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At a party, Beatles song came up." When I'm 64." Debate over fuses started. I contend they are the supreme protection if applied right.
 

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corn-fused
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No doubt, overall, fuses will protect better than breakers.:thumbsup:
i have a doubt. recently i got called to a school that some things werent working. got to the old disconnect and the FUSE was fried from top to bottom. have to admit it was a first
 

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It's a broad sweeping statement !
There are circumstances where they would be correct,
But equally there are times when breakers could be better !
Depends entirely on the situation !
:eek:

P.S. How does this relate to the song ?
 

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Bilge Rat
motors and controls.........
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Yes, in nearly all cases, fuses offer better protection than breakers. But the key is using the proper fuse, (and not just the amp rating).
 

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corn-fused
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c.s., where are you? how does this relate to the song?:rolleyes::001_huh:
 

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No doubt, overall, fuses will protect better than breakers.:thumbsup:
Is there any documented proof to that? I know what your answer will be but does it make sense for millions of homes and businesses to be wired intrinsically "unsafe" by using breakers?
 

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RIVETER said:
Is there any documented proof to that? I know what your answer will be but does it make sense for millions of homes and businesses to be wired intrinsically "unsafe" by using breakers?
Fuses are sop for protecting big money items like drives, motors, and sensitive equipment. Breakers are more than sufficient for some soccer moms sub zero. I wouldn't even be surprised if higher end appliances had fuses in them
 

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Fuses are sop for protecting big money items like drives, motors, and sensitive equipment. Breakers are more than sufficient for some soccer moms sub zero. I wouldn't even be surprised if higher end appliances had fuses in them
Are you saying that BIG motors are more important than a small house? Where is the proof that breakers are unsafe?
 

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RIVETER said:
Are you saying that BIG motors are more important than a small house? Where is the proof that breakers are unsafe?
There's a reason why lots of manufactures of the things I listed REQUIRE their products be protected by fuses over cbs. Breakers are perfectly safe I never implied they weren't but in many situations outside of the residential world fuses will be the better choice
 

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Questioner of Authority
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It's a broad sweeping statement !
There are circumstances where they would be correct,
But equally there are times when breakers could be better !
Depends entirely on the situation !
:eek:

P.S. How does this relate to the song ?

When I get older losing my hair,
Many years from now,
Will you still be sending me a valentine
Birthday greetings bottle of wine?

If I'd been out till quarter to three
Would you lock the door,
Will you still need me, will you still feed me,
When I'm sixty-four?

oo oo oo oo oo oo oo oooo
You'll be older too, (ah ah ah ah ah)
And if you say the word,
I could stay with you.

I could be handy mending a fuse
When your lights have gone.
You can knit a sweater by the fireside
Sunday mornings go for a ride.

Doing the garden, digging the weeds,
Who could ask for more?
Will you still need me, will you still feed me,
When I'm sixty-four?

Every summer we can rent a cottage
In the Isle of Wight, if it's not too dear
We shall scrimp and save
Grandchildren on your knee
Vera, Chuck, and Dave

Send me a postcard, drop me a line,
Stating point of view.
Indicate precisely what you mean to say
Yours sincerely, Wasting Away.

Give me your answer, fill in a form
Mine for evermore
Will you still need me, will you still feed me,
When I'm sixty-four?

Whoo!
 

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Estwing magic
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Is there any documented proof to that? I know what your answer will be but does it make sense for millions of homes and businesses to be wired intrinsically "unsafe" by using breakers?
They're called time/current curves. A cheap plug fuse has faster clearing time during short circuit than a circuit breaker. Breakers aren't unsafe, fuses are just safer.
 

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Estwing magic
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For short circuit protection a fuse is almost always better. A current limiting fuse will open within the first half cycle. A circuit breaker will allow multiple cycles before opening.

Selective coordination is safer and easier with current limiting fuses. With a fused system, you can usually selectively coordinate and stay within the first half cycle clearing. This is impossible with circuit breakers. If, for example, a circuit breaker allows ten cycles before clearing in order to coordinate with a downstream device, that's twenty peaks compared to less than one peak for a fuse (although the first peak is the highest and peaks become smaller as arcing within the device disappears).

Fuses are also the cheapest way to protect against fault currents above 10KA. Sure, you can put fuses ahead of breakers to limit the fault current but you have likely lost your system coordination.

The only reason breakers are popular is because they have a built in on/off switch and you don't have to change them (??) after they have interrupted a fault. There's an IEEE document somewhere that talks about testing or replacing a breaker after it has opened under short circuit conditions.
 

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Fuses are sop for protecting big money items like drives, motors, and sensitive equipment. Breakers are more than sufficient for some soccer moms sub zero. I wouldn't even be surprised if higher end appliances had fuses in them
almost all appliances small or big have insides fuses, this is required by UL to protect inside wiring and components (wiring inside small appliance may be 22 awg and pcb board can't be directly on a 20A circuit)
i have manufactures some custom panel to be certified by CSA (in canada) and they are very strict on fuses rating (breakers also accepted but cost more anyway)
 

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Salty Member
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There's a reason why lots of manufactures of the things I listed REQUIRE their products be protected by fuses over cbs.
Yes, fuses are much cheaper for the same level of protection.

Also UL charges for each approval so they go with just fuses.
 

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Salty Member
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almost all appliances small or big have insides fuses, this is required by UL to protect inside wiring and components (wiring inside small appliance may be 22 awg and pcb board can't be directly on a 20A circuit)
i have manufactures some custom panel to be certified by CSA (in canada) and they are very strict on fuses rating (breakers also accepted but cost more anyway)
You kind of contradicted yourself, you say they are required when actully OCP is all that is required and fuses are just a design decision.
 
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