Secondary Surge Arrester

I’ve never seen these devices before and have no idea if this is a proper installation. Any help would, as usual, be deeply appreciated.

This surge arrestor is wired directly into the double-pole breaker for the dryer (looks like a double-tap in the photo)

Sorry for the blurred pic.


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I have one on my panel. Surgebreaker, it plugs right into both buses(one wire to the neutral bar). Now the one you show appears to be one you install “ON” the panel, usually through a knock out. Then wire back to the buses via a breaker. I do not believe they are to be installed inside the panel, since the status light wouldn’t be visible.

Just a guess. Do you have a make/model?


Make is Square D. Model SDSA1175

Found a recall of the SDT1175.

I’m wondering why it’s on the dryer circuit and is it supposed to be wired into the lugs of the breaker.

I’m guessing those are both questions.

  1. [A guess] Because it was a big breaker.
  2. Since their are small conductors involved, the need ocp & scp. [another guess].



That appears to be a lightning surge suppressor. There are two basic types of residential or light commercial surge suppressors. One type connects to your electric panel where your circuit breakers or fuses are located. These devices are designed to stop harmful lightning surges before they can travel towards the electronic equipment in your home.

I’ve personally never seen a surge suppressor wired into the dryer breaker, but I have seen several suppressors double tapped into the main SE breaker, which is absolutely fine. So in your case the lighting suppressor is only protecting the dryer circuit. And the suppressor itself should be mounted on the outside of the panel.

Called an electrical supply house and the man I spoke to said that his own house was struck by lightning once and it went straight to the dryer and fried it. He was pro-dryer protection.

So I was right on. Make sure it gets moved to the exterior of the panel.

It is supposed to be attached to a two pole breaker. Being attached to the dryer breaker does not mean it is only protecting the dryer, it is protecting both legs of the service via the dryer breaker. It shouldn’t be double tapped though, on that particular breaker anyway.

I believe the breaker size is supposed to match the wire size on the device, if I recall from the installation instructions.


I don’t know if you did catch this or not did you see doubled netual in the neutral bussbar ?? there are few empty slot it can be used SOP is never doubled up netural at all but fine with grounding wire { green or bare as long they are same size }]

But kinda hard to see the photo but is that a BR series Breaker ?? if so i think in that size they are allowed double lugged { i will check my catalog book to verify it }

Merci, Marc

Just protecting the dryer is “false security”.

Example: About 12 years ago, lighting struck a tall tree in the back yard of a residential property about 500 feet down the road from my house. Here’s the results: (1) The owner’s deep well pump got fried, (2) the phone across the street (that, by chance, her daughter was talking on as she babysat) got fried…she got a minor shock, (3) another neighbour’s stereo system got fried, (4) a small colour TV in our master bedroom got fried. I don’t know if other neighbours had problems we never heard of.

Since the lugs for the service entrance cables are only for use with ONE conductor this installation would not be compliant.

Also the dryer circuit would not be the only item protected.

Lightning supressors are absolutely fine tapped into the main. They are not current carrying conductors.

The problem is that the lug is only rated for one conductor, not the lack of overcurrent protection.

I never stated that it was “lack of overcurrent protection”.

I simply stated “Lightning supressors are absolutely fine tapped into the main”.

just checked my old Square D protector:

It says to install across the SEC’s (plus connect to neutral bus) even suggesting to do it as far back as the drip loop. (with AHJ approval). The instructions don’t say to tap in the SEC lugs but that was suggested by the vendor when I bought it. The leads appear to be tinned #12 copper cable so that would not be a big “imposition” at the service lugs. Other newer devices are “plug-in to bus bars & connect neutral” types. Could not find it today but believe I read a few months ago to install these at the top position for branch circuit breakers in the panel (if that’s where the SEC lugs are). It seems that you want to stop the surge before it gets to other circuits farther down the panel.

From a previous post where the protection was installed on the dryer breaker terminals, would it protect all circuits or just the dryer? My feeling is just the dryer. Comments/explanation?

I’m not an Electrician by no means, but every lightning suppressor I’ve ever encountered was tapped directly into the SE lug. I can recall asking about this particular lugging years ago and I can recall Electricians (not sure who) stating that tapping of the suppressor at the SE was fine. Since then, I’ve always seen them tapped in at the SE lug and have never called them out.

If there are other options to this suppressor connection, I’d like to know about them.

The device would be protecting more than just the dryer as it is across the bus when the breaker is in the on position.

Here is the Installation manual.

The vast majority of lightning arrestors and surge protectors I see installed in panelboards are connected to one of the 240 volt breakers. Rarely do I see them at the main lugs or main breaker. Either way will protect the panel, although I can’t imagine anything protecting the system from a healthy lightning strike! :shock:

So…going back to my conversation with the electric supply house person…

The entire panel is protection by connecting to any one (240) breaker? Not just the circuit it is wired to?

Also, I read the directions that Mike provided (thanks - I found brochures, but no instructions) and it says “connections to a branch circuit breaker that has terminals suitable for use with #14AWG wire…”

So, is it possible to have this wired in the lugs of an unused breaker and still operate properly?


This is interesting…From UL
Many people assume that surge suppressors can protect their home from lightning damage. Surge suppressors are not lightning protection devices - they cannot protect your home or your home’s internal electrical wiring from a direct strike. Surge suppressors can, however, protect your equipment from voltage surges caused by unexpected occurrences such as a utility pole downed by a storm.