Generator backup

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clarkef
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Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Mon Feb 10, 2020 8:03 pm

Swampdog wrote:
Mon Feb 10, 2020 4:52 pm
Amp-hours... I have 12 x 220GH batteries. Don't know how to calculate and could not find a spec.

I would want to optimize grid sell, as since grid-tied, the back-up is only needed during outages. Generally, the array output is enough for our daily loads.

Not sure how to answer. I do not have a charge controller, but we can receive power during array production and sell at the same time, excess from array also charges batteries.
Do you have a remote operated circuit breaker which disconnects your string inverter when the generator is running? Based on the age of the system, I would expect one. If you look in your GSLC there should be a complicated looking two pole breaker with an extra pole?

12x 220Ah batteries for a 48V system means four 12v batteries in series for 48v, and three sets of four in parallel. So as Raysun said 660AH of total capacity at a C20 rate (330AH usable). Each battery according to specs can be max charged at over 100A, so you don’t really have any limits on rate of charge with three sets in parallel. So no reason to limit the AC charger. If you aren’t load shifting and these are battery backup, then the must sit at float all the time?

When you say the array output is enough for daily loads, are you including net metering in that or are you using the batteries daily for a net zero loadshifting?

You goal when under generator would be to recharge as fast as possible. To me, that means running your AC charger at whatever rate your inputs support. 20 AAC for generator in, and 18 (or 20) for AC charger.

Net-net you want the solar or the generator to recharge the batteries as fast as possible when not connected to the grid. The way AC coupling should work is excess to demand AC produce by your SolarEdge feeds loads (including the Radian charger). Once batteries go to flood or stop charging, that AC demand drops and it feeds other house loads and then grid. All you are doing by reducing the AC charger rate is increasing the time that it takes to top off the batteries. The excess to seep should be about the same.

When you go to generator to charge batteries, the ROCB you probably have should open, disconnecting the AC from your SolarEdge and knocking it offline. Hooking a grid-tie inverter together with a generator is a no-no and will result in you likely needing a new generator - thus the ROCB.

If you lose the grid, the max your SolarEdge could put in currently is 7.5AAC or 1800 watts or 37ADC. Presumably if you are using the Radian in backup mode you might never be able to recover your batteries from AC coupling in a grid-down faster than you use the power with charging choked down to 7.5AAC.

Any sense of what your average AC load is when running in backup mode? You could drop the AC charger rate by that amount just to keep the Radian from having to juggle / throttle charging up and down as loads vary.

Swampdog
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Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Tue Feb 11, 2020 11:08 am

I reiterate... I am no electrician. I speak only layperson, but will do my best to answer your questions:

Remote breaker: sounds like you may be referring to the ROBC relay, which was removed wit the the upgrade to MATE3s and firmware, adapted to handle AC Coupling. Attached is an image of my GSLC panel and the a new relay installed at the same time. Don't know what it is and my installer merely instructed me not to touch the dial settings.

Amp-hours: Yes, 660AH for battery bank. The system does seem to sit in Float, except during my varying outage response fiascos. I can say, after 16 outages, and many "solutions" and equipment changes, I have yet to experience a backup process that was not problematic. When I recently changed the High Battery Cut-In and Cut-Out settings, I think that allowed Absorb to occur, which I had not seen for months. My last adjustment stopped the intermittent Buying, which I think might have been the 4-hour setting for the Absorb cycle. I changed HB CUt-in and out from the default (60v & 64v to 58v & 60v). All is running smoothly at the moment (Selling), but then, we are not in an outage.

Daily loads: Not understanding all this, but usually, we are at OkW load, with "from battery: under .01kWh and Selling (currently 3.4kW). So wondering, even overnight with no array production, our "from battery" stays under .01kw with no gird usage indicated ("to battery"/Buying), unless there is an outage. During an outage, battery usage rises and batteries seem to deplete much faster, even with almost no consumption going on overnight.

No more ROCB, but to connect the generator (manually), I follow Outback procedures which is to disconnect the SolarEdge and open the L1/L2 breakers before connecting.

