Author Topic: Spd300 ac sends volts thru from ac out to ac in?  (Read 300 times)

The Ugly One

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Spd300 ac sends volts thru from ac out to ac in?
« on: March 26, 2020, 01:22:31 PM »
So I was installing an complete system and I had all my inbound breakers shut off on the system. My spd-300 ac was wired in properly. I wired my cord onto the panel after I wired the spd in place. Turned thebsystem on to put power to the house. Off grid system battery power. So I was wiring the cord onto the panel for the generator in. All good. So I was then working the plug end onto the cord. Mind you I have the breakers for ac-in flipped off. The neutral touches the positive, which should not matter because everything is in the off position that the cord is wired to. It arc and killed thebspd device. So here is my real problem. Why am I getting power still on the ac-in port? The plug is not connected to anything and the breakers are all off? The spd is transferring 91v ac over to the other side of the panel board? Why is this even available for people to buy? And if this is how the spd works, then what is the point of connecting it up to my inverter because it is introducing power to both sides of my inverter if that is the case? I am used to getting shocked, it is just a little tingle in the fingers, but the $100+ it cost me because it is sending power to the ac-in. Also now since it has shut off the blue light on the devise it still is passing 91v of ac current thru it from the ac-out panel thru the spd and back to the ac-in.

That is my question.

Please inform me and everyone else to why so we all learn from my do's and dont's.

Thanks
The Ugly One
« Last Edit: March 28, 2020, 12:48:26 AM by The Ugly One »
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

Vic

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #1 on: March 26, 2020, 02:13:57 PM »
The Manual:

http://www.midnitesolar.com/pdfs/SPD_Installation_Manual.pdf

Switch OFF,   ALL breakers in a panel when working on it.   Switch the main disconnect,  and all other sources of power,   before doing any work on any power system.

EDIT,  from the above SPD manual,
  "  …    DANGER: Electrical shock or burn hazard. Installation of this SPD should only be done by qualified personnel. Failure to lockout electrical power during installation or maintenance can result in fatal electrocution or severe burns.   …   "<

If you are not comfortable with your knowledge,   or competence,   hire a competent,  Licensed Professional.

Did not exactly understand what happened,   but it seems that  you made several mistakes.

Just all IMO.   Please DO be careful.   Power systems can KILL !   Vic 
« Last Edit: March 26, 2020, 04:24:36 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!

ClassicCrazy

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #2 on: March 26, 2020, 02:22:50 PM »
Can you make a line drawing of your system and how all that stuff is wired in - kind of hard to visualize what might have happened from what you described.  Make a drawing and you can always take a photo and attach that on here in case you don't have another way to display it. Much easier to understand by looking at a schematic or line diagram.

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

The Ugly One

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #3 on: March 26, 2020, 05:06:28 PM »
I will and upload it.
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

boB

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #4 on: March 27, 2020, 02:37:16 AM »

The SPD300 should not start conducting until over 450V DC across either of the two hot lines and GND.

Before this, there may be a wee bit of leakage at some voltage below this.  It may be enough to measure with a high input impedance volt meter but very very little current should be available until a fairly high voltage.

Looking at your hookup, as the others are wondering about, may give a clue.

If the SPD was fully conducting at 120VAC or 240VAC across it then maybe it really is defective ?  That would be very rare but not impossible.  We get VERY few SPDs back.

K7IQ

Vic

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #5 on: March 27, 2020, 11:24:40 PM »
Hi again T U O,

While we await your diagram to be Posted,   would like to mention several additional things:

It seems important to mention,   that,   AC voltages that are present inside panels and boses of our power,   can be dangerous,   and can KILL,

DC Voltages in our PV-based power systems can be considerably MORE DANGEROUS,   than the AC voltage present in most residential power systems.   This is because DC voltages above about 50 V can cause muscle contraction,  when we contact them.   This contraction often makes it difficult for we humans to disconnect our bodies from the sources of this DC voltage.

AND,  it only takes a relatively small amount of current flowing through our chests to stop our hearts from beating.   This can be lethal.

We do not know what is the PV voltage that is connected to the Vin of your Classic 250 CP,   but on a 48 V system,   this is often 85 - 105 VDC at String Vmps,   on a Classic 150.  Classic 250s,   usually run higher Vin values.   At these voltage levels  it can be quite easy for DC currents that flow through our bodies,   to reach lethal levels.

It appears that you envision a fairly large power system,   in your future.   Would suggest that you seek some expert advice,   for the design,   and construction  of that system.

Please DO shut off ALL power sources,   when doing any work on any power system.   There are enough other risks to our lives,  without adding more risks,  by servicing power systems that are not shut off properly.

