Electrical Questions? Ask an Electrician Online.
Hello .. here is the basic idea
the ground/neutral bar in the main panel is where the grounding electrode conductor is connected
that wire goes outside to twm driven groung rods
when running wire to a sub panel ... there must be a neutral wire and a separate ground wire ,, both connected to the ground/neutral bar in the main panel
but separated in the sub panel
If there is no ground bar in the sub panel , then one should be added
I included picture to show service into disconnect.
There is no ground bar. There is no ground going to earth.
This has been this way for over fifty years.
I am installing a breaker panel to replace a fuse panel.
Should I run a ground from the neutral bar in this disconnect to the new panel
that I am installing. even though it has not had one for fifty years.
If this is the first panel after the meter socket .. then this should be upgraded a bit
there should be a gronding wire going to two driven ground rods
Or .. should I leave this the way it is and just run a ground to earth from the ground bar in the new panel. Seems like that is what I should do. If I do need to run a ground from this disconnect to the new panel, does it connect to the neutral bar here? then go to the ground bar in the new panel. It looks like that would bond the neutral to the ground in the new panel. Which is not suppose to happen in sub panel. The new panel would be a sub panel, right?
that wire will be terminated in a lug attached to the panel box
wHAT IS THE NEXT STEP FROM THIS BOX .. YOUR NEW PANEL ?
What size fuses are in this old panel?
I don't know , but can go look
which panel are you talking about
the old panel I am taking out
the one you showed me
are you taking it out ?
Wait a sec
and looks like there is one more cable out of this disconnect ?
Sorry about that cut power when I pulled disconnect
there be a 200 amp fuse on each side... that would be two of them
there is only 3 wires coming from service and 3 wires going to old panel
there is a central heat and air disconnect added to the side of this panel
that is the other cable you see
are you thinking or did I lose you
You still there?
oK .. and is there another fused disconnect at the AC installation?
just a breaker
OK .. wow that wire does not look big enough for 200 amp fuses .. can you read the printing on the jacket ..
What do you mean jacket...sorry
anyway .. this is the first disconnect .. and therefore needs to have the ground rods connected here
two ground rods 6 feet apart , driven 8 feet into the ground near the disconnect
to that neutral bar.. right
the oouter covering of the cable .. either one will do .. from the meter or to the old panel
you lost me
the cable s in and out of this picturted disconnect .. there is printing on the outside covering ..
that tells what size wires are in it
like AWG 6
let me look
That cable must be older than you... there is no writting on the outside of the cable coming in or going out of this box ... I went to meter and there is no writing there either
I can see the stamp on the cable to the AC .. so was hoping for the other
there is writing on that one... you need to know that?
does the old panel have a main .. is it 100 amp ? or ?
ya what is that wire size .. just for comparison
yep ... don't think it says..but will check
and the new panel is 100 amp .. ??
Style U type RH 8AL
new panel is 200 amp
old panel does not say 100 or 200 amp
OK .. to make all this legal , you need the ground rods .. and a 4 wire cable to the new panel .. 200 amp panel needs 2/0 copper or 4/0 aluminum wire
I don't think they did things same 50 years ago
I do think that your service is not 200 amp .. but you can check with the power company on that .
if not then you will also need to upgrade the service drop, meter socket , and service entrance conductors to that first fuse box
and there have been 50 years for someone to mess with it
which is what usually has happened
can I not use a 299 amp panel?
you can use the 200 amp panel .. even on a 100 amp service ..
that is good
but the wire size need to be verified for ampacity rating to make sure that it is protected by the correct size fuse or breaker
what you have described tyo me does not seem right
I need to connect size 2 wire from neutral in disconnect to ground on new panel?
what does not seem correct?
A #2 wire aluminum , is about the size of your little finger .. a 2/0 wire is very much larger .. and 4/0 aluminum is getting close to a 1/2 inch pipe size
#2 aluminum wire is good for 100 amp service
this looks like #2 wire ..
I bought a 25 foot num 6 copper wire for ground
so the 200 amp fuses do not sseem right to me
can I not use that?
that is good for the ground
are you saying it should have smaller fuses
between the panels and to the ground rods
how far is it tfrom the fused disconect to the sub panel
less than a foot
then if you are ghoing to re-do this I would suggest removing the fused box and running from the meter socket into the new panel ..
eliminating one stop
But would have to rewire whole house
still need the ground rods .. but this old fuse thing is not needed ..
because wiring would not reach where the old disconnect is
is there is not benough slack to get your AC wire into a new p[anel .. you can use a junction box and extend it
how would I get the service to reach new position?
how far is it to the meter socket .. before I get my foot firmly stuck in my mouth .. please
about 1 foot
all pretty close
OK .. I am going on the thought that this service is not 200 amps rated
the meter socket is close enough that it would be less expenxive to run a new wire from the meter socket to the new panel .. locate the panel where all the circuit wire will reach .. and extend the AC cable thru a junction box to get it to the panel ..
that is how I would do it
.. NOW if you have other thoughts .. or wish to go on as you started .. I will help yopu with that
the other option would be......
does the ground wire to the new panel connect to the neutral bar in the disconnectwire
I am still thinking that your existing wirtes are only rated for 100 amp at the most .. and that the 200 amp fuses are too big to protect the wire
ok I will lower to 100 amp
if I can still find them
is the first disconnect .. the wire from the ground rods connects to same bar or lug as the service ground/neutral
tell me how to connect the grounds
got that one
if the wire from the meter is about the size of your little finger .. rather than like a hot dog .. then it is probably #2 aluminum .. good for 100 amps
the wire from meter is stranded
in the sub pANEL THE neutral bar is isolated fron the panel box.. and a new ground bar is added to the back of that panel box ..
size of a finger .. or a hot dog ?
it already has one
there is 2 ground bars in new panel...one big one small
if this new panel is to be used as a sub panel there can be no connection between the two bars
big on left side small one on right
I understand that
there may be a strap between them .. needs to be removed
no strap and not using screw
OK .. I cannot see what you can ... so may overstate things to be sure that we are on tyhe same page
the ground from the disconnect to the new panel ... ties in where on the disconnect
attach a new lug to the box .. similar to the one that is there .. and put the wire for the ground rods and the ground wire to the new panel in it
the body of the box is good for a connection between the lugs
is this new lug connected to the actual box metal...bonded
This ground wire is bare. does it matter if it touches either box on exit and entrance?
yes .. tek screw it to the box ... or you can replace the one that is there with a 4 position lug
does not mater if it touches thee box .. all metal is same ground potential
if I put in 100 amp fuses and I have a problem with blowing ... will it be alright to go back to 200 amp?
since they have been in there a long time
I cannot verify the wire size with the info you have given me .. looks like 100 amp wire to me .. but that is a guess ..
I cannot tell you it is OK to put 200 amp fuses in the box .. because of my thoughjts of the wire size
You have helped alot. how can I give you extra?
you can use the 200 amp panel .. IF you have it going thryu the fuse box with replacement 100 amp fguses in it
rthen if youi sometime upgrade the service drop .. your panel will be good for the 200 amp new service
the 100 amp fuses in the disconnect will protect all the 1oo amp wire and will over ride3 the 200 amp main in the new panel