Grid down: Charging at 7.5AAC makes sense... so what would you recommend setting to? I originally had only a manual-connect generator, but kept that option for just the reason you mentioned. I understood that in good daylight, it would not bee needed to supplement the array production except during a prolonged outage, where we might not recharge fully each day.

AC load: Critical loads high users are well pump (intermittent), freezer, 2 frigs, water heater & heater/boiler (intermittent or not at all). Overnight... no well pump and only one outside light, frigs, boiler, hot water maintenance temp). Maybe 3700 watts max between these items. OpticsRE reports typically <.01kWh "from battery" night and day.

I truly appreciate your efforts on my behalf, although picking up knowledge along the way, I am drowning in trying to comprehend the interactions of settings and to get this system to work smoothly during an outage... while working full-time. After all... backup during outages was the main goal!

S
GSLC Breakers 20191025_125256.jpg
GS Load Center SLC175-PV-120V240.JPG
Relay 20191023_155442.jpg
/D

clarkef
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Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Tue Feb 11, 2020 4:55 pm

Swampdog wrote:
Tue Feb 11, 2020 11:08 am

Remote breaker: sounds like you may be referring to the ROBC relay, which was removed wit the the upgrade to MATE3s and firmware, adapted to handle AC Coupling. Attached is an image of my GSLC panel and the a new relay installed at the same time. Don't know what it is and my installer merely instructed me not to touch the dial settings.

Amp-hours: Yes, 660AH for battery bank. The system does seem to sit in Float, except during my varying outage response fiascos. I can say, after 16 outages, and many "solutions" and equipment changes, I have yet to experience a backup process that was not problematic. When I recently changed the High Battery Cut-In and Cut-Out settings, I think that allowed Absorb to occur, which I had not seen for months. My last adjustment stopped the intermittent Buying, which I think might have been the 4-hour setting for the Absorb cycle. I changed HB CUt-in and out from the default (60v & 64v to 58v & 60v). All is running smoothly at the moment (Selling), but then, we are not in an outage.

Daily loads: Not understanding all this, but usually, we are at OkW load, with "from battery: under .01kWh

No more ROCB, but to connect the generator (manually), I follow Outback procedures which is to disconnect the SolarEdge and open the L1/L2 breakers before connecting.

Grid down: Charging at 7.5AAC makes sense... so what would you recommend setting to?

AC load: Critical loads high users are well pump (intermittent), freezer, 2 frigs, water heater & heater/boiler (intermittent or not at all). Overnight... no well pump and only one outside light, frigs, boiler, hot water maintenance temp). Maybe 3700 watts max between these items. OpticsRE reports typically <.01kWh "from battery" night and day.
Okay, I’ll do my best, but Raysun might have more relevant experience on your battery settings. I’m not a lead acid battery guy.... given the age of the system, and the lack of confidence in your previous battery settings, it might be a really good idea to load test them to see what capacity remains after 3 years. Are you doing equalize cycles on the GH batteries? Outback literature calls is a “freshening charge”.

You are AC coupled. While you have the older ROCB from the old AC coupling control, it’s been replaced with the updated Radian firmware and the Radian is using freq/watt to control charging from your solar edge.

You are not using any battery capacity to load-shift - thus your batteries stay in float most of the time. That explains your “from battery” being effectively zero when grid-tied.

Yes if your absorb time was four hours, it’s possible that the SolarEdge might not have completed the 4 hr absorb cycle while it was still putting enough juice out (especially When combined with a very low AC charge rate) which would require juice from the grid to complete after SolarEdge production ceased.

I would think that an AC charge rate of 100% of your SolarEdge max AAC output would be appropriate. You aren’t going to lose anything to grid-sell since your batteries mostly sit in float - and this way in an outage any excess production not needed by the AC loads while the SolarEdge is producing would be available to charge batteries. Same for the next morning when your batteries are depleted - all available excess AC would be consumed by the charger until the batteries caught up and the Radian gets into Freq/watt mode to curtail SolarEdge production as appropriate to your AC loads.

That third picture might very well be a generator interlock relay (weird it’s programmable) as per the new AC coupling wiring diagrams. In what power mode does the relay ever change state?

Clarke

Swampdog
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Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Tue Feb 11, 2020 5:15 pm

Take me awhile to absorb all this.

