Ideal wiring situation


Results 1 to 11 of 11

Thread: Ideal wiring situation

  1. #1
    Member gr-cnc's Avatar
    Join Date
    Dec 2018
    Location
    grand rapids
    Posts
    23
    Downloads
    0
    Uploads
    0

    Default Ideal wiring situation

    I've decided to run a dedicated 220v circuit out to my shop for my router. I have a 2.2kw 220v spindle and a 48V 20A 1000w switching PS for 4 7A steppers. I also have a 24v PS for the BOB. One way to do it is run four wires (B R W G) into the box and split the circuit to power both 220v and 110v components. But to save the expense of a 4th wire (it's about 65' from main panel to shop) I thought instead to just have a separate power cord for 110v that plugs into an outlet.

    Will that create a ground loop?

    Or would it be better to run a clean 3 wire supply and then use a 48/24 stepdown transformer to power the BOB? Those are roughly the same price as the extra wire, but it would be less messy in the control box. As I write this, now I think that's the right way to go. Unless someone advises against it. Thoughts?

    And to double check, is 8 gauge wire and 40A breaker good?

    Similar Threads:


  2. #2
    Member Jim Dawson's Avatar
    Join Date
    Dec 2013
    Posts
    4042
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    I have done it successfully all 3 ways that you suggest. For industrial applications I normally use a transformer (240/120V) in the panel to supply computer power and power up small power supplies.

    You mention ''step down transformer'' , that implies AC output and would not be acceptable for the 24/48VDC supply. I think what you really mean is power supply. Also, most power supplies today are universal, including computer power supplies, they will run on about 100 - 240 VAC. Some have automatic input voltage detection, some require flipping a switch, and others require wiring to the proper terminals for the input voltage.

    On my lathe and mill, I power the VFD from the breaker panel directly, and plug in the controls to a 120V outlet on the wall.

    On the other side of the shop I ran 4 wires to another machine and split the power in the cabinet.

    A 40 amp breaker is acceptable for a #8 wire.

    Jim Dawson
    Sandy, Oregon, USA


  3. #3
    Member
    Join Date
    Jan 2005
    Location
    USA
    Posts
    10764
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Quote Originally Posted by gr-cnc View Post
    I've decided to run a dedicated 220v circuit out to my shop for my router. I have a 2.2kw 220v spindle and a 48V 20A 1000w switching PS for 4 7A steppers. I also have a 24v PS for the BOB. One way to do it is run four wires (B R W G) into the box and split the circuit to power both 220v and 110v components. But to save the expense of a 4th wire (it's about 65' from main panel to shop) I thought instead to just have a separate power cord for 110v that plugs into an outlet.

    Will that create a ground loop?

    Or would it be better to run a clean 3 wire supply and then use a 48/24 stepdown transformer to power the BOB? Those are roughly the same price as the extra wire, but it would be less messy in the control box. As I write this, now I think that's the right way to go. Unless someone advises against it. Thoughts?

    And to double check, is 8 gauge wire and 40A breaker good?
    Run the 4 wire this is something you don't want to try and cut costs on your 4 wire you can have your 240v and 120v from the one source which it the way it should be done

    The separate power cord can cause you EMI problems and also a possible Ground loop depending on how the Grounding is done of the ( 2 ) supplies so not such a good idea

    A transformer is doable and most likely will cost the same or close as the 4th wire, so still the 4 wire install has more options and a better choice

    Mactec54


  4. #4
    Member machinehop5's Avatar
    Join Date
    Aug 2009
    Location
    United States
    Posts
    343
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Five wire are used to supply sub panels is code I think three phase?


    anymorequestions or comeback ...call my lawyers. lol
    merry mary all..happy 2020

    Last edited by machinehop5; 12-24-2019 at 09:42 PM. Reason: img


  5. #5
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    Shelby Township
    Posts
    34697
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Most power supplies have the option of running from either 120V or 240V.

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


  6. #6
    Member Muzzer's Avatar
    Join Date
    Apr 2014
    Location
    UK
    Posts
    46
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    In N America, the "220V" supply is simply two 110V outlets that are 180 degrees out of phase, so you can achieve what you want with 3 wires - one 120V, the neutral connection and the other 120V. You get your 240V across the 2 phases and the 110V between either phase and neutral. The neutral is grounded at the utility transformer and is common to both phases, so the issue of a ground loop shouldn't arise. This is how I ran my European machine tools when I lived in Canada.

    If you look at the wiring of a modern kitchen in US / Canada, according to code there should be a "split" receptacle with both phases present in it. That's so you can run a kettle and another high current load (eg toaster) from the same dual receptacle (on different phaess) without tripping the 15A breaker. For Brits living in N America, that allows you to replace the std dual receptacle with a 240V receptacle so you can run a "proper" (3kW) kettle - tea drinking is a serious business for us!



  7. #7
    Member
    Join Date
    Jan 2005
    Location
    USA
    Posts
    10764
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Quote Originally Posted by machinehop5 View Post
    Five wire are used to supply sub panels is code I think three phase?


    anymorequestions or comeback ...call my lawyers. lol
    merry mary all..happy 2020
    They are not using 3 Phase Single Phase is only 4 wires if you want 240v /120v from the same supply if you only want 240v then it is only 3 wires

    Mactec54


  8. #8
    Member
    Join Date
    Jan 2005
    Location
    USA
    Posts
    10764
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Quote Originally Posted by Muzzer View Post
    In N America, the "220V" supply is simply two 110V outlets that are 180 degrees out of phase, so you can achieve what you want with 3 wires - one 120V, the neutral connection and the other 120V. You get your 240V across the 2 phases and the 110V between either phase and neutral. The neutral is grounded at the utility transformer and is common to both phases, so the issue of a ground loop shouldn't arise. This is how I ran my European machine tools when I lived in Canada.

    If you look at the wiring of a modern kitchen in US / Canada, according to code there should be a "split" receptacle with both phases present in it. That's so you can run a kettle and another high current load (eg toaster) from the same dual receptacle (on different phaess) without tripping the 15A breaker. For Brits living in N America, that allows you to replace the std dual receptacle with a 240V receptacle so you can run a "proper" (3kW) kettle - tea drinking is a serious business for us!
    You are a little confused in NA the power supply is 240/120v supply and has been since the 60s

    Mactec54


  9. #9
    Member
    Join Date
    Mar 2017
    Location
    United States
    Posts
    280
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    I think you are best off getting an electrician to install a 220 sub-panel in the shop. The panel will have both legs of the 220 and that will let you also install a couple 220 and 110 breakers for whatever you have out there. It will also be properly grounded and fused for the job. It will also meet whatever the local codes are.



  10. #10
    Member gr-cnc's Avatar
    Join Date
    Dec 2018
    Location
    grand rapids
    Posts
    23
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Thanks, everyone. I ordered a new power supply from Antek Inc. It is an unregulated 77v 1000w PSU with additional 5, 12, and 24 volt outputs. That should take care of everything with one 240vac supply, I think.



  11. #11
    Member Muzzer's Avatar
    Join Date
    Apr 2014
    Location
    UK
    Posts
    46
    Downloads
    0
    Uploads
    0

    Default Re: Ideal wiring situation

    Sorry, I casually interchanged 110V and 120V in my haste - as you say, it should be a nominal 120V, +/-5%. The explanation about 120-0-120 is valid though, so if you want 120V and 240V you only require 3 wires plus ground.

    On the other side of the pond we keep changing the voltage so we never know whether to refer to it as 230, 240 or even 250V.



Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Ideal wiring situation

Ideal wiring situation

Ideal wiring situation