OpticsRE says I have a magic free energy machine...

Discussion about the OutBack OpticsRE system monitor

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TCabin76
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Posts: 38
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My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Tue Jun 30, 2020 2:40 pm

Well it looks like the panels are on top of a pole, held by an apparatus the appears to be able to rotate. I need to get up there and check but it appears that Loosening a couple bolts should allow it to rotate L/R o top of the pole. Is there something else that would limit that rotation? I mean, other than it’s a PITA. :neutral:

provo
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Posts: 403
Joined: Thu Jul 27, 2006 4:34 pm
My RE system: Sixteen Evergreen EC-120
(4 strings, total 1920W)
Eight Rolls S-550 (2 strings, total ~800Ah @ 24V)
One FM80
One VFXR3524A
Hub 10
Mate3s
FNDC and Trimetric
Location: Sierra foothills

Re: OpticsRE says I have a magic free energy machine...

Post by provo » Tue Jun 30, 2020 2:51 pm

TCabin76 wrote:
Tue Jun 30, 2020 2:40 pm
Well it looks like the panels are on top of a pole, held by an apparatus that appears to be able to rotate. I need to get up there and check but it appears that Loosening a couple bolts should allow it to rotate L/R o top of the pole. Is there something else that would limit that rotation? I mean, other than it’s a PITA.
To me, that's great news \:D/ !! I use pole mounts for my panels and I love 'em. Not only can you experiment with different azimuth positions, east or west of due south, but you can (and I do!) adjust the elevation for the seasons, and gain maybe 10% more power over a year.

Hoping the pole is in the ground and easily accessible ....

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Tue Jun 30, 2020 3:01 pm

Yes, the pole is set in concrete. Should be accessible with a long enough ladder. As you suggest, I think there is more we can get from these panels. I don’t think the actual owner has had time or motivation to experiment. The system was working “okay”, but tripping the genny a fair amount. I think with some optimization they can save a bit of $ on propane.
Thanks again for your engagement in this thread. The collective wisdom is invaluable especially in a system like this with so many variables, many of them approaching the realm of black art. :grin:

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 7:37 am

To get back to the original issue: the OpticsRE data was showing more energy to the batteries than the PV was producing.

Per some of the suggestions here I made the following changes:

1) I disabled shunt C and removed it’s twisted pair (TP) from connection C on the FNDC - preciously shunt C had been connected at the Batt side but had nothing on the device side, yet the TP across it was connected to FNDC and shunt C was enabled in the MATE3 setup.

2) I moved the PV neg of the the array, to the battery side of the shunt B - previously it has been on the device side along with the PV & Batt neg from the FM80.

After making those changes I’ve watched the OpticsRE graphs for a couple days and I no longer see the original anomaly (see updated graph attached). However, delving into the manual for the FM80 I see that a wiring diagram that shows the PV neg from the the array connected to the device side of the shut - as it was in our system originally.

So, once again I’m struggling to understand which is correct. The documentation shows the original configuration, yet that gives erroneous data. Changing the configuration as described above improves the accuracy of the data but to a strict interpretation of the OB wiring diagram, that alternate configuration is wrong.

Uggg...

Underlying this whole experiment is the question of how the FNDC actually determines which shunt is connected to each of it’s terminals (A/B/C). I have searched for that info I. The FNDC manual but if it’s thee it eluded me. At this point, in order to get my head around variations in shunt wiring I really need to understand how the FNDC is interpreting the measurements at it’s own TP terminals. I would welcome any insight as part of this thread but I may start a separate subject regarding this question.

Thanks all!

RM
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EFD99A5B-EB85-4214-93B9-D4C2C23F15E8.jpeg

raysun
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My RE system: Flexpower One: FX3048T, (2) FM80, MATE3s, FlexNetDC
Outback 200NC batteries (8 @ 48v)
Outback IBR3 battery enclosure
Suniva 330 watt panels (12 - 6 strings of 2 in series)
Hyundai 355 watt panels (6 - 3 strings of 2 in series)
Honda EU7000is gas fuel generator

Re: OpticsRE says I have a magic free energy machine...

Post by raysun » Sat Jul 04, 2020 8:24 am

Removing the unused shunt by unplugging it from the FNDC will certainly remove any influence it has on the system - as long as the port is also disabled in the FNDC configuration as well. Disabling the unused port in the FNDC configuration alone would have the same effect.