I understood the ROCB was removed with the firmware update.

I have no idea what the "generator interlock" is or what it does, so can't tell you when/if it ever changes. I also don't know what the setting dials are for, or even where to find out.

S/D

clarkef
Forum Virtuoso
Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Tue Feb 11, 2020 7:12 pm

Swampdog wrote:
Tue Feb 11, 2020 5:15 pm
I understood the ROCB was removed with the firmware update.

I have no idea what the "generator interlock" is or what it does, so can't tell you when/if it ever changes. I also don't know what the setting dials are for, or even where to find out.
The breaker in the GSLC labeled L1/L2 sure looks like the old style ROCB. It’s in the right place for it. I can’t read the writing on it as the picture isn’t good enough. I assume that is the breaker you turn off when are are preparing to run the generator?

Does the light on the new box turn red when you are on generator! Does it turn red at any time? According to the new wiring app note on AC coupling, See Page 9 of the app note here.

http://www.outbackpower.com/downloads/d ... p_note.pdf

Basically the Outback recommended wiring config would detect generator power at the GSLC and open the circuit to the SolarEdge to prevent the two from ever meeting. That’s what an interlock does. Open one thing and it turns off another. IF that is what that relay is, your manual step of opening the ROCB is added insurance. AND I would expect the light to turn red when generator power is applied.

Cheers,

Clarke

Swampdog
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Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Wed Feb 12, 2020 5:55 pm

I have attached images of my GSLC and the Generator Relay with the labels added, hopefully you can see them. I added these labels.

Yes, it looks like the relay is for generator protection for automated starting. My generator is a manual connect/start connection, and I have always done the manual GTO disconnect. It sounds like the the relay was not needed for a manual connect/GTI disconnect, but it was installed anyway... maybe required, maybe not trusting I would do the GTI disconnect. Are you saying that the manual disconnect should not be necessary with this relay installed? I have never tried not doing the manual GTI disconnect, as I learned from the Outback app note.

Are you able to tell me what the settings are on the relay and what they should be set at? Do these settings look right? (not very precise).

S/D
GSLC Breakers 20191025_125256 labeled.jpg
Relay 20191023_155442 labeled.jpg

clarkef
Forum Virtuoso
Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Wed Feb 12, 2020 7:53 pm

Swampdog wrote:
Wed Feb 12, 2020 5:55 pm
My generator is a manual connect/start connection, and I have always done the manual GTO disconnect. It sounds like the the relay was not needed for a manual connect/GTI disconnect, but it was installed anyway... maybe required, maybe not trusting I would do the GTI disconnect. Are you saying that the manual disconnect should not be necessary with this relay installed? I have never tried not doing the manual GTI disconnect, as I learned from the Outback app note.

Are you able to tell me what the settings are on the relay and what they should be set at? Do these settings look right? (not very precise).
When it’s night time and there is no chance of PV production from your grid tie inverter do the following tests.

Open the L1/L2 breaker in the GSLC - what light if any is lit on the interlock relay in the cut box?
With the L1/L2 breaker still open, start your generator and apply power to the inverter. What light, if any, is lit? If not change wait 5 minutes and check again.
Turn your generator off, did the interlock relay change state? If not, Wait 10 minutes and check again. State?
Start the generator.
Open the PV DC disconnect into your SolarEdge.
Close the L1/L2 breaker in the GSLC. Did the SolarEdge energize?

Record and report back.

Testing complete - put things back to normal.

Stop generator. Close PV DC disconnect. Close L1/L2 breaker in GSLC. Check that power is applied to the SolarEdge.

Without knowing the exact model number of the relay, I can only provide generic answers. UMin and Umax determine the minimum and maximum voltages Sensed for the relay to change state. Time is probably the length of time needed with voltages between UMin and Umax before the relay agrees that, yes parameters have been met, and the relay changes state.

Yes it’s likely they included it to keep you from frying your generator by the SolarEdge pushing solar production into it while it’s running. Most residential generators DO NOT handle an external AC source back feeding them. It’s a great way to let the smoke out of your equipment.

Clarke
.

