New Range/Oven - going from 3 to 4 prong outlet

[Boilers]

We are getting a new electric oven/range next week to replace our current electric one. We currently have a three prong outlet and, in the interest of safety, I figured I would check to see if it could be converted to a 4 prong. The current stove was put in when we bought the house 17 years ago. The picture shows what I found.

It looks like I have two hots and a ground coming in over 8 gauge braided wire from a 40 amp breaker. The ground is not copper though. Then there is a separate 12 awg with only the neutral being used. The good news is that I have a separate ground wire. But, 1) I'm not sure about the condition of the braided wires - they look more work than I typically see; 2) is it ok to use a separate 12 gauge neutral; and 3) is it ok that the ground is not copper?

Can I salvage this or do I need to have an electrician run a new line?

 

[Stuff]

Connecting the braided ground and white neutral isn't good. Lots not right with that black cable. Do you know where it goes? Ends of black wire and copper ground look like they were previously attached. Not at all legal but maybe it was used for a 120v receptacle elsewhere?

With the cabling you have it is not code to install a 4 prong outlet. Legal is 3 prong with the old wires. I would remove the white wire / black cable and put the receptacle back. The new range can have a 3 prong plug attached. Almost all you select 3 or 4 prong when you buy it and they have instructions on how to attach either to the range.

 

[Sponsor]

 

[Boilers]

Thanks for the response Stuff. You're right that it looks like the "new" cable/wires have been used before, but I'm not sure where they come from. The new black wire is not live, so I assume this was done at some point after the house was built to connect neutral. Are you saying I can get by with the old wire and just take off the new white wire (keep only the ground wire there)? What about neutral then? Is that needed to run some of the 120v electronics (clock, etc.)?

 

[Stuff]

Yes, remove the white wire. Do check in the electrical panel to verify that the braided wire is connected to the ground/neutral bus.

These old three wire 240 volt receptacles use the same shared wire for both neutral and ground. Neutral for the 120v loads and ground for safety. That was allowed for many years and should be grandfathered in for what you have. New installations or modifications require four prong receptacles with four wires.

When you use a three wire plug and cord on a range or dryer there is a jumper installed at the connection point which combines the neutral and ground.

 

[Mr. Mint]

More than likely, the braided bare wire is the neutral return for the 220 volt wiring scheme. Why the white 12 gauge wire from another cable connects to this point is very unusual. Neutral returns and bare ground wires should be kept separated until they reach the circuit breaker panel.

 

[WorthFlorida]

Two concerns. There is electrical tape at one of the 120v lines and what is the dark spot on the lower wire? Is the fabric pulled away from the insulation (no bare copper)? If this on a first floor and a basement where the panel is I would run a new wire altogether. If it is not possible, it looks like there is enough slack to cut back the wires without frayed insulation. Definitely remove that black cable.