Moving the PV neg. to the battery side of the shunt has induced a huge error on the OpticsRE summary screen. I would highly suggest reading up on the basic principals of current measurement via shunts - separated from the mental rabbit hole you are creating for yourself by messing with the system wiring.
Last edited by raysun on Sat Jul 04, 2020 11:51 am, edited 1 time in total.

provo
Forum Guru
Posts: 403
Joined: Thu Jul 27, 2006 4:34 pm
My RE system: Sixteen Evergreen EC-120
(4 strings, total 1920W)
Eight Rolls S-550 (2 strings, total ~800Ah @ 24V)
One FM80
One VFXR3524A
Hub 10
Mate3s
FNDC and Trimetric
Location: Sierra foothills

Re: OpticsRE says I have a magic free energy machine...

Post by provo » Sat Jul 04, 2020 10:05 am

raysun wrote:
Sat Jul 04, 2020 8:24 am

Moving the PV - to the battery side of the shunt has induced a huge error on the OpticsRE summary screen. I would highly suggest reading up on the basic principals of current measurement via shunts - separated from the mental rabbit hole you are creating for yourself by messing with the system wiring.
Oops, I really need to stop giving advice on this forum :oops: !! Sure enough, here's the ancient Outback schematic of something like my system:

Screen Shot 2020-07-04 at 10.00.09 AM.jpg

The PV- is indeed on the device side of the shunt, and that's how it has to be to keep that current from being counted by the shunt. I should have looked at the schematic before speaking up -- sorry!

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 11:43 am

Hmmm, well alrighty then.

Guess I’ll move it back.

I’m off to the power shed...

JRHill
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Re: OpticsRE says I have a magic free energy machine...

Post by JRHill » Sat Jul 04, 2020 12:25 pm

The FNDC has room for three shunts. Why are you ganging them on one side or the other? Just add another shunt and measure whats coming in from the panels/FM, another going out to the inverter or yet another going out/in elsewhere? It's a cool device. What am I missing?

What you can't easily get is in/out efficiency from the inverter for charging batteries/loads.
Last edited by JRHill on Sat Jul 04, 2020 12:34 pm, edited 1 time in total.

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 12:29 pm

raysun wrote:
Sat Jul 04, 2020 8:24 am
Removing the unused shunt by unplugging it from the FNDC will certainly remove any influence it has on the system - as long as the port is also disabled in the FNDC configuration as well. Disabling the unused port in the FNDC configuration alone would have the same effect.

Moving the PV neg. to the battery side of the shunt has induced a huge error on the OpticsRE summary screen. I would highly suggest reading up on the basic principals of current measurement via shunts - separated from the mental rabbit hole you are creating for yourself by messing with the system wiring.
Okay, PV neg from panel is now back on the bus bar along with PV neg & Batt neg from FM80. Appreciate the intervention.

Can you expound a bit on what you mean by “...a huge error on the OpticsRE summary screen.” ?

Thx!

RM

TCabin76
Forum Whiz
Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 1:24 pm

raysun wrote:
Sat Jul 04, 2020 8:24 am
Removing the unused shunt by unplugging it from the FNDC will certainly remove any influence it has on the system - as long as the port is also disabled in the FNDC configuration as well. Disabling the unused port in the FNDC configuration alone would have the same effect.

Moving the PV neg. to the battery side of the shunt has induced a huge error on the OpticsRE summary screen. I would highly suggest reading up on the basic principals of current measurement via shunts - separated from the mental rabbit hole you are creating for yourself by messing with the system wiring.
Also, while I certainly am no expert on how these shunts are utilized by the OB algorithm, I do know the basic function of a shunt. That is what led me to the original question about the termination of the PV neg from the array.

Based on the FM80 shunt wiring diagram, here’s my logic:

The Batt pos from the battery lands / terminates at the FM80. Then a Batt neg conduit exits the FM80, and connects to the device side of shunt B.

The PV pos from the array also lands at the FM80, and a PV neg conduit also exits the FM80, and connects to the device side of shunt B.

So far, so good - we have 2 power sources: Batt & PV going through the FM80 (ostensibly where they are managed), then both sources connect to the device side shunt B, through which they may be measured.

Okay, so Batt neg from FM80 now passes through shunt B and returns to the negative side of the battery. Makes sense to me that the battery current is now measurable through that shunt.

PV neg from FM80 also makes it to shunt B, but the only thing on the other side of shunt B is the negative battery return/busbar. In order for that PV circuit to be complete back to the neg side of the PV array, that current needs to find its way back to the PV neg to array, and in order for that current to be measured through shunt B it seems to me that return path needs to be on the battery side of shunt B.

But that’s not what happens...

The PV neg return to the PV array - PV neg from array - is also on the device side busbar of shunt B!