Swampdog
Forum Guru
Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Thu Feb 13, 2020 4:18 pm

clarkf;

In response to your previous post:

There is an EQ cycle: EQ VOltage = 58.4, EQ TIme = 1 hours (both are default)

clarkf: "I would think that an AC charge rate of 100% of your SolarEdge max AAC output would be appropriate."

Is this the Radian "Charger AC Limit" setting? Default limit cited is 30AAC, but my setting is at 7.5AAC (I didn't enter or change this setting). I don;t know how tyo apply the SolarEdge specs to these settings.

The SolarEdge 6000A cites the following:
Rated AC POwer Output: 6000 VA
Max AC Power Output: 6000 VA
Maximum Continuous Output Current: 27A

clarkf: "Any sense of what your average AC load is when running in backup mode? You could drop the AC charger rate by that amount just to keep the Radian from having to juggle / throttle charging up and down as loads vary."

Would this be an operating appliance amps estimate? My big power users (well pump, freezer, etc.) are intermittent, so how to address... max or average?

clarkf: "You goal when under generator would be to recharge as fast as possible. To me, that means running your AC charger at whatever rate your inputs support. 20 AAC for generator in, and 18 (or 20) for AC charger."

Currently set as follows:
Gen Input AC Limit: 12.5AAC (Default = 50AAC)
General>Charger AC Limit: 7.5 AAC (Default = 30AAC

So, you are suggesting Changing to:
Gen Input AC Limit: 20 AAC
General>Charger AC Limit: 18 AAC (or 20)

Thanks!!!

S/D

fcwlp
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My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: Generator backup

Post by fcwlp » Thu Feb 13, 2020 5:40 pm

download/file.php?id=3167&mode=view

In the above photo you posted a couple of days ago, it looks like the bottom white plastic mount for the neutral bar is rotated to the left. This bonds the neutral to the ground in the GSLC. As you are grid-tied you want to remove this bond as explained in the GSLC installation manual. There should be only one bond and for a grid-tied system this is at the service entrance. I had an issue once with offgrid VFXR system where the generator N-G bond caused issues as there was also the desired N-G bond in the inverter wiring box.

clarkef
Forum Virtuoso
Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Fri Feb 14, 2020 4:50 am

Swampdog wrote:
Thu Feb 13, 2020 4:18 pm
There is an EQ cycle: EQ VOltage = 58.4, EQ TIme = 1 hours (both are default)

clarkf: "I would think that an AC charge rate of 100% of your SolarEdge max AAC output would be appropriate”

Is this the Radian "Charger AC Limit" setting? Default limit cited is 30AAC, but my setting is at 7.5AAC (I didn't enter or change this setting). I don;t know how tyo apply the SolarEdge specs to these settings.

The SolarEdge 6000A cites the following:
Rated AC POwer Output: 6000 VA
Max AC Power Output: 6000 VA
Maximum Continuous Output Current: 27A

clarkf: "Any sense of what your average AC load is when running in backup mode? You could drop the AC charger rate by that amount just to keep the Radian from having to juggle / throttle charging up and down as loads vary."

Would this be an operating appliance amps estimate? My big power users (well pump, freezer, etc.) are intermittent, so how to address... max or average?

clarkf: "You goal when under generator would be to recharge as fast as possible. To me, that means running your AC charger at whatever rate your inputs support. 20 AAC for generator in, and 18 (or 20) for AC charger."

Currently set as follows:
Gen Input AC Limit: 12.5AAC (Default = 50AAC)
General>Charger AC Limit: 7.5 AAC (Default = 30AAC

So, you are suggesting Changing to:
Gen Input AC Limit: 20 AAC
General>Charger AC Limit: 18 AAC (or 20)

Thanks!!!

S/D
I can’t speak to your lead acid battery equalize times well, but 1 hour is not enough for a refresh based on your battery’s manual that I looked at online. Might be a good question for outback support or someone like Raysun who lives with lead acid batteries daily. Another thread might be appropriate. At 3 years old they are coming up on their 1/2 usable half-life. Running a load test when you have grid as a backup might be a good idea to know how much remaining capacity they have. It might be appropriate to run a refresh as per the manual. I would check all battery charge settings agains the GH 220 recommended values. What is the saying about batteries? That you kill your first set of batteries trying to figure out how to take care of them.....

