arlettde it is (a) 4 separate connectors on the device itself? or is it (b) fourth pin on one plug? everyone has a differant Senario. In the case of (a) you will probably need a new circuit breaker feeds fetched from your board. Not too expensive in this case. If it (b) you will probably need a different "phase" or brought into line with your service provider unless you've seen some heavy appliances like A/C units. That will be very expensive. Find out whether your device (method b) single phase (method a) or 3-phase or out of manualand, which should give you an idea
thoughtlessly something you were not sure, you can even hook up in your house without a significant change? WTF?
What you should have done was to determine the existing stove power, and then find the new unit, to run the bear, at least on what the existing offer is. There are at last count two different plug configurations for what I can only assume, is 240/50 amp service. You can even get through a dryer cord ....
No matter what, you need someone that what they are doing out there knows how this is enough voltage to kill you if you go monkeying with it.
The addition is the 4 th wire, you have lighs in this case. The three wire has a ground and two hot wires. Read with the upgrade in electronics, the use of a nuetral lighting and digital outs for the required units of common use. A safe and cost effective manner requires a little luck. If the ground wire that is in the container the same size as the hots it can end in a nuetral bus pass and an open grond wire can be easily installed. It is a 50Amp circuit requires #8 August by wire code and I like the three neutral wires in your area f rec is No. 8 and the third wire is not bare or minutes as part of the outer cover braded cable then. Size of the soil can be No. 10.
More than likely, the multi conducror cable feed is not rec area over the pipeline and the lines then drill a small hole through the bottom of a single story access with underground power. find the grounding of the meter panel binding one determine a good way to get from the ground rod or cold water pipe, run around the field. This four wire, go get a new plug and good luck Answering questions in Maintenance and Repair White riding mower ... an LT-12 LT-deck fit on a 145? Sand has the floor plan to help drive home foundation? Vents in the ceiling blowing dust? My microwave started sparking?