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The property I've been renovating has two separate meters. One on the house and one on a detached garage that used to be an automotive shop. I recently upgraded the house to a 200amp service (has exterior disconnect and 4 slots available outside) and I want to disconnect the garage meter and connect it as a subpanel. Solely because the garage electric bill runs more than the house due to the second service cost. The garage panel is properly grounded with rods and I'll be running SER 4 strand cable from the main to the sub. I'll be unbonding the ground and neutral in the garage once it's a subpanel. Adding drip loops and anchors at each connection point. My question is best practice on running the cable. It'll be about an 80-95ft run and underground is not an option without cutting out a lot of concrete. The service line to the garage is overhead with three strands going into the weatherhead (hot, hot, neutral). I'd have to fish a ground in/out to connect to the 4 strand SER coming from the house. The house is rectangle with the panel on the SW corner and the garage located off the NE corner. I.e., the garage is on the opposite side of the main panel of the house.

My question is it's equally easy to run through the attic vs. the exterior/perimeter of the house. In the attic I can save some wire by running the diagonal, house exterior I'd have to follow both sides. If I run through the attic I can either exit through the roof or gable on the side nearest the garage weatherhead. Is there a benefit to either? If I exit the roof, do I need a weatherhead in the sense that I "splice" the cables? Meaning I run the SER in the conduit individually, then I splice from the garage weatherhead to this new weathehead (about 25ft overhead). OR do I keep the SER cable fully intact coming out of the weathehead and then splice at the garage weatherhead? What's the best practice for running about 25ft of SER overhead is basically what I'm asking. Spliced for the gap or unspliced, 2-2-2-4 Aluminum.

Other options?

Thank youenter image description here

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If you have 3 insulated conductors and the messenger (support cable is aluminum) the messenger is normally the ground.

Since you have a breaker inside the house you can enter the house and go through the attic. This may be both easier and a shorter run.

Make sure you are clear of any window openings I think it is 3’ from them. You are well above code requirements for height so you are good there.

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  • Thank you for your response Ed. What are your thoughts about exiting the house? Roof or Gable end? Do I run an uncut cable out of the penetration/weatherhead or do I splice at the house and garage? I.e. do I run an 85ft line straight the garage weatherhead or a 60ft to the penetration then splice 25ft between the two weatherheads.
    – Ethan
    Mar 24 at 17:38
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    Definitely gable end on both buildings would be the way I would do this. Have the messenger Cary the weight and a drip loop feeding to the weather head in your case not knowing about windows it may be easier to have the messenger below both weatherheads then no loop is needed. Depending on the type of weather head you can go either route I prefer no splices but when you have a long run it is much easier to add Polaris splices. Over the years I have moved to Polaris type cost more but if you need to change anything it’s easy and I have not hade them fail I have had crimps and al wire fail.
    – Ed Beal
    Mar 24 at 18:42
  • Awesome. Thank you again for the help Ed. I appreciate it!
    – Ethan
    Mar 25 at 18:26

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