Author Topic: Surge Protector Wiring  (Read 1486 times)

labusker

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Surge Protector Wiring
« on: September 18, 2019, 11:34:36 AM »
What is the proper way to connect the positive wire from the surge protector to the positive side of the circuit in a MNPV3, MNPV6, or MNEDC125 box. There are no positive bussbars in these to make that connection.
Off Grid DIY, Adjustable Ground Mount, 2S3P 375W Mission Solar, MNPV6-Disc, MNDC125, Classic 150, Aims 48V Inverter/Charger, 8 370Ah Duracell 6V batteries in series

Vic

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Re: Surge Protector Wiring
« Reply #1 on: September 18, 2019, 12:47:12 PM »
One common method of connecting an SPD to the positive,  or line circuit,  is to add a breaker,   and connect the hot SPD wire to this breaker,  if there is a spare breaker position available.  The SPD wire will be the only connection to the added breaker.

Some of the recent Combiners may have an extra hole in the positive busbar,  for an added machine screw/nut in the buss.   A ring terminal could be crimped onto the SPD's hot wire,  and this terminal connected to the screw that was added.

IMO,    Vic
« Last Edit: September 18, 2019, 01:08:51 PM by Vic »
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

labusker

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Re: Surge Protector Wiring
« Reply #2 on: October 10, 2019, 11:12:28 AM »
I am not getting reply notices in my email. Is this possible?
If the SPD was connected to a breaker 1st, then if that breaker was off somehow, then I guess the SPD could not do its job!
I would rather put the SPD inside near the controller in the MNEDC175. Does it matter what side of the controller it is put, input or output?. If its on the input, then what is the proper way to connect the SPD without a positive busbar?
Off Grid DIY, Adjustable Ground Mount, 2S3P 375W Mission Solar, MNPV6-Disc, MNDC125, Classic 150, Aims 48V Inverter/Charger, 8 370Ah Duracell 6V batteries in series

ClassicCrazy

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Re: Surge Protector Wiring
« Reply #3 on: October 10, 2019, 11:58:07 AM »
I am not getting reply notices in my email. Is this possible?
If the SPD was connected to a breaker 1st, then if that breaker was off somehow, then I guess the SPD could not do its job!
I would rather put the SPD inside near the controller in the MNEDC175. Does it matter what side of the controller it is put, input or output?. If its on the input, then what is the proper way to connect the SPD without a positive busbar?

Me - I would just put it in the terminal with the larger wire and they will be tightened together and the electrons won't care .

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie

Vic

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Re: Surge Protector Wiring
« Reply #4 on: October 10, 2019, 01:09:01 PM »
Hi lab..,

The SPD  for the PVs needs to be as  close  to the PVs,  as it can  be.  At the PV Combiner is the best place for it.

The standard practice,  is to use a MNEPV breaker  inside the Combiner (or,   for an AC panel,  a breaker is often used,  and is Code IMO).

There should be no reason,   whatsoever,   that an MNEPV breaker would switch itself off.   Even seems unlikely that in the event of a close-by lightning strike,   that this breaker would trip.   The SPDs have an internal fuse,  to protect it from MOVs shorting,  from a large surge event.

Believe that using a screw and crimp terminal for the connection to the bussbar in the Combiner,  should pass inspection.

Most wire connection terminals are not rated for multiple wire/cable connections.  Would probably work  fine in most situations,  but,  believe that this is not Code compliant  --  considered unreliable.

Opinions from someone who is NOT a Code wizard.   Vic
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

Vic

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Re: Surge Protector Wiring
« Reply #5 on: October 10, 2019, 05:55:43 PM »
I am not getting reply notices in my email. Is this possible?

Under "Profile"> Account Settings,   do not  see an  option for  e-mail notification  on Replies.

There  may be a  way,   but do not see  it.    FWIW,   Vic
« Last Edit: October 10, 2019, 05:57:53 PM by Vic »
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

labusker

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Re: Surge Protector Wiring
« Reply #6 on: February 01, 2020, 05:41:57 AM »
if a SPD is wired through a breaker and that breaker is off due to being tripped, during maintenance, etc., then I would think the SPD would not function properly. Your thoughts.
Off Grid DIY, Adjustable Ground Mount, 2S3P 375W Mission Solar, MNPV6-Disc, MNDC125, Classic 150, Aims 48V Inverter/Charger, 8 370Ah Duracell 6V batteries in series

bee88man

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Re: Surge Protector Wiring
« Reply #7 on: February 04, 2020, 11:16:45 AM »
if a SPD is wired through a breaker and that breaker is off due to being tripped, during maintenance, etc., then I would think the SPD would not function properly. Your thoughts.
Could then use a fuse holder..maintenace shouldn't interfer then...

mike90045

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Re: Surge Protector Wiring
« Reply #8 on: February 05, 2020, 12:59:57 AM »
It all depends on what you intend the SPD to protect, and you wire it to the side of the breaker that wants protection.   
http://tinyurl.com/LMR-Solar

Classic 200| 2Kw PV, 160Voc | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph )| Listeroid 6/1, st5 gen head | XW6048 inverter/chgr | midnight ePanel & 4 SPDs | 48V, 800A NiFe battery bank | MS-TS-MPPT60 w/3Kw PV

labusker

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Re: Surge Protector Wiring
« Reply #9 on: February 05, 2020, 10:06:07 AM »
Can a classic 150 be protected if the surge protector is wired on the positive side of a breaker with the classic on the negative while the breaker is tripped? I am wiring the protector in the MNDC125 and to put it on the classic side of the breaker requires using a wire nut on my 8 awg wire. Is a wire nut good enough?
Off Grid DIY, Adjustable Ground Mount, 2S3P 375W Mission Solar, MNPV6-Disc, MNDC125, Classic 150, Aims 48V Inverter/Charger, 8 370Ah Duracell 6V batteries in series

mike90045

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Re: Surge Protector Wiring
« Reply #10 on: February 05, 2020, 06:28:28 PM »
I would NEVER use wire nuts in a solar or battery application.  There is a lot of long, continuous amps, much more so than household appliances that are off more than they are on, solar is on for 4 hours at full power and who ever oversizes the wires !!
http://tinyurl.com/LMR-Solar

Classic 200| 2Kw PV, 160Voc | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph )| Listeroid 6/1, st5 gen head | XW6048 inverter/chgr | midnight ePanel & 4 SPDs | 48V, 800A NiFe battery bank | MS-TS-MPPT60 w/3Kw PV

ClassicCrazy

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Re: Surge Protector Wiring
« Reply #11 on: February 05, 2020, 06:44:11 PM »
I would NEVER use wire nuts in a solar or battery application.  There is a lot of long, continuous amps, much more so than household appliances that are off more than they are on, solar is on for 4 hours at full power and who ever oversizes the wires !!

Two issues aren't there  ?  A good non oxidizing connection especially for low voltage . But then there is the physical connection that a wire nut makes and it's heat rating. I have watched some video's where people put all types of various connectors on wires and seriously overloaded them. Wire nuts did not fail even after the plastic on them melted off and that took extreme overloading. But I have seen where a wire nut melted in 120v AC - but the wires were never twisted tight in it so that is why it got hot.

Larry
system one
Classic 150 , 5s4p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system two
Classic 150 ,5s 135 watt Kyocero , 16s Calb 100AH LiFePO4 , Outback VFX 3648 inverter
system three
Midnite KID MPPT 24 DC in to  12 volt AGM batterie