Surge Arrestor Install Help

[Jay M]

I bought a whole house surge arrestor which is installed via a punch-out in my service panel. The instructions for installation are leaving me a little confused:

INSTRUCTIONS Connect black wires to lines load-side of fuse/breaker. Connect white wire to neutral/ground. Warning - To reduce the risk of fire, electric shock or personal injury, this secondard surge arrestor shall be installed in conjunction with a disconnecting means which shall consist of a manually operable Listed circuit breaker that has an interrupting rating sufficient for the nominal circuit voltage and the current that is available at the line terminals of the secondary surge arrestor.

I don't fully understand the language of the instructions, but the electrican who mailed it to me told me to just attach the two black conductors to a double breaker. He suggested using the 30/30 breaker used for my AC. As I recall, he said the white conductor goes to the neutral bussbar.

I can't really see a way to install the surge arrestor in my Service Disconnect box where the neutral and ground have not yet separated, so I must use the SUBpanel. Because this is a subpanel, ground and netural are isolated, so even though the instructions call for a connect to "neutral/ground" will a connection only to neutral buss be acceptable?

I also have a Lightning Arrestor which came with no instructions whatsoever. The electrian said to hook it up the same way as the surge arrestor (to the very same breaker). I do have a 20/20 double breaker which I could use instead of using tripple wires on the 30/30 AC breaker.

Advice and clarification is appreciated.

[Mark or Sue]

Yes, what those instructions said is to put a circuit breaker in front of the surge arrestor. All the units I've seen say to use a 15A double pole breaker. The 30A may be a little large to protect it. I also would not share a breaker with another device, as many breakers are not listed for multiple wires under its screw. The few that are usually require that the wire be the same size and material. So hopefully you have room to add a 15A double pole breaker and connect it to this. If the breaker is listed for multiple wires, put the lightning arrestor and surge arrestor on the same breaker. Your 20A double pole is probably ok too. Also, make sure you're looking at double pole breakers and not tandem breakers. You must use a breaker that takes two bus slots, not two breaker handles sharing a single bus slot.

Also, I would put these arrestors back in the main panel. They are much more effective when they hit an earth ground in a 10 to 20 foot grounding electrode conductor. The odds of this occurring are greatest at the main panel. A subpanel will have a separate ground wire that goes back to the main panel, but it adds length which is bad. Just put both the green and white wires on the neutral bus in the main panel. If you have a subpanel with its own ground rod close to it (unlikely), then the subpanel may be a better location for the surge arrestor if the lightninig arrestor is installed at the main panel - depends on what type of surge you're defending against. Generally, the main panel is the best place. The primary reason for the separate white and green wires is to accomodate main panels that have a separate disconnect box in front of them. After the main disconnect, the ground and neutral must be separate and there may not be room or protective breakers for the arrestors in the disconnect box.

-- Mark Kent, WA

[w_tom]

To summarize what others have said: the connection from that

15 or 30 amp breaker goes through 'whole house' protector, through neutral and ground wire common bus, down wire to earth ground rod. That connection via surge protector to ground rod must not exceed 10 feet, should have no sharp bends, and should be routed mostly separate from other wires (as is practical). The protector must be a short circuit to the ground rod ONLY during the surge. Therefore it must be in main breaker box with a short wire connection to earth ground rod.

Appreciate that a surge protector is not surge protection. Surge protection is the earth ground that all incoming utilities connects to. That surge protector only makes the connection to surge protection - earth ground - during the surge. The shorter that connection, then the better that surge protection 'system'. Most critical component in that 'system' is the earth ground - which is why 'whole house' protector should be in breaker box directly connected to earth ground.

An earth surge goes from each circuit breaker, through surge protector, to earth ground rod. Wire > I bought a whole house surge arrestor which is installed via a

[Mark Wilson]

Hey Mark, it's me Mark Wilson who you helped before. My roomate Jay was using usenet and I forgot to change the name back. I did read your reply to my surge arrestor post a while back, but I couldn't reply due to ISP problems so I thought it was easier to start over. Just want to say thanks for before and thanks for all your help with my service disconnect /subpanel issues. (I'm the guy with the 100amp disconnect going to the 200amp subpanel). Thanks to you and Volts and others, I think I've got everything pretty much in order and actually up to modern code. You'd be shocked (no pun) to find how many many people kept giving me bad information. It wasn't until I had the electrician go back and check the book that he finally agreed with me about what had to be done. And it's here that I got the right info.

