TheGreyGoose
Member
- Joined
- Jan 27, 2017
- Messages
- 10
Hello gents, I've checked around in the electrical / lighting threads and just can't find exactly what I need. If anyone can give me a steer to any sister threads I will delete this but I may have some hurdles not mentioned in other threads so I felt this worthy of a post.
I need to run a new high amp circuit for my large air compressor, a late 80's or 90's Saylor-Beall 705 with a Doerr 5hp motor. The motor badge says single phase 230v / 29 amp (F type..whatever that means). Luckily I have two final slots left open on my home's main service panel (200 amp) which is located on the exterior of the house on the back of my garage.
I'm placing the compressor on a concrete patio slab right behind the garage up against the house so the wire travel / length will require 35ft at most. I'm thinking I will want to run most of it from the panel, then inside the garage along the back wall, then back out and over ~6ft to the closet enclosure that the compressor will live in.
I already have a dedicated 30 amp breaker for my Harbor Freak CE-170 welder which I installed last year and and if it was within code I'd thought of just adding onto the last of two receptacles I had ran for it but quickly realized I don't want to trip the breaker if I'm welding and the air-comp kicks on too. I could of course shut off the compressor during this time but in time that may prove to be a nuisance so I figure I need them on separate breakers and I'm guessing that the air-compressor may need more power being 5hp.
Currently the 3 wires coming from the compressor are sheathed in ~10ft of flex conduit from where it was previously hard wired in the shop of the previous owner. I figured I would keep it the same way and wire it to the new receptacle box or a service disconnect with a lever and would install that box in the closet. I also wanted to know if I could mount a plug on the end. I'm pretty sure I couldn't even use a plug with flex conduit without need of swapping over to some SJOOW cable or the like or that it's against code to do so. And even if ok I probably should not use any plugs since it will be basically be an outdoor mated connection.
So.. I'm sorry this is so lengthy. My main questions are:
#1 -- What size breaker should I use for a 230v / 29amp motor? 30amp, 35amp, or 40 amp? I assume any of those three can use #10 gauge THHN orange type Romex or do I need to run 10 gauge flex conduit inside the garage wall (and will actually run it through ceiling joists near other runs). *I did find a good archived thread on the WeldingWeb forum with a similar project and his spec's are very similar but his motor was 21.5 amp. So do I need a larger breaker, bigger wire, etc for a 29 amp motor? ( Here's that thread for reference .. http://weldingweb.com/archive/index.php/t-34599.html )
#2 -- I also want to wire in a shut-off box inside the garage right before the receptacle box so that if ever needed for things such as going on vacation for or any extended months of non-use, I can just shut off power to the receptacle box there rather than having to go outside, open the main panel, and shut off the breaker.
Is this ok to do and what kind/type of shut off box would be recommended?
#3 -- If I'm going to hard wire the two connections inside the receptacle box rather than use an outlet and plug what type of connectors should I use to mate the wires? I assume large wire nuts is not the proper way to do this. I mean it may be ok, but should I use the bolt / crimp type and electrical tape instead?
And lastly,
#4 -- Since the tool connection point will be on the house exterior and has flex conduit (~1" diameter) from the tool what type of face-plate or box should I be looking for? I assume it needs to be moisture rated since this is outdoors. I also recall in the past that for whatever reason some codes require that if you use flex conduit or pipe on one end of a fixture or tool, that you are supposed to use the same all the way to the service panel. If that's the case then should I ditch the idea of Romex inside and conduit outside? Thoughts?
#5 -- Lastly, in the thread I linked above in #1 the last poster "Cotton" also recommends use of a motor starter with a thermal overload relay. Is that the big box on the side of my compressor that already exists, or is this something additional to add on in between the receptacle box and the line into the main power box on the compressor itself? Excuse all my nooby-ness but while I have wired a few houses before and have done a lot of other electrical work I'm really new to wiring in big shop tools.
#6 -- If it wasn't obvious I'm trying to avoid paying an electrician $500 to do this for me lol. It's just one new circuit.
I need to run a new high amp circuit for my large air compressor, a late 80's or 90's Saylor-Beall 705 with a Doerr 5hp motor. The motor badge says single phase 230v / 29 amp (F type..whatever that means). Luckily I have two final slots left open on my home's main service panel (200 amp) which is located on the exterior of the house on the back of my garage.
I'm placing the compressor on a concrete patio slab right behind the garage up against the house so the wire travel / length will require 35ft at most. I'm thinking I will want to run most of it from the panel, then inside the garage along the back wall, then back out and over ~6ft to the closet enclosure that the compressor will live in.
I already have a dedicated 30 amp breaker for my Harbor Freak CE-170 welder which I installed last year and and if it was within code I'd thought of just adding onto the last of two receptacles I had ran for it but quickly realized I don't want to trip the breaker if I'm welding and the air-comp kicks on too. I could of course shut off the compressor during this time but in time that may prove to be a nuisance so I figure I need them on separate breakers and I'm guessing that the air-compressor may need more power being 5hp.
Currently the 3 wires coming from the compressor are sheathed in ~10ft of flex conduit from where it was previously hard wired in the shop of the previous owner. I figured I would keep it the same way and wire it to the new receptacle box or a service disconnect with a lever and would install that box in the closet. I also wanted to know if I could mount a plug on the end. I'm pretty sure I couldn't even use a plug with flex conduit without need of swapping over to some SJOOW cable or the like or that it's against code to do so. And even if ok I probably should not use any plugs since it will be basically be an outdoor mated connection.
So.. I'm sorry this is so lengthy. My main questions are:
#1 -- What size breaker should I use for a 230v / 29amp motor? 30amp, 35amp, or 40 amp? I assume any of those three can use #10 gauge THHN orange type Romex or do I need to run 10 gauge flex conduit inside the garage wall (and will actually run it through ceiling joists near other runs). *I did find a good archived thread on the WeldingWeb forum with a similar project and his spec's are very similar but his motor was 21.5 amp. So do I need a larger breaker, bigger wire, etc for a 29 amp motor? ( Here's that thread for reference .. http://weldingweb.com/archive/index.php/t-34599.html )
#2 -- I also want to wire in a shut-off box inside the garage right before the receptacle box so that if ever needed for things such as going on vacation for or any extended months of non-use, I can just shut off power to the receptacle box there rather than having to go outside, open the main panel, and shut off the breaker.
Is this ok to do and what kind/type of shut off box would be recommended?
#3 -- If I'm going to hard wire the two connections inside the receptacle box rather than use an outlet and plug what type of connectors should I use to mate the wires? I assume large wire nuts is not the proper way to do this. I mean it may be ok, but should I use the bolt / crimp type and electrical tape instead?
And lastly,
#4 -- Since the tool connection point will be on the house exterior and has flex conduit (~1" diameter) from the tool what type of face-plate or box should I be looking for? I assume it needs to be moisture rated since this is outdoors. I also recall in the past that for whatever reason some codes require that if you use flex conduit or pipe on one end of a fixture or tool, that you are supposed to use the same all the way to the service panel. If that's the case then should I ditch the idea of Romex inside and conduit outside? Thoughts?
#5 -- Lastly, in the thread I linked above in #1 the last poster "Cotton" also recommends use of a motor starter with a thermal overload relay. Is that the big box on the side of my compressor that already exists, or is this something additional to add on in between the receptacle box and the line into the main power box on the compressor itself? Excuse all my nooby-ness but while I have wired a few houses before and have done a lot of other electrical work I'm really new to wiring in big shop tools.
#6 -- If it wasn't obvious I'm trying to avoid paying an electrician $500 to do this for me lol. It's just one new circuit.
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