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Hi, would be glad to assist.
It sounds like you have a home wired more recently than the information you have on hand. It used to be commonplace to have the neutrals and grounds on the same neutral bar (depending on the year the house was built). Today, homes are wired with a 4 wire system. 2 hot legs (240 volts), a neutral and a completely separate ground. The grounds and neutrals have 2 separate bars now. So, yours has a neutral bar for ONLY the neutrals and a ground bar for ONLY the grounds. Be sure that on the neutrals, only 1 wire per screw, where as the grounds can have more than 1 per screw.
My house doese not have a separate bar for ground. the two unshielded wires are going to two different screws that appear to be holding the housing in place. I guess my question is: is it safe to put the gd wire on the the neutral bus. I have heard that the neutral bus is just floating and might not provide good protection against shock?
2 unshielded wires,? From where?
So you have only ONE bar to the side? All the whits and bare grounds are attached to it?
Are you saying you have a cable in the panel, that has the bare wire attached to a screw that is holding the panel to the studs. And all the rest are connected to the neutral bar?
I'm sorry. I did not mean unsheilded but bare wires, ground wires are attached to screws not on a bus bar but screws that are just screwed into the panel housing. There is only one bar and only white wires are attached to it.
Is there any way to take a picture and post using the paper clip icon above?
No I can't. I can tell you this is an old house and looks like the circuit panel was not done too professionally. My concern is: In housing where you only have one bar for neutral and ground should that bar be going to earth ground? this neutral bar has no external connections.
I understand. I just wanted to see what the screws looked like to be sure of what was happening.
If you have 1 bar, the ground and neutral share the bar. The whites should be under only 1 screw each and ground can be more than one. There should be jumper from the neutral bar to the housing.
Normally that jumper is silver in color from the factory
Also, there should be a large copper bare wire that connects to the METAL water piping or to an outside ground rod.
Your main service cable has only 2 blacks and 1 stranded uninsulated wire? Total 3 in service main, correct?
I don't have a jumper going from the bus bar to the housing. The two wires going to service main are red and the third wire has been spliced into another wire coming from bottom of the panel through a metal pipe. I have no idea if this is going to a ground rod or not. There is a reading of 47 volts ac between the bus with white wires to the panel.
Are all the wires in the panel in conduit? Pipe?
No all the wires are not going through conduit. The wire that is spliced to the wire coming from the bottom of panel through the metal pipe is going to the the bus with the white wires.
The spliced wire goes from the neutral bar to the splice at the bottom of the panel and nowhere else, correct?
That is correct.
I really wish I could see it, it is very odd situation. There is no way to get a picture of the panel and setup?
I will try. Do you have an email to send picture to?
Email is not allowed. The little paper clip icon on the bar above is to post pictures right into our chat
I can't get picture attached. All I need to know is that spliced in wire going to the bus bar going to an outside ground. And if I ground the bus bar to the panel should everything be ok?
I am just trying to find a safe ground point to install this hot water heater is it the panel housing or the bar bus with white wires.
The spliced wire , if it is the only large wire on the neutral, should go to the meter. Yes, but I have concerns on that splice? Normally 1 cable with 3 wires comes to the panel and not 2 from one location and the third from another.
the 1 cable with three wires is coming into the panel from the same place. two red and one white. the white wire however goes to the bus bar and is also spliced into that wire thats coming from bottom of panel. When you say "if it is the only large wire on the neutral,should go to the meter."
Is that white wire going to meter ground?
Ok, there was mis-understanding somewhere.
Sorry for any confusion, I thought you said only 2 wires from main service
Ok, the one going out of the bottom most likely connects to water pipes or rod for the main ground junction.
Your service is right with the 3 wires, it is a 3 wire system
Ground sounds correct, you would have look somewhere that it may connect to a water pipe or goes outside to a ground rod driven in the ground. I lean towards water pipe.
In that case then the neutral bus with all the white wires are grounded so the ground wires and neutral wire will be safe to go to that bus. Is that correct?
Correct, they all go the that bar. It is one for both
And the panel should still be strapped to the neutral buss correct.
YES, should be small strap to panel housing with screw
What problem could it cause if panel is not strapped to neutral buss? Right now there is 47 volts reading between the two points.
Can I just run a wire from the buss to panel housing? There is no strap connected to the buss.
Proper Neutral-to-Ground Connection
When a neutral-to-ground connection is properly made in accordance with the NEC, the voltage between any metal part of the electrical system to the earth will be zero volts.
The National Electrical Code requires a neutral-to-ground connection to be made at service equipment only and there shall not be any neutral-to-ground connection on the load side of service equipment
Try your Home Depot or Lowes and see if they sell them separarately.
Lets verify again. ALL of the ground wires connect to the Panel case? And ALL of the neutrals (white) connect to the neutral bar? AND you only have a 3 wire feed in the service cable? Yes or no to each. YES,YES,YES?
Yes to all three but there are only two ground wires.
Old cables with only 2 wires? Someone added the 2 new cables?
One of the cables has two wires. One white and one bare. the white is going to the buss and the bare is going to the panel. The other wire appears to be fairly new for the dryer.. it is four wires. black and red going to two different fuses, the white going to the neutral buss and the bare attached to the panel with a screw.
I said two different fuses. I meant ckt breakers.
You need to look at the one where someone has cut the black out of the cable. One white and 1 bare is NOT right.
I have no idea why it is there. It can't be doing anything because it is not going to a ckt breaker.
They could be using it because they lost neutral somewhere and instead of doing proper, they did something wrong. It may benefit you to have local electrical company for an inspection. There are some issues here, that will be very difficult to work through in a communitive reasonable time
Ok But my confusion now is it ok for the neutral bus to be grounded or not?
Remember neutral carries current also, must be careful trying to disconnect one with power.
By NEC it is supposed to be at the panel.
You may need to trace out that one cable to see where it is going. It could be creating your voltage
I was telling you earlier that there was white wire coming from the meter that was going to the neutral bus and also spliced into another wire that you felt was probably going to ground rod or water pipe. Is this part still ok?
I cannot see it, you stated that the main neutral is coming in with the service cable. Then a wire is spliced onto the neutral and going out the botoom of the panel. Correct?
Is it a large wire?
That is correct and it is a large wire.
It is hard to say without seeing the cable. Large is speculative to me. Normal ground to pies and rods is #6 or so, thats about 3/16 to 1/4" diameter
This wire is considerably bigger than a # XXXXX so it probably is # XXXXX My question is if this is going to the pipe then is the connection to the neutral buss valid as you said earlier? I can get a jumper to strap the neutral buss to the panel. I didn't know the neutral buss could still carry electricity if it was connected to ground.
Yes, it is correct, the ground to a water pipe or rod, will connect to the neutral buss on a 3 wire system as you have.
The neutral wires (white) themselves carry current. Not because they are connected to ground.
If you disconnect any white wire under load it will ARC..
That is why on the other end from the panel (panel is different) the grounds and neutrals do not connect to each other. Only at the panel.
Ok. In the newer systems where they have separate buss for ground and neutral is the neutral bus still connected to ground or is it just floating?
It connects to the panel case only
Only at the panel. Any subpanel etc. have complete seperation of the bars
But in my system if I connect the panel to neutral buss there is no problem even though the buss is going ground. Is that correct.
Neutral buss MUST connect to the panel case
What happens if it is not like in my house?
Yours is no different at the panel. It changes elsewhere in a 4 wire panel
What problems could there be if the panel case is not connected to neutral buss?
One, it is a safety issue. Shock hazard. Your case could become powered. Ground keeps everything from becoming powered.