Anyway, thanks.

Sounds good. I have room in the box, so I'll just go buy a double 15/15 breaker (both bus slots) rated for accepting two conductors. One problem... the ligthning arrestor(12) is a slightly larger gauge than the surge arrestor(14). I think I'll use them both in the same breaker anyway.

Well, the ground wire going from the Main to the Sub is about 3 feet lug-to-lug. I'd say that (via the main panel) the ground rod is within 20 feet. I'm not sure if you remember me, but my main panel is nothing more than a box with ONE 100amp breaker in it. Everything just goes in and comes out again. There is no room for any other breakers or anything and I'd be lucky to find room on the neutral/ground bar. It's pretty much just a disconnect box using a breaker instead of just a handle. I could replace this box, but it would be too much trouble, partly because I'd have to get the Power Co to shut off power at the meter.

Hmm... My surge arrestor only has two black wires and one white. Only 3 conductors. No ground. The same is true of my lightning arrestor. Does this mean they can ONLY be used in the main panel?

Thanks

[w_tom]

Code requirements says the protector must be via a disconnect means - ie. circuit breaker. You will not have that option in a main box where only a main breaker exists. Put protector in the distribution box so that it can be wired via circuit breakers. Or you could install a second distribution box, with one dual breaker, attached closer and directly to the main box - so that the connection is shorter.

Larger 'whole house' protectors (more joules) can be used on

30 amp breakers. Your breaker size should be listed in the instructions. Most usually call for 20 amp breakers. But instructions will provide manufacturer's acceptable number.

Earth ground may be farther away. So be it. At least it is better than noth> Hey Mark, it's me Mark Wilson who you helped before. My roomate Jay

[Mark or Sue]

If they both use stranded wires and the breaker has one hole (such as Cutler Hammer CH), twist them together tightly and screw it down as a single large wire under the breaker screw. The GE style breaker has two humps, so put a wire under each hump if you have that type. You can use a wire nut and pigtail, but the goal here is to keep all wire runs as short as possible. Or put each on its own breaker if you have the room and unused breakers.

In this case, you'll need to put the arrestors in the inside loadcenter and not in the disconnect box.

For some reason, I thought you had both white and green on the arrestors. Doesn't really matter though, just put the wire on the appropriate bus, which is the neutral bus for a white wire. They will still work in a subpanel. My TVSS has both white and green wires and I don't really know why. At your disconnect, the white and green are tied together, so you shouldn't ever have any voltage difference between those two wires for a TVSS to shunt. For mine, I just get two paths to ground -- one through a white wire and another through a green wire. I don't know what was done inside the TVSS to see if this helps or matters.

-- Mark Kent, WA

[Mark Wilson]

Thanks Tom. I appreciate the reply. I didn't realize the conduit could actually hinder the flow. Interesting. In my case there is no metal conduit, so I'm okay.

[Mark Wilson]

Well, one is stranded, one is solid. I do have GE, but I don't understand what you mean by two humps. I should be able to figure something out. I'd rather avoid the wire nut if possible, and I'm going to try to avoid adding more than one breaker. Thanks for the tips.

OK, that's what I'll do.

Hmm. Maybe the 4 wire arrestors (2black/1green/1white) are made for subpanels and the 3-wire are intended for main panels? No matter, I'll just wire as you suggest and be done with it.

The only thing I'm a little foggy on is the breaker size. I've checked both devices and even visited their respective manufacturers' webites, but no where anywhere is there ever mention of what amp breaker to use. The only thing I've found are diagrams showing black to black and white to white. Tom W says 20-30 amps, you say 15. I'm not sure which is best, but I get the feeling it's not too critical.

Thanks (again) for you're help. I'll pick up a breaker next time I'm at the hardware store.

[w_tom]

Originally stated purpose of breaker is so that protector could be replaced safely without turning off all household power. Don't know if breakers must be sized for their UL1449 certification. If not, then breaker size would be irrelevant

- which would expla> Hmm. Maybe the 4 wire arrestors (2black/1green/1white) are made for