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Why does surge protector have to be connected to 20amp breakers?

Why does surge protector have to be connected to 20amp breakers?

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  #1  
Old 11-29-12, 10:57 PM
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Why does surge protector have to be connected to 20amp breakers?

This Leviton 51110 unit specifies it should be connected to 20 amp breakers.

Wondering why so?
 
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  #2  
Old 11-29-12, 11:16 PM
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This Leviton 51110 unit specifies it should be connected to 20 amp breakers.

Wondering why so?
Because they didn't want the breaker to trip under load and take the whole house surge protector offline? Why do you ask?

BTW, are you sure about that?

Originally Posted by Leviton 51110-1 Installation Instructions (emphasis added)
Leads from the SPD must be connected to the power mains through a 30 Amp (maximum) disconnect and fusing means. Either dedicated branch circuit breakers (independent single-pole preferred), or a fused disconnect switch may be used.
 
  #3  
Old 11-30-12, 04:48 PM
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Leads from the SPD must be connected to the power mains through a 30 Amp (maximum) disconnect and fusing means.
The instruction sheet in the box is identical except it says 20 amp not 30 amp.
 
  #4  
Old 11-30-12, 05:37 PM
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Every surge protector has a maximum rating that determines how big a surge it can suppress. Fortunately the bigger the surge, the smaller the chance of getting one. You decide how big a surge you want to protect against and buy the appropriate sized protector.

Whenever a surge protector is activated, heat is produced because some "excess" current is shunted (shorted if you insist) to ground. The breaker size should allow the surge protector to perform at its maximum capability but not let the surge protector itself get overloaded which can cause a fire.
 
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Old 11-30-12, 05:51 PM
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because some metal oxide varistors fail by shorting. That would be a big problem in an unprotected load center.
 
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Old 12-04-12, 06:35 PM
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because some metal oxide varistors fail by shorting. That would be a big problem in an unprotected load center.
What I was wondering is why 20 amp? Why not 40 or 15?
 
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Old 12-04-12, 07:13 PM
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What I was wondering is why 20 amp? Why not 40 or 15?
You'd have to ask the manufacturer that question. Some specify 20 amp, some 30 amp and even others may specify 15 amp. Some suggest a fused disconnect, some want two separate single pole breakers and may want two pole breakers.
 
  #8  
Old 12-05-12, 07:42 PM
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The MOV's can withstand many times over the face value of the circuit breaker. Like hundreds of amps, just not for very long. So, the manufacture has to work in the window between false trips with the expected breaker timing curve and flaming protective devices.
 
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