Yes, I’m suggesting changing Gen Inout AC limit to 20AAC (or whatever wattage your generator supports for continuous operation. I think you or Raysun said that model supports 20A continuous?

With first of those two changes, Gen Input Limit, the inverter will be able to pull max power under generator - making generator power use much more effective. Right now, the Radian will throttle / limit the draw on the generator to your critical loads at about 60% (12.5AAC) of its max sustained capability. No wonder you haven’t been happy when you have had to fire it up.

The second recommended change to the AC charger limit is more complicated. Maybe. As there is no time of use schedule for battery charging, batteries will charge whenever an AC source is present (grid and/or SolarEdge OR generator) AND the batteries fall into re-float or meet parameters for charging. (I should add I don’t know if you can ‘schedule’ battery charging - I’ll need to research it, but nothing comes to mind.)

If you are grid tie, I don’t think limiting Charger AC limit down matters - it will pull from the grid night or day and recharge the batteries as needed once charging is triggered at a max of whatever limit you set. If the SolarEdge is online it will help offset the charger grid use. The one thing your AC charger limit does is minimize the max draw from ANY AC source to charge - extending battery recharge times in any circumstance where you might need to bring batts state of charge percentage up. As your SolarEdge can put out a max of 27AAC, you might want to set your AC Charger limit to that value. Or put it at 30AAC - so as to maximize charging when the grid comes back after an outage. Really, it is your call. The Radian SHOULD manage demand between loads and charger fairly well. If you try it and you get too much sag as the Radian tries to balance a new load demand, lower the limits to leave more generator ‘headroom’. That will have the effect of slowing recharge, but might be needed to help your generator carry start-up loads better. Remember the Radian will ‘throttle’ the AC input to your generator l8mit, removing the burst headroom of the generator unless you program in a larger Gen limit and throttle the charger so it won’t try and pull max current for a sustained period in excess of your generators limit. I say experiment and find out.

For me, I’m off-grid, so I want to get max charging rate I can, within the limits of my generator. I can put out about 25AAC sustained off my 5K military genset (I only get more than 100% rated output when servicing non-inductive loads - the military rates their generator output at .8 power-factor unlike civilian models). I have my AC Charger Limit set to 30AAC and my Gen AAC in limit set to 25. I let the Radian balance between loads and charging. Works fine for me except for unbalanced AC inductive loads (120V house pressure pump) which really loads the generator up until the start-up surge subsides. Might kick off a gas generator - I say try some bigger settings and see.

My goal under generator is to get as much juice into the batteries as quickly as possible - so I can turn off the generator. Your goal when the utility is gone, should be similar - unless you like the sounds of your generator?.

So set your Charger AC Limit to whatever - but much higher than 7.5AAC. anything less than 27AAC will limit recharge from the SolarEdge when utility power is out.

The tests from my previous post are about figuring our your grid-tie interlocks and breaker sequence and what’s where in the scheme of things.

Hope that helps.

Clarke

clarkef
Forum Virtuoso
Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Fri Feb 14, 2020 5:09 am

fcwlp wrote:
Thu Feb 13, 2020 5:40 pm
download/file.php?id=3167&mode=view

In the above photo you posted a couple of days ago, it looks like the bottom white plastic mount for the neutral bar is rotated to the left. This bonds the neutral to the ground in the GSLC. As you are grid-tied you want to remove this bond as explained in the GSLC installation manual. There should be only one bond and for a grid-tied system this is at the service entrance. I had an issue once with offgrid VFXR system where the generator N-G bond caused issues as there was also the desired N-G bond in the inverter wiring box.
Good catch! The same is true for your generator as it is for the inverter - if there is a neutral/ground bond on the generator, it too should be removed.

Swampdog
Forum Guru
Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Fri Feb 14, 2020 2:00 pm

Update:

OK.

