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Will a whole house surge protector work properly in a sub panel?

Will a whole house surge protector work properly in a sub panel?


  #1  
Old 03-05-23, 02:20 PM
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Will a whole house surge protector work properly in a sub panel?

Afternoon folks..

Three years ago my carrier infinity ecm main blower motor stopped working and I had to replace the sl22 thermistor in the module. Last year the A/C condenser compressor I installed went to ground after 23 years of service.. I'm uncertain if a surge took them out, but with most new appliances lately equipped with boards, I should at least have a whole house surge protector and even better, secondary protection at the appliance.
Problem is that all the breaker spaces in my main 100 amp cabinet have been used, but if I move a few around in my sub panel I would have room. If the wires are long enough, I might even be able to move a few single phase breakers over to the sub panel,

Will a whole house surge protector work properly in the sub panel? I realize a surge protector outside off the meter is not a diy project..

Thanks
 

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03-05-23, 02:24 PM
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That device would protect predominately the sub panel with some residual main panel protection.

Line surges have nothing to do with a defective thermistor/varistor in an ECM motor.
 
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Old 03-05-23, 02:24 PM
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That device would protect predominately the sub panel with some residual main panel protection.

Line surges have nothing to do with a defective thermistor/varistor in an ECM motor.
 
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Old 03-05-23, 02:27 PM
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A whole house surge protector installed in the sub-panel will only protect the branch circuits that originate off the sub-panel. If you want to protect everything you need to install the surge protector in the main panel or before.

If you can make room in the sub-panel relocate two circuits in the main panel to the sub-panel and install the surge protector in the main panel. Or find 4 circuits you can double up in the main panel to make room.
 
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Old 03-05-23, 07:33 PM
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Some manufacturers (at least Siemens) make whole house surge protectors that plug into the panel in place of a two pole breaker, and also include 2 single pole breakers for branch circuits. So you can remove two adjacent single pole breakers, install the surge suppressor, and connect the two circuits to the integral breakers. Bottom line: you get whole house protection without losing any breaker positions.

You'd have to check what brand of breakers are supported by your main panel and see if a similar style protector is available for your panel.

Here's a link to the Siemens version: https://www.homedepot.com/p/Siemens-...SPDP/202562776

 
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  #5  
Old 03-05-23, 11:01 PM
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I have had lightning problems, it hits the line somewhere, the protection devices in the main panel has saved us from fire. (only fire once, and that was before the protection was put in) Still the result are lots of defect electronic devices like fire alarm, phone related units.... To protect really well I guess each unit should have an extra protection. But, if the lightning really hits everything may fail. I feel that to have it in the main panel has saved our house, but of-course it could have went well without it. I'll never know for sure.
 
  #6  
Old 03-06-23, 07:59 AM
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I like to use a baseball analogy for lighting protection:
If a ground ball is hit hard up the middle, the pitcher, second baseman (or shortstop) and center fielder all have a chance to field the ball. But the further the ball travels, the chance of getting the batter out decreases.

The pitcher has the best chance of throwing the batter out since he is closest to the batter. By the time the ball gets to the second baseman, the runner is further down the base path, so the chance of throwing him out is less. By the time the ball gets to the center fielder, the is little chance of throwing him out.
So, the closer a whole house surge protector is to the entry point, the better chance of stopping the surge.

Protection in layers, as d_s_k mentioned, has worked best for me. Whole house plus individual protectors at each point of use. However, if it's a direct hit or even really close, nothing will stop it. Mother Nature can be quite intractable.
 
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Old 03-06-23, 04:39 PM
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phone related units...
Lightning strikes will often travel on phone lines. A whole house surge protector likely will not protect a surge that come in on a phone line. There are phone line surge protectors available.
 
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Old 03-06-23, 11:53 PM
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Yes I forgot to mention telephone lines, we have no such line anymore, nor cable TV.
I had lightning protection on the phone line. (2 glass cylinder fuses) and a spark gap in the line, no sign of the glass at all after the lightning stroke the phone wire around 1 mile away. The touch tone phone did work when I twisted together the wires, but the rotary 1944 phone did, but the hammer had to be re-positioned in the ringer. I love old fashioned technology.

