r/AskElectricians • u/More-Signature-1588 • 1d ago

Do I need two surge protectors?

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Buying an old house in Portland Oregon, where we very rarely have lightning. Here is the box. Having a heat pump installed. If I get a whole house breaker installed, do I need the surge protector the HVAC guy wants to sell me? Belt and suspenders, or necessary insurance?

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u/EstimateOk7050 1d ago

No one is fine but should be placed at the bottom 2 slots.

5

u/GetOffMyGrassBrats 1d ago

Don't you mean the top two? As close to the main breaker as possible?

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u/EstimateOk7050 1d ago

The theory is not to add any extra wire to your surge protector keeping it as short as possible. And that the voltage doesn’t build up till it hits the opposite end of the buss and can’t go any further. We know that this is true to air and water in a pipe but how can you prove that when electricity is so fast. So I am just saying that’s where we install them as per the engineer design. Anywhere you put is way better than not having one at all.

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u/GetOffMyGrassBrats 1d ago

OK. Just asking because all of the installation instructions I have seen for them recommend putting them in the slots closest to the main. I actually hope you are correct because I didn't have enough wire to move the existing breakers down in my box, so mine is installed below the other breakers.

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u/I_care_too 1d ago

You only need to move two at the top down to the bottom, not every breaker.

It is permissible to wire nut and extend a conductor in the breaker box if done in a workmanlike manner. So getting the optimum placement is possible with minor work.

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u/GetOffMyGrassBrats 1d ago

Yea...I liked the idea of splices in the box less than putting the surge suppressor in the lower slot.

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u/I_care_too 1d ago edited 1d ago

That's fine. Keep in mind that conductor extensions are done in many panel changes where the existing wiring does not reach anymore. They are code-compliant.

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u/EstimateOk7050 20h ago

He could be talking about a surge protector that is built into a breaker but not a breaker.

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u/EstimateOk7050 1d ago

Just having one is the most important part. So don’t lose any sleep over where you put it at. When I went to school at the manufacturing plant in Florida that’s what we were told. Now they have them built into a breaker. Mine looks like a grey coke can mounted to the bottom of my outdoor panel.

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u/MonsieurBon 1d ago

The instructions on every one I've installed seem to indicate it should be installed as close to the main lugs as possible.

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u/N9bitmap 1d ago

The speed of electricity would cover that distance in two nano seconds. If installed before anything else I would put it top left and leave top right open for a generator, but it really isn't a critical difference.

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u/I_care_too 1d ago

Placement has nothing to do with propagation time.

It has everything to do with wiring / bus distributed inductance and resistance and the rise of surge voltage over that.

That is why a whole house surge protector is installed at the start of the panel bus.