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Discussion Starter #1
I have an older house with all two prong receptacles and no ground wire. Since the neutral line is connected to the ground bar in the breaker box, is it okay to connect a wire on a three prong receptacle from the ground screw to neutral side of receptacle in order to have a grounded receptacle?
 

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No, it's not OK.

Just imagine what might happen if there was a problem with that neutral somewhere along it's path? If you had, for example, your washing machine plugged into that outlet you've now energized the chassis.

It's unsafe and against Code.
 

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NO It is very unsafe to do that. If the neutral ever became disconnected then the metal frame of your devices would be live and a shock hazard.

You can replace them with GFCI and leave the ground off. They will not be grounded but will allow a three prong plug to used.
You can pull a ground wire from the panel and add it to each receptacle. However if you pull a ground wire why not pull a new cable.
 

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UAW SKILLED TRADES
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Well now you know not to do it. There are lots of people who think because of the common connection with the utility grounded conductor aka service neutral at the neutral bar in your service panel that they assume it must be ok to connect neutral and ground elsewhere.

Problem is the grounded conductors .. ie...white wires...neutrals .. are the current carrying wires for the circuit to be completed with the transformer. They are not the same as equipment ground wires that can be used for grounding receptacles. These ground wires are used to complete the circuit to carry ground fault current back to the service panel, then out the service neutral to the transformer. This allows current to flow through the protecting circuit breaker by completing the circuit just like the white neutral wire. Only this current will be 100's of amps because there is no load to restrict the amount of current used by the circuit. It's basically just a loop of wire starting at the transformer and coming back to the transformer. That huge current flow must pass through the circuit breaker causing it to trip and de-energize the circuit. Then the ground fault can be located, corrected and the circuit can be turned back on.

The point is white wires aka grounded conductors carry the system current in a branch circuit anytime you are operating a load like a light bulb or dishwasher or iron etc...

Equipment ground wires only carry current when a fault occurs. If we connect to the neutral from the ground screw on a receptacle we just gave that neutral current a path to go somewhere else. So imagine you plug into a receptacle where you have connected neutral to the green ground screw of the receptacle ... which is in turn connected to the ground pin of that receptacle. When you plug in your kitchen aid mixer with metal housing you have just given the neutral current a path to travel up the ground wire in the power cord to your mixer .. energizing the metal .. if the neutral in the branch circuit would come apart or lose connection.
So the proper way to install 3 prong grounding type receptacles on ungrounded wiring is to use gfci receptacles. However even though this protects you from electrocution it does not give you a ground. The only way to get a safety ground or equipment ground is to install new wiring. If your just wanting to be able to plug in a 3 prong appliance then go the gfci route.
 
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Thank you for your answers. I didn't think this was going to work since I had never heard of doing it. I figured there must be a reason for it but had to ask. I'll have to go with the gfci outlets.
 

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Thank you for your answers. I didn't think this was going to work since I had never heard of doing it. I figured there must be a reason for it but had to ask. I'll have to go with the gfci outlets.
Yep that works. When you hear the term 'bootleg ground' that means a neutral to ground connection has been made at a receptacle.

Just so you will know thousands of homes have bootleg grounds on electric ranges and dryers. These are the ones where you have 3 prong non grounding receptacles. So if you have this and it is not too much of a problem it would be an improvement in safety to install 4 wire branch circuits and 4 wire grounding type receptacles and replace the 3 wire ones. Once you do this you remove the bootleg ground to the frame of the appliance, change the power cord to 4 wire and your good to go.
 

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The only reason it was allowed on dryers and ranges was there was only one device on the circuit.
 

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The only reason it was allowed on dryers and ranges was there was only one device on the circuit.
I didn't know that Joe thanks for the History lesson ...:thumbsup:
 

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The only reason it was allowed on dryers and ranges was there was only one device on the circuit.
And we all know why this exception was removed. We've all heard stories of folks getting shocked when touching a range or dryer.
 
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