×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Elementary motor wiring
2

Elementary motor wiring

Elementary motor wiring

(OP)
I have a confidential project involving a 2hp 3 phase motor.
The motor will be inside a fiberglass housing. What type of wire must I use inside the housing? Must I have a junction box where the wires terminate?

My concern is based on the fear that thