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-   -   fuses to breakers (http://www.diychatroom.com/f18/fuses-breakers-12429/)

handyman1355 10-16-2007 02:51 AM

fuses to breakers
 
Hello, I have a house that still has fuse panels, could anyone tell me the cost of replaceing them with breakers. I,m in Ky

Mike Swearingen 10-16-2007 07:50 AM

I am not a professional electrician, just a long-time DIYer and real estate broker.
This cost depends on a number of things, but here in northeastern NC, it usually runs anywhere from $600-$900 to install a new 200 amp residential breaker panel.
Mike

moneymgmt 10-16-2007 09:11 AM

Quote:

Originally Posted by Mike Swearingen (Post 68326)
here in northeastern NC, it usually runs anywhere from $600-$900 to install a new 200 amp residential breaker panel.
Mike

I'm jealous of NC!! 100amp service upgrade in SE Michigan will run more in the ballpark of $800-1200 depending on things like do you have a riser or is the line underground, and how far it is from where it touches the house to the panel itself. 200amp is approx. $200-300 more. Just estimates!

J. V. 10-16-2007 11:06 AM

Get a minimum of three quotes. Get a contract on the price, how long it will take and the brand and size of the panel. Get a 200 amp, 42 circuit panel. Make sure the electrician is licensed.
I like to put the new panel "if possible" in a new location so as to leave the existing one in operation, until the new one is finished. Like right next to the old one. So the branch circuit wires MAY be long enough to reach the new one.

Prices are hard to judge. Thats the reason for the quotes.
Materials are also hard to judge for the homeowners. like the quality of the panel itself. Make sure you get the manufacturer of the panel and report to us. Not all panels are created equally.

Andy in ATL 10-16-2007 02:36 PM

I agree with jv except... you are not gonna get a 200A 42 space panel with a single phase service, it will be 40 spaces. Also, the electrician shouldn't have to put the new panel next to the old one in order to keep everything on. Around here we use a gas powered portable generator for our drop lights, pull the meter, swap panels and re-install meter....2-4hrs. max.

arichard21 10-17-2007 07:27 AM

Quote:

Originally Posted by Andy in ATL (Post 68406)
I agree with jv except... you are not gonna get a 200A 42 space panel with a single phase service, it will be 40 spaces. Also, the electrician shouldn't have to put the new panel next to the old one in order to keep everything on. Around here we use a gas powered portable generator for our drop lights, pull the meter, swap panels and re-install meter....2-4hrs. max.


unless the panel is in such a place that would make it a code violation... ie if it is more than the allowable distance from the point of entry into the structure.

we had to do this at our house, when service was installed in 1923, there wasnt a rule saying how far in the panel could be. when we upgraded, we had to move the panel almost 10 ft closer to the entrance. because it was a semi-diy job (electrician did the meter pan and service entrance and i moved all the ccts from old box to new box), i used the old panel as a sub while i took my time changing everything over.


but all the ccts had to be extended by approx 10 ft, so if a pro was doing it, that would have been another expense.

jogr 10-17-2007 10:11 AM

If you have adequate power already then it would be most economical to replace your fuse box with a breaker box of the same amperage. Then you won't have to replace anything before the box.

Actually, it would be most economical to leave it as it is. There's nothing wrong with fuses.

What is it that you are trying to accomplish with the change? If you are having problems with blowing fuses the new box won't fix the problem.

elkangorito 10-17-2007 10:40 AM

Quote:

Originally Posted by jogr (Post 68561)
If you have adequate power already then it would be most economical to replace your fuse box with a breaker box of the same amperage. Then you won't have to replace anything before the box.

Actually, it would be most economical to leave it as it is. There's nothing wrong with fuses.

What is it that you are trying to accomplish with the change? If you are having problems with blowing fuses the new box won't fix the problem.


Well, that depends upon the type of fuses being used.

If the OP has existing rewirable fuses, there is highly likely to be a big problem. Rewirable fuses (AC1 rated) are not able to safely "blow" on a "modern fault". I now bring your attention to the words "fault" & "modern".

Years ago when consumer load was a lot less, transformer sizes were a lot smaller. This meant that the "prospective fault currents" of such transformers were also a lot smaller than that of modern day transformers. To give you an idea of what I'm talking about, a typical (Australian) 3 phase Star/Delta 150kVA transformer has an impedance of about 4%, which typically means that the "prospective fault current" will not exceed 6 000 Amps (six thousand Amps). Generally speaking, the smaller the transformer, the smaller the prospective fault current. AC1 rated fuses can only safely break a maximum fault of
1 000 Amps. "Standard" circuit breakers for domestic use usually have a "fault interrupt capacity" of about
6 000 Amps (6kA) & will therefore safely open on a fault of up to 6 000 Amps.

BTW, "safely" means that they will not explode.
"Fault" means "short circuit".

On the other hand, if the OP has HRC fuses that are BS88 rated, they will safely open (blow) a fault of up to 200 000 Amps (200kA) & will limit the fault current to about 10 000 Amps (10kA). BS1361 HRC fuses will limit the fault current to less than 4kA for a fuse size of about 80 Amps or less.
"BS" stands for "British Standard".

Unfortunately, it's not just "overload" current that determines what type of circuit protection must be used. "Fault Current" is considerably more important & should be observed at all times.

jogr 10-17-2007 11:03 AM

The OP identified the location as Kentucky. Given his location and the typical terminolgy used in the US, I assumed when he says fuse panel he is talking about the normal screw-in fuses designed for the modern electric grid found in the US. If so, I doubt that the issues you raise are applicable. However, perhaps the OP can clarify what his current equipment is.

elkangorito 10-17-2007 11:13 AM

Quote:

Originally Posted by jogr (Post 68583)
The OP identified the location as Kentucky. Given his location and the typical terminolgy used in the US, I assumed when he says fuse panel he is talking about the normal screw-in fuses designed for the modern electric grid found in the US. If so, I doubt that the issues you raise are applicable. However, perhaps the OP can clarify what his current equipment is.

I fully accept & appreciate what you are saying :) but until someone (the OP?) can verify that "normal screw-in fuses designed for the modern electric grid found in the US" or HRC fuses are in use, my assumption (which hopefully is wrong) is that rewirable fuses are being used & that "fault current" could be a serious issue.

Are the US normal screw-in fuses, HRC fuses or are they the same "US screw-in" type as still seen used in Thailand, which are not HRC?

jogr 10-17-2007 12:05 PM

Here is an example of the type that is typically found in US residential fuse boxes.
http://host1.publiquik.com/bussmann_...i?familyUid=44

Handyman - is this what you have?

Stubbie 10-17-2007 12:27 PM

Handyman.....

If cost is a big issue a nice alternative is edison plug breakers like these....they allow the convenience of a breaker with a screw in base.

http://media.doitbest.com/products/510211.gif




Kangaroo

Edison fuses for home panels are now required to have an interrupt rating of 10KA. And must sustain 135% overload for one hour. I think IEC and BS standards are 150% for one hour. At any rate the time current lag characteristics are vastly different between US standards and IEC and BS so our fuses are not interchangable.

Generally speaking these plug fuses are general purpose in that they are designated type S base and Type T base one having a rejection feature and one not. The rejection feature will not allow you to install the wrong fuse. They will allow motor inrush and are suitabale for lighting circuits and appliance circuits like the kitchen. They are dual element fuses.

I'm not able to find a characteristics on the HRC fuse you speak of so is this a fuse class that is current limiting and inductive load rated?

Our plug fuses will limit the current to 1/2 cycle before opening for short circuit protection.

I don't profess to be a fuse expert so can only tell what I "think" I'm sure of.

Some reference material

T_CWD_Fuses.pdf (application/pdf Object)

http://www.bussmann.com/library/bifs/8005.PDF

handyman1355 10-17-2007 05:42 PM

Yes I have the typical screw in fuse, the reason I was going to up grade is the previous owners have a mess with wireing including a sub panel which is almost full. I have no problem with fuses blowing I would just like to know the wireing is right and safe.

robertmee 10-17-2007 07:21 PM

I just went through the same thing. I replaced a 60Amp service and fuse box with a 200Amp service and 40 slot breaker panel. From my DIY experience, I can tell you that electricians are worth every penny. What would probably take them 6 to 8 hours has taken me 3X that. From research, to collecting materials, to back and forth trips to Home Depot, I have much respect for the electrician. If you decide to go the DIY route, be aware of all the hidden costs and the required tools (some of which I didn't have):

Good pair of wire cutters large enough for 4/0 wire
Good pair of wire strippers
Good pair of lineman's pliars
Torque wrench with allen set
Good Knife or Case Cutter for stripping insulation
Electrical Tape
Various 1/2", 3/4", 1" and 2" panel clamps
SEU 4/0 AL cable
2" Conduit and fittings (You'll have to make your mast bigger)
PVC Cement or Teflon tape (depending on Conduit type)
2" WeatherHead (bigger, if overhead service)
2" Conduit clamps
Ground Rod(s) - Your municipality may require you to drive an additional one
Hammer Drill or Sledge to drive Rod(s)
Ground Rod clamps
Bare copper wire for ground (needs to be bigger)
Clips or clamps to secure ground wire to home
Proper Disconnect if Panel is good distance from Meter
Meter Box
Mounting hardware to secure Box to House
Duct Seal
Tube of Oxidation Inhibitor
200A Panel
Screws to secure Panel to studs
Drywall Saw to make panel hole bigger

And I'm sure I've forgotten several.....

elkangorito 10-18-2007 10:42 AM

Guys...my comments in blue.

Quote:

Originally Posted by jogr (Post 68596)
Here is an example of the type that is typically found in US residential fuse boxes.
http://host1.publiquik.com/bussmann_...i?familyUid=44

Handyman - is this what you have?

Based on the above link & Handymans comment (he says he has these fuses), it appears that they certainly can safely interrupt a fault of up to 10kA but the data did not seem to indicate any fault current limiting capability.


Quote:

Originally Posted by Stubbie (Post 68599)
Handyman.....

Kangaroo

I'm not able to find a characteristics on the HRC fuse you speak of so is this a fuse class that is current limiting and inductive load rated?

Yes. All HRC (High Rupturing Capacity) & DIN fuses have current limiting abilities.

Our plug fuses will limit the current to 1/2 cycle before opening for short circuit protection.

As previously mentioned, I couldn't find any data that supported current limiting abilities for the OPs fuses (S & T series dual element time delay).

I don't profess to be a fuse expert so can only tell what I "think" I'm sure of.

Some reference material

T_CWD_Fuses.pdf (application/pdf Object)

http://www.bussmann.com/library/bifs/8005.PDF

Thanks for the info Stubbie...made for some interesting reading:yes:.
I only have one question. Since these "standard" type wire/link fuses have an interrupt capacity of 10kA, does this mean that the residential supply has a prospective fault current not exceeding 10kA?

In Australia, residential distribution transformers are usually larger than 150kVA. This means that the prospective fault current at the transformer is somewhat larger than 6kA. Generally, energy authorities are able to supply prospective fault current information for any given location, which is usually a minimum of about 25kA for all urban areas. Consequently, all Australian residences are protected by a BS88 (older installations) or a BS1361 fuse, which limits the fault current to less than 10kA (BS88) & less than 4-5kA (BS1361). Both fuses have an interrupt capacity of greater than 100kA. Most electricians now are told to use the BS1361 fuses. As a result, residential circuit breakers can be a minimum size of 6kA (BS1361) & 10kA (BS88). Basically, the BS1361 fuse is now standardised for domestic use & hardly ever blows. Their main purpose is to limit the fault current.


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