Most US houses has a NID (Network Interface Device) that is the telco's property and it should contain some protective device.
 
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Old 03-07-23, 06:54 PM
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Thanks folks..
I don't get how exactly you can "get whole house protection without losing any breaker position", but Ill take your word for it Carbide..

I have a square D panel and pictures of my breaker style. When I looked at the Siemens surge protector, it does not state if compatible with square D panels, so I assume its only for Siemens load centers? And if you suggest another surge protector, Im the buy once cry once type, and understand you usually get what you pay for..






 
  #10  
Old 03-07-23, 09:29 PM
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GrandScale: Surge protectors. are actually mislabeled. They actually protect home from incoming “transients” on power lines. Most effective installed on main panel.

A simple solution is installing protector on existing main panel 20 amp 240 volt breaker. It draws no current/amps so whatever is powered by breaker will not be affected.

This $88 unit will protect a home for years.

https://www.amazon.com/Square-Schnei...46904643&psc=1

For a better understanding of “surge” protectors see doughess Post #5, 8, 10, 12 in link: surge protectors in the main panel
 
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Old 03-08-23, 03:56 AM
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I took a look at the Square D surge protector you linked to and have the habit of looking at bad reviews first. The first bad review starts out with “burns like a Roman candle”. Although I have experienced a few failures over the years, I have never had a fire yet. Knock on wood. And my panel is inside.
 
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Old 03-08-23, 09:11 AM
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The siemens unit is a combined unit...surge suppressor and 2 20amp breakers in the form factor of a two pole breaker. So you remove two adjacent 20 amp breakers, plug in the siemens unit, and attach the two circuits from the breakers you pulled out to the two breakers in the surge suppressor. Plus you have to connect a neutral wire to your neutral buss.

Having said that, the siemens unit won't work in your square D panel, and Schneider doesn't make a plug in suppressor unless you have a newer panel with plug on neutral, which you don't.

So you are back to putting the suppressor in your sub, or freeing up two breaker spaces in your main.
 
  #13  
Old 03-08-23, 09:21 AM
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How to provide main electric panel protection of home electronic from incoming power issues is complex.

Like lightening protection, there is no ultimate answer. Somewhat like decision on how much life insurance to buy.

DH has used protector for 40 yeas on home panel, high on hill, with past issues.

Since installing protector, after lightening, ceiling light dimmers do not blow keeping lights.

Service life is long on TV, microwaves, and other electronics with semiconductors that power line transients, over ling periods damage,. They all cost more than one protector!

DH personal opinion is waste of money spending more than $100 or 60 KVA for protector. Have long electric/electronic industry experience.
 

Last edited by doughess; 03-08-23 at 09:50 AM.
  #14  
Old 03-08-23, 06:42 PM
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"Having said that, the siemens unit won't work in your square D panel, and Schneider doesn't make a plug in suppressor unless you have a newer panel with plug on neutral, which you don't.

So you are back to putting the suppressor in your sub, or freeing up two breaker spaces in your main."


Sorry, but it sounds like your contradicting yourself Carbide..

Since I can free up two breaker spaces in my main square d load center, will this Square D - HOM250PSPD work?

https://www.amazon.com/Square-Schnei...ustomerReviews
 
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Old 03-08-23, 07:22 PM
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Since I can free up two breaker spaces in my main square d load center, will this Square D - HOM250PSPD work?

https://www.amazon.com/Square-Schnei...ustomerReviews
Nope, that will only work in Square D Homeline panels and you have a QO series panel. The breakers are not interchangeable between the two. Since Schneider doesn't make a plug in suppressor for the QO series, you would have to use something like this:
https://www.amazon.com/Square-Schnei...1MYD45U1&psc=1

It mounts outside your panel and connects to a 2 pole breaker you would install in the 2 slots you say you can free up in your main panel.
 
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Old 03-10-23, 03:31 AM
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Yeah, sorry you mentioned that surge protector before.

I guess I'm not willing to install something that almost caught somebody's house on fire..
 
 

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