Settings changes:
GS80481>AC Input>General>Charger AC Limit: Changed from 7.5A to 30AAC. (Default = 30AAC)
GS80481>AC Input>Gen>Gen Input AC Limit:: Changed from 12.5 AAC to 20AAC. (Default = 50AAC)
From generator specs:
Rated Maximum Continuous AC Load Current:
At 120 Volts . . . . .45.8 Amps
At 240 Volts . . . . .22.9 Amps

Bonding issues:
With the bonding issue, I think you are referring to GSLC Install manual pages 33-34, clearly stating:
"Make sure that no more than one bond is present in the AC system at any time."
"The GS Load Center (GSLC) is equipped with a neutral-ground bond. If bonding is required to be in another location, the bond in the GSLC may need to be removed."
"If other bonds are present, or if a GFDI is installed later, the GSLC bond needs to be removed."

GSLC: Attached is a current image of my GSLC wiring, after the FNDC was installed. I believe I see the bars & mounts you are referring to and the mechanic seem simple. However, I am hesitant to stick my hands in there and mess around (remember... no electrician!). What should I shut off to avoid electrocution or system destruction?
I may even contact my uncooperative installer and give him a chance to correct this, which was clearly an installation error... obvious in the manual.

Can you tell me... what are the potential issues with this/these unnecessary neutral bond(s)?
GSLC Bonding images 2020.pdf
(270.85 KiB) Downloaded 216 times
Bonding - Page from GSLC - gs_loadcenter_install.jpg

Thanks continuously for your attention to my issues and slow learning curve! NOTE: I get lost in some of the jargon, like...
"If you try it and you get too much sag as the Radian tries to balance a new load demand, lower the limits to leave more generator ‘headroom’." (no idea what "sag" and "headroom" are)

S/D

fcwlp
Forum Guru
Posts: 345
Joined: Wed Jan 22, 2020 9:40 am
My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: Generator backup

Post by fcwlp » Fri Feb 14, 2020 2:59 pm

Swampdog wrote:
Fri Feb 14, 2020 2:00 pm
Bonding issues:
With the bonding issue, I think you are referring to GSLC Install manual pages 33-34, clearly stating:
"Make sure that no more than one bond is present in the AC system at any time."
"The GS Load Center (GSLC) is equipped with a neutral-ground bond. If bonding is required to be in another location, the bond in the GSLC may need to be removed."
"If other bonds are present, or if a GFDI is installed later, the GSLC bond needs to be removed."

GSLC: Attached is a current image of my GSLC wiring, after the FNDC was installed. I believe I see the bars & mounts you are referring to and the mechanic seem simple. However, I am hesitant to stick my hands in there and mess around (remember... no electrician!). What should I shut off to avoid electrocution or system destruction?
I may even contact my uncooperative installer and give him a chance to correct this, which was clearly an installation error... obvious in the manual.

Can you tell me... what are the potential issues with this/these unnecessary neutral bond(s)?
You are correct on the GSLC manual location. It is hard to see the white buss bar support with the addition of your FNDC wires but it does appear to be in the condition as shipped from the factory. In addition to correcting this, confirm that there has been no wire added connecting the neutral buss bar and the ground buss bar that you also circled.

When the factory wires the FNDC in the GSLC they manage to get all of the twisted wire pairs up and behind the 175A breakers. Neatness helps but the GSLC often starts looking like spaghetti.

The extra N-G bonds will create undesirable current return paths in case of a short, which could be a shock hazard. On the off-grid VFXR system where the generator also had a N-G bond it caused a malfunction of one of the inverters. On the house, we bought the "home inspector" specifically stated the N-G bonding was correct. When one of my AFCIs had an issue, I dug into N-G bonding and found that the sub-panel in the house had N-G bonded, the panel on the outside of the house had N-G bonded and the service entrance also had the N-G correctly bonded. After removing the two N-G bonds inside and on the house, no more AFCI trips.

clarkef
Forum Virtuoso
Posts: 76
Joined: Wed Oct 31, 2018 9:43 am
My RE system: Radian 8048A w/PV GSLC
FM100 CC x3
10KW of 72 cell panels (5S3P x2)
1600AH (usable) of Li-Ion modules @48v with SIMP-BMS
Midnite Combiners, SPDs
MilSurp MEP-802A ‘5K’ Generator
Location: South Central KY

