happens when two 3648s are hooked up to the same battery bank? They have been that way for a couple days now but no power draw on one. Just idling along - power draw from idling isn't bad.

mike95490

inverters can share a power source ( batteries ) just fine.   But combining their outputs requires them to be synchronized.

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mike95490 said:

inverters can share a power source ( batteries ) just fine.   But combining their outputs requires them to be synchronized.

Good to hear. Plan:

New inverter: Powers breaker box.

Old inverter: Just powers bedroom. It is a a test for longevity. If it passes I will hook it up to the well and see how it does, I suspect there is a 50/50 chance it is fine. Got a bug and failed one fine day though.

BB.

Just watch your battery state of charge... You did add some power draw with the second inverter:

https://www.outbackpower.com/products/inverter-chargers/fxr-vfxr-series

Full: ≈34W Search: ≈9W Off: ≈3W

• 34 Watts * 24 Hours per day = 816 WH per day

About 1/2 of the power for a full size fridge.

-Bill

softdown

Outback board poster Raysun said this: Hopefully the replacement unit is a VFXR3648A (the older VFX3648 is discontinued.) The newer model is ideal for use with lithium batteries.

The old unit can be repaired and sold, most likely. There are three boards that are replaceable: AC Input, Control, and Power FET. Most likely one of the two latter boards is the culprit.

An acquaintance in the Caribbean mentioned that if the VFX3648 Control and Power FET boards are replaced with the VFXR versions, the unit would be upgraded to the current model specifications. I have no way of confirming that, but its an interesting notion to revamp the old war horse and keep it for backup, or for stacking.

Name seems familiar from 2014 - I think. But nothing concrete was said. Still $900, good chance that is more than I seek to spend.

For future reference- likely the FET and control boards. So far. That $600 FET board makes me want a Rittenhouse. Chaser followed by three shots.

softdown

I was replacing an east wing security light when the inverter gave out. The electrical panel for the east wing had been shut off. But that failed to disconnect  power to that security light. I sure don't recall any lines that bypassed the main electrical panel.

Is it even possible that replacing the security light tripped the inverter? Causing it to shut down?

BB.

If it was the old 100 Watt filament type bulb... Yes. I had such a security light burn out and trip the main breaker for my home (years ago).

-Bill

softdown

It was motion activated LED security light with video memory card. Since I thought the power was off it is entirely possible that the wires were allowed to touch while replacing it. Power should have been routed through a circuit breaker though. However it could explain the inverter shutting itself off  perhaps - if a circuit breaker somehow got bypassed?

BB.

Circuit breakers are relatively "slow" when compared to inverter electronics. It is certainly possible to electronically "trip" the inverter without tripping the physical breaker.

However, once the inverter is "reset" (cycling DC power to inverter or whatever is required)--It should be running again. If not...

-Bill

softdown

But I would think that flipping the main bottom left switches, more than once, would have reset everything.

BB.

I have no idea--If that was the DC breaker to the inverter (for a couple of minutes to let the DC caps discharge)--Then yes, I would guess it would reset the inverter... Don't know what bottom left switches are. Switching AC output breakers, may not do anything.

But I would have to read the manual (if it even says) to be sure.

-Bill

softdown

The bottom left switches are the only ones I ever touched until I had to bypass the inverter to feed the breaker box by genset,

Right now my thinking is this. If the inverter feeds the bedroom needs for two weeks then is able to service the well for an ~150 gallon draw - I will likely count on the inverter if I ever get my next home built in Forbes Park. About 35 miles away with cooler summers and much much better scenery. Want to do an earth home this time. Already have the support steel beams and a picture in my head.

This house can require $100/year in propane for heating. My idea will take about $10/year in propane - perhaps a little optimistic. Cool in the summer as well.