It is not possible to know exactly what happened when you were trying to wire the cord,  that you mentioned in the first Post,   but,  it seems that you were working in a HOT panel/box.

Take care,   Good luck,    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!

The Ugly One

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #6 on: March 28, 2020, 04:49:13 PM »
My phone wont allow me to upload onto this site. What do I need to do to upload image?
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

ClassicCrazy

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #7 on: March 28, 2020, 07:23:41 PM »
I am doing this on a computer so not sure how it looks on a phone but at the bottom of the Post Reply screen there is a small + that says Attachments - I click on that and can then attach a photo . If you tried it and it says your photo is too large , go into the option of your camera and make the resolution of the photo smaller take the photo again and then try attaching it.
Larry
« Last Edit: March 28, 2020, 07:25:14 PM by ClassicCrazy »
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

The Ugly One

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #8 on: March 30, 2020, 04:48:42 PM »
So here is the schematic what I have installed so far. There is no classic 250s yet, we are waitting for the solar panel mounts to arrive.
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

The Ugly One

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #9 on: March 30, 2020, 04:54:19 PM »
Here is the plug end that goes into the epanel for the generator input.  So this end would be plugged into the generator.
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

boB

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #10 on: March 30, 2020, 05:32:58 PM »

Hey Ugly...  (that doesn't sound very nice ?!?)

I see from your drawing that your SPD  (component I)  is connected correctly BUT I am not sure why you are using one half of the SPD for L1 input and the other half of the same SPD for the L1 output ?   Not sure why you are using an SPD for ANY of the AC outputs ?

Typically one would use a single SPD for just the L1 and L2 input lines to GND.

OK, that being said, (obviously :), the system  GND should be connected at some place to the L1 and L2 NEUTRAL line.   That connection itself should stop any leakage from input to output side  (I think)  since the center (GND/NEUTRAL) is the tie point internally of the SPD for the two halves.

Are you sure that the GND and Neutral are tied together ?   And when you get the "tingle", where are the two connections you are getting the tingle from ?   L1 output  to  ???...     GND or Neutral or bare-foot on a cement floor ?

Usually you won't need to lightning protect the inside of the house...  Only the AC lines coming in from the outside  where lightning can get in.

But, I am wondering why you would would read that leakage voltage because of the  center connection to GND/NEUTRAL.

K7IQ

Vic

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #11 on: March 30, 2020, 06:11:45 PM »
Hi boB,

A couple of things:

The SPD Manual shows one half of an AC SPD connected to the AC IN,   and the other half to the AC OUT  (Fig 1.2).

And,   for some reason,  in the diagram below the above Figure,  it also shows a 240 VAC system,   where this also done (1/2 of an AC SPD connected to AC IN,  the other half to that Line's AC OUT.

Personally would wire 240 VAC system SPDs as you noted,  boB  --  one SPD on L1 & L2 IN,   and another SPD on L1 & L2 on the Output,  if needed.

The inverter in this system appears to be a Sunny Island 120 VAC inverter (FWIW).

As an aside,   MOVs are relatively Capacitive,  which is probably toe origin of the leakage current.

FWIW,    Vic
« Last Edit: March 30, 2020, 09:30:22 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!

The Ugly One

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #12 on: March 31, 2020, 04:14:29 AM »
I believe I was touching the L1 in wire when I was gripping the plug to tighten down the screws. Then when I put the neutral line to slide into the plug it completed the circuit causing me to feel the tingle.

But my question is still that of why is it connecting the L1 out line to the L1 in line thru the internals of the spd?
System 1: / si-6048-us-10 / 2x classic 250 cp / MNE250SMA-OG-SINGLE / 8x trojan deep cycle 420 ah
Extra equipment to put to use:
8x classic 250 cp / 1x classic 250 full edition / 2x si-6048-us-10 / 3 chinook200-48v / 3x 48v 510ah forklift batteries / 90x talesun tp660p-270 watt / 30x 275watt sunita

FNG

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #13 on: March 31, 2020, 08:29:53 AM »
My theory here, This is only a theory.

I do not see a Neutral to Ground bond and if not the Ground will be pulled high by the SPD. If this is off grid you should put a bond between the AC Neutral and Ground


boB

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Re: Spd300 ac sends volts thru from ac out to ac in?
« Reply #14 on: March 31, 2020, 04:02:05 PM »
My theory here, This is only a theory.

I do not see a Neutral to Ground bond and if not the Ground will be pulled high by the SPD. If this is off grid you should put a bond between the AC Neutral and Ground


Maybe the documentation needs to have a sequence of connecting the bonded Neutral green wire connected first ?



K7IQ