Question about FLEXnet relay for pair of FX inverters

An area for discussing the OutBack FLEXnet DC product.

Moderators: OutBack, OutBack Moderator Team

Post Reply
Onfoot
Forum Guru
Posts: 145
Joined: Tue Dec 21, 2010 9:48 pm
My RE system: 2 FX 3048T inverters in parallel.
1 Flexmax60 and 1 Flexmax80 Charge Controllers for solar array.
1 Midnite Solar 4000 Watt AC clipper for wind turbine
1 Midnite Solar Classic 250 Charge Controller for wind turbine
1 Hub 10.3,
1 Mate3s
1 FLEXnet DC
8 Simpliphi 3.5kW LiFePo batteries
18 Helio 255W solar panels on 3 racks--4590W feeding Flexmax 80
12 250 LG solar panels on 2 racks--3000W feeding Flexmax 60
2.5kW Proven Wind Turbine on 90' Tower feeding Midnite Sun clipper and Classic 250 charge controller
6kW, Single phase Newage Stamford generator on Kubota 905 Diesel
Location: Whitehorse, Yukon, Canada

Question about FLEXnet relay for pair of FX inverters

Post by Onfoot » Sat Jan 26, 2019 12:13 pm

I have a pair of parallel stacked FX 3048T inverters. As I get ready to swap Simpliphi 3.5 LiFePo batteries for my 16 year old Surrettes, one suggestion from Outback documentation (cf. p. 6 in this document: http://www.outbackpower.com/component/j ... p-note-pdf) is that the FLEXnet relay be used to control the inverter, as described below:

"For fast discharge applications that donÔÇÖt have the extended LBCO range, or where even the extended LBCO range is not enough due to the five minute delay, there is another solution. The FN-DC relay can be used to detect the voltage drop-off with little or no delay. The relay contacts can then be connected to the INVERTER ON/OFF terminals to turn the inverter off and prevent the batteries from being completely discharged. The settings that have worked under test conditions in the OutBack test lab are listed in Table 2. These can be tailored for the best results for a given application. Connection points are identified in the figure to the right."

I am not sure if this will be relevant to me, but it does seem like a safeguard to consider. But with a Master and a SlaveOB1 set of inverters, if the Master is controlled as described above, would not the Slave kick in? Perhaps an ignorant question, but grateful for benefit of experience and wisdom greater than my own.

Thank you.

Mike Curran
Forum Emperor
Posts: 1089
Joined: Sat Aug 28, 2004 6:28 pm
My RE system: Outback:
- 8 (2x4) Evergreen 180's into one MX60 (2007)
- 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: (2012)
- 30 (2x15) 235W panels with Enphase M215 microinverters, grid-tied.

All self-designed and self-installed
Location: Chagrin Falls, Ohio

Re: Question about FLEXnet relay for pair of FX inverters

Post by Mike Curran » Sat Jan 26, 2019 1:47 pm

I've been searching the FX manual for an answer but so far, nada. I'd bet that the slave would follow the master if the master is shut off but don't know for sure. Easy way around this (barring somebody else knows the answer) is to use a double pole relay, that is, with 2 sets of contacts, one for each FX on/off switch. Then you'd get sure to shut both off when the FNDC detects low voltage.
http://www.tigoenergy.com/site.php?95b2dca2-ca6c
https://enlighten.enphaseenergy.com/public/systems/Hctc107221

jbakker
Forum Guru
Posts: 169
Joined: Fri Feb 23, 2018 6:47 am
My RE system: 2 VFX3648 Inverters 2 FM60 150VDC Charge Controllers Mate3 3.4 KW of panels 15kw JC Onan NG Generator made in 1975 I love that generator almost as much as my wife.
7 banks of 14 cells each from a 2017 Chevy Volt. Parallel for the AMP Hour. 7 Chinese made BMS systems.
Location: Goderich Ontario Canada

Re: Question about FLEXnet relay for pair of FX inverters

Post by jbakker » Sat Jan 26, 2019 8:04 pm

A double pole realy like Mike suggestec will do the trick.
I am aslo pretty sure that the salve will follow the master if you just open the wire from the on/off on the inverters.
I will double check this in the moring on my system. I am on grid casue I ahve niot seen 2 days of straight sun in long time.
I will let you know the results.

Onfoot
Forum Guru
Posts: 145
Joined: Tue Dec 21, 2010 9:48 pm
My RE system: 2 FX 3048T inverters in parallel.
1 Flexmax60 and 1 Flexmax80 Charge Controllers for solar array.
1 Midnite Solar 4000 Watt AC clipper for wind turbine
1 Midnite Solar Classic 250 Charge Controller for wind turbine
1 Hub 10.3,
1 Mate3s
1 FLEXnet DC
8 Simpliphi 3.5kW LiFePo batteries
18 Helio 255W solar panels on 3 racks--4590W feeding Flexmax 80
12 250 LG solar panels on 2 racks--3000W feeding Flexmax 60
2.5kW Proven Wind Turbine on 90' Tower feeding Midnite Sun clipper and Classic 250 charge controller
6kW, Single phase Newage Stamford generator on Kubota 905 Diesel
Location: Whitehorse, Yukon, Canada