Re: Generator backup

Post by clarkef » Fri Feb 14, 2020 7:06 pm

Swampdog wrote:
Fri Feb 14, 2020 2:00 pm

From generator specs:
Rated Maximum Continuous AC Load Current:
At 120 Volts . . . . .45.8 Amps
At 240 Volts . . . . .22.9 Amps
[SNIP]
"If you try it and you get too much sag as the Radian tries to balance a new load demand, lower the limits to leave more generator ‘headroom’." (no idea what "sag" and "headroom" are)
I would set generator AC limits to 22.9 or the next lower value if that what the unit supports for continuous operation. .


Sag relates to voltage dropping as a sudden load is applied to the generator which slows down until the governor can apply enough added fuel to deal with the load. If the generator is out of headroom, it will not be able to regain speed unit IL load is removed.

Headroom means the ability of the generator to handle temporary surges in demand beyond the current load. That headroom means if there are 22.9 AAC in load that a pump starting up and pulling above the continuous rated output can be supported by the generator without sagging or dragging the engine speed down. You can make headroom by reducing the AC Charger Limits leaving output capacity unused for new or sudden demands.
Last edited by clarkef on Sat Feb 15, 2020 4:52 am, edited 1 time in total.

Swampdog
Forum Guru
Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Fri Feb 14, 2020 7:25 pm

OK... clear... thanks. So... again... what do I need to shut down to not kill myself when cirrecting tge bonding connections?

S/D

fcwlp
Forum Guru
Posts: 345
Joined: Wed Jan 22, 2020 9:40 am
My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: Generator backup

Post by fcwlp » Fri Feb 14, 2020 8:56 pm

Swampdog wrote:
Fri Feb 14, 2020 7:25 pm
OK... clear... thanks. So... again... what do I need to shut down to not kill myself when cirrecting tge bonding connections?
Follow the Quick Start guide on how to do a shutdown and then use a meter ($10 meter is adequate) to verify that there is no voltage between any of the three AC buss bars and neutral. Should be similar to when you installed your FNDC. If you have an external battery disconnect it is also a good idea to open it so that the 48V is not on the positive buss bar which is near where you are working.

Swampdog
Forum Guru
Posts: 114
Joined: Tue Feb 19, 2019 4:23 pm
My RE system: 7.0 kw system
25 x Solarworld SW280 w/SolarEdge Power Optimizers
12 x 220 GH Energycell
Outback GS load center GSLC175-PV-120/240
Outback Radian 8048a
Outback MATE3s
Outback HUB
Outback FlexNet DC
SOLAREDGE SE6000A-US
Briggs & Stratton Elite 5500w generator (8,500 surge; manual connect)

Re: Generator backup

Post by Swampdog » Wed Feb 26, 2020 3:31 pm

Bonding connection issue: Well... I did not install the FNDC, it was installed by my original installer. He finally responded to my query with "This is a non issue and has been inspected and finaled.", meaning the County building inspector approved it. I am not confident the inspector was even aware of these connections, as his final inspection appeared quite cursory.

So... is this a critical issue I must address?

S/D

fcwlp
Forum Guru
Posts: 345
Joined: Wed Jan 22, 2020 9:40 am
My RE system: GS8048A, FM80 w/3,600 W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed
I also install and maintain grid-tied and off-grid systems, details will be given for these system if required
Location: 80 miles NE of Phoenix at 5500'

Re: Generator backup

Post by fcwlp » Wed Feb 26, 2020 9:00 pm

Swampdog wrote:
Wed Feb 26, 2020 3:31 pm
He finally responded to my query with "This is a non issue and has been inspected and finaled.", meaning the County building inspector approved it. I am not confident the inspector was even aware of these connections, as his final inspection appeared quite cursory.

So... is this a critical issue I must address?
County building inspectors are not all known for their technical competence. My guess, if he even opened the GSLC cover (mine never have) he would not have recognized what he was looking at. So the county approval is worthless.

I would point out to your installer that he has failed to follow the OB manual, the NEC, and a standard duty of care, and that you will hold him liable for any injuries or equipment failures. In other words it needs to be fixed.

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