My basic electronics tells me that the PV neg return current from the the FM80 will go through the PV neg to array connection on the device side busbar of shunt B rather than through the shunt. Unless there is another path back to the PV neg side of the array, somewhere on the other side (battery side) of that shunt B, how is any of the PV current going to go through shunt B?

There it is folks. Please shoot any holes you can in that logic, and/or tell me how that PV neg current passes through the shunt when its return to the array is on the device side of the shunt.

Here’s another copy of my wiring schematic for reference.

Thanks!

RM
Attachments
Notability Notes.pdf
(386.63 KiB) Downloaded 4 times

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 1:30 pm

Aaaaand, now that the PVneg from the array is back on the device side of the shunt, I’m back to the OpticsRE giving erroneous data graphs. :sad:
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provo
Forum Guru
Posts: 403
Joined: Thu Jul 27, 2006 4:34 pm
My RE system: Sixteen Evergreen EC-120
(4 strings, total 1920W)
Eight Rolls S-550 (2 strings, total ~800Ah @ 24V)
One FM80
One VFXR3524A
Hub 10
Mate3s
FNDC and Trimetric
Location: Sierra foothills

Re: OpticsRE says I have a magic free energy machine...

Post by provo » Sat Jul 04, 2020 2:09 pm

TCabin76 wrote:
Sat Jul 04, 2020 1:24 pm

how is any of the PV current going to go through shunt B?
It's not, and you don't want it to -- only the batt minus of the FM80 should go to the shunt.

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 2:16 pm

JRHill wrote:
Sat Jul 04, 2020 12:25 pm
The FNDC has room for three shunts. Why are you ganging them on one side or the other? Just add another shunt and measure whats coming in from the panels/FM, another going out to the inverter or yet another going out/in elsewhere? It's a cool device. What am I missing?

What you can't easily get is in/out efficiency from the inverter for charging batteries/loads.
Hi JR, thanks for your input. My system actually does have 3 shunts installed. One of them was physically there but had nothing on the device side. If you look back through this thread you will see the history of that discussion.

I guess in the long run what I’m really trying to do with all this is to understand things well enough to make the kinds of changes you suggest. In my mind there should be a way to use shunts to monitor the currents in and around the system. I have done similar things to what you suggest in other off grid systems. But this is my first experience with the Outback. It’s more complex in that the inner workings of the algorithms are not transparent. The Optics RE monitor has some data graphs that, in my mind, imply certain conditions. Yet I have yet to be able to sus them all out. For instance: how can the Optice RE list current from solar and to battery as separate graph bars if both of those currents go through the same shunt? How can the graph for the current to battery show more current than the PV is supplying/

It’s puzzling, but I’m chipping away at my understand.

Thanks,

RM

raysun
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My RE system: Flexpower One: FX3048T, (2) FM80, MATE3s, FlexNetDC
Outback 200NC batteries (8 @ 48v)
Outback IBR3 battery enclosure
Suniva 330 watt panels (12 - 6 strings of 2 in series)
Hyundai 355 watt panels (6 - 3 strings of 2 in series)
Honda EU7000is gas fuel generator

Re: OpticsRE says I have a magic free energy machine...

Post by raysun » Sat Jul 04, 2020 2:21 pm

A friend's new off grid install had a battery monitor that was acting weird. After 10 exchanges of pictures, texts, and me explaining *again* the fundamentals of wiring the shunts, having him trace through the wiring, having his electrician trace through the wiring, having another friend trace through the wiring, I finally gave up and went over to look at it myself. It took about 30 seconds to point out they had the battery negative lead on the load side of the shunt, along will all the other DC components on the battery negative bus, and the Inverter battery negative lead on the battery side of the shunt.

What the heck? They're both thick black wires aren't they? Does it matter?

provo
Forum Guru
Posts: 403
Joined: Thu Jul 27, 2006 4:34 pm
My RE system: Sixteen Evergreen EC-120
(4 strings, total 1920W)
Eight Rolls S-550 (2 strings, total ~800Ah @ 24V)
One FM80
One VFXR3524A
Hub 10
Mate3s
FNDC and Trimetric
Location: Sierra foothills

Re: OpticsRE says I have a magic free energy machine...

Post by provo » Sat Jul 04, 2020 2:29 pm

TCabin76 wrote:
Sat Jul 04, 2020 2:16 pm

how can the Optice RE list current from solar and to battery as separate graph bars if both of those currents go through the same shunt?