Re: Question about FLEXnet relay for pair of FX inverters

Post by Onfoot » Sun Jan 27, 2019 10:38 am

Thank you, Mike and jbakker. Double pole relay is clearly one option. Still curious about whether Master shut-off will manage the SlaveOB1 also. If you manage to test this, jbakker, post your finding. Thanks!

jbakker
Forum Guru
Posts: 169
Joined: Fri Feb 23, 2018 6:47 am
My RE system: 2 VFX3648 Inverters 2 FM60 150VDC Charge Controllers Mate3 3.4 KW of panels 15kw JC Onan NG Generator made in 1975 I love that generator almost as much as my wife.
7 banks of 14 cells each from a 2017 Chevy Volt. Parallel for the AMP Hour. 7 Chinese made BMS systems.
Location: Goderich Ontario Canada

Re: Question about FLEXnet relay for pair of FX inverters

Post by jbakker » Sun Jan 27, 2019 3:23 pm

So I went out this afternoon and did the experiment to see if the salve would shut off when the master inverter on/off jumper was removed.
I unplugged the connectors off both boards to make sure there were no jumpers connecting the on/off terminals.
Both inverters stayed on.
On my master and slave inverters there is also a little black jumper as well, beside the connector plug that I pulled off earlier. So I pulled both jumpers off.
Both inverters stayed on. I then said WTH and unplugged the MATE3 from the master inverter. Stacking Error came up.
Never unplugged the slave inverter from the mate3, ran out of time. Wife wanted power back in the house.
I did have the house disconnected from the inverters.
Hope this info helps you out.
Does the MATE3 or any other mate control the inverters when connected? I do know that if I dont have a mate on a inverter that I am fixing it will not power up till that jumper is there. Never thought to leave jumper off and plug in mate. On my list of stuff to try. I have the parts to make a 24 volt 3600 watt inverter so I may try that out when I get the time.

Onfoot
Forum Guru
Posts: 145
Joined: Tue Dec 21, 2010 9:48 pm
My RE system: 2 FX 3048T inverters in parallel.
1 Flexmax60 and 1 Flexmax80 Charge Controllers for solar array.
1 Midnite Solar 4000 Watt AC clipper for wind turbine
1 Midnite Solar Classic 250 Charge Controller for wind turbine
1 Hub 10.3,
1 Mate3s
1 FLEXnet DC
8 Simpliphi 3.5kW LiFePo batteries
18 Helio 255W solar panels on 3 racks--4590W feeding Flexmax 80
12 250 LG solar panels on 2 racks--3000W feeding Flexmax 60
2.5kW Proven Wind Turbine on 90' Tower feeding Midnite Sun clipper and Classic 250 charge controller
6kW, Single phase Newage Stamford generator on Kubota 905 Diesel
Location: Whitehorse, Yukon, Canada

Re: Question about FLEXnet relay for pair of FX inverters

Post by Onfoot » Sun Jan 27, 2019 7:23 pm

Jbakker. Apologies to your wife for having to endure power blips. And now I am a bit confused. My system is controlled via Hub and Mate3s, which manages two inverters and two FM CCs. I am adding a DC FLEXnet to the system (waiting for a Hub10.3 to arrive--my legacy Hub is a Hub4). The intention in the OB documentation is that the FLEXnet is able to turn the inverter off more quickly (no 5minute delay). There is a jumper that has to be moved (as per illustration in documentation referenced in my first post) in order for this to work. From what you describe, you clearly did some interesting experiments--but not sure that any of it quite matched the conditions that the documention is describing. I have fired off a note to OB support and will let you know what I hear back. (And very weird that your inverters stayed on no matter what!)

jbakker
Forum Guru
Posts: 169
Joined: Fri Feb 23, 2018 6:47 am
My RE system: 2 VFX3648 Inverters 2 FM60 150VDC Charge Controllers Mate3 3.4 KW of panels 15kw JC Onan NG Generator made in 1975 I love that generator almost as much as my wife.
7 banks of 14 cells each from a 2017 Chevy Volt. Parallel for the AMP Hour. 7 Chinese made BMS systems.
Location: Goderich Ontario Canada

Re: Question about FLEXnet relay for pair of FX inverters

Post by jbakker » Mon Jan 28, 2019 5:33 am

The wife is used to the odd power blip not to worry.
I wish I had more time to mess with the setup. I will see if I get more time this week.
Will be interesting to hear what OB has to say. I to have FLEX NET DC. I do not use it. I need to get a 10 port hub and that's on the wish list.

My battery settings are pretty close to the SimpliPhi ones. I use a higer voltage as i run 14 cells.

Absorb: 57.6
Float: 57.2
Re-Float: 50 VDC
Absorb Time: .1 hours
Cutout 45.6 VOLTS
This equals about 3.25 volts per cell.
I have had it cut out once on me.
Will be a year in March that the volt battery has been in service. The cells are still very well balanced.
The China BMS is working out. 3 more coming.
I charge the pack at 18 AMPS AC input on both units.
Hope this info helps you out.

Post Reply