The From Solar data doesn't go through any of the FNDC shunts -- it goes directly from the FM80 to the Mate, presumably through the Cat5 cables.

raysun
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My RE system: Flexpower One: FX3048T, (2) FM80, MATE3s, FlexNetDC
Outback 200NC batteries (8 @ 48v)
Outback IBR3 battery enclosure
Suniva 330 watt panels (12 - 6 strings of 2 in series)
Hyundai 355 watt panels (6 - 3 strings of 2 in series)
Honda EU7000is gas fuel generator

Re: OpticsRE says I have a magic free energy machine...

Post by raysun » Sat Jul 04, 2020 2:50 pm

"For instance: how can the Optice RE list current from solar and to battery as separate graph bars if both of those currents go through the same shunt?"

OK maybe 3rd time's a charm.

SOLAR is taken from the OUTPUT of the FM80 charge controller(s) as reported by their internal ammeters. This value IS NOT measured across ANY shunt in the system.

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 3:10 pm

provo wrote:
Sat Jul 04, 2020 2:29 pm
TCabin76 wrote:
Sat Jul 04, 2020 2:16 pm

how can the Optice RE list current from solar and to battery as separate graph bars if both of those currents go through the same shunt?

The From Solar data doesn't go through any of the FNDC shunts -- it goes directly from the FM80 to the Mate, presumably through the Cat5 cables.
Very interesting! That would explain why the PV array neg is on the device side busbar along with the PV neg from the FM80 - it is just a convenient p/lace to tie them together. The fact that it is also where the Batt neg from FM80 lands as it’s device side connection to the shunt, is purely coincidence, in reality that shunt is only for the battery current.

The PV neg from FM80 could connect to the PV array neg, on a separate busbar somewhere unrelated to the one on the device side of the shunt. That would take more hardware of course, but would be a little more obvious to trace.

This realization also implies that here must be a shunt or some similar current sensing mechanism inside the FM80. That begs the question of why the battery current needs it’s own external shunt when the PV current uses the FM80’s internal sensing. But I digress...

Thanks for that insight

RM

TCabin76
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Posts: 38
Joined: Sun Jun 21, 2020 12:36 pm
My RE system: Outback Off-Grid system: 8 - Kilovault 12V/180Ah AGM batteries (2 parallel banks of 4 series batteries for 48V / 360Ah); Kilovault 48 V battery balances - 1 per parallel bank; 3200W PV array (12x270W panels); 2- VFX3648’s (split phase master & OB slave L2) ; 1-FM 80; 1-FNDC; backup genny. MATE3.

Re: OpticsRE says I have a magic free energy machine...

Post by TCabin76 » Sat Jul 04, 2020 3:15 pm

raysun wrote:
Sat Jul 04, 2020 2:50 pm
"For instance: how can the Optice RE list current from solar and to battery as separate graph bars if both of those currents go through the same shunt?"

OK maybe 3rd time's a charm.

SOLAR is taken from the OUTPUT of the FM80 charge controller(s) as reported by their internal ammeters. This value IS NOT measured across ANY shunt in the system.
Raysun, I don’t know where / when the other 2 times were that you have expressed this but thanks for persevering. Please understand there is a lot if I information to digest here and nomenclature that is familiar to you folks is all still getting sorted with us noob’s. Sometimes a question needs to be asked more than once and answered in different ways to get the point across.

I appreciate your patience.
:grin:
Thanks!

RM

Mike Curran
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My RE system: Outback - Garage roof:
- 8 (2x4) Evergreen 180's into one FM80 (2007/2020 repl'd MX60)
- 6 (2×3) ALEO S79-300's into one FM80 (2017)
- 2 grid-tied GVFX3524's classic stacked for 120/240VAC (2007)
- 12 Surrette/Rolls 2V x 1766Ah (2007)
- Hub10.3, Mate3s, FNDC, RTS, OpticsRE. Tigo Energy ES maximizers on each PV module.

Westinghouse Solar - Barn roof: (2012)
- 30 (2x15) 235W panels with Enphase M215 microinverters, grid-tied, no longer AC- coupled

Outback Skybox - Barn roof: (2019)
- 14 (2x7) Talesun 275W (DC array input to SB charger)
- 3 SimpliPhi 3.8 batteries, 48V, 225Ah total
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All self-designed and self-installed
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Re: OpticsRE says I have a magic free energy machine...

Post by Mike Curran » Sat Jul 04, 2020 7:05 pm

Actually, we all have magic free energy machines. The machine may not be free, but the energy from the sun surely is. :grin:
http://www.tigoenergy.com/site.php?95b2dca2-ca6c
https://enlighten.enphaseenergy.com/public/systems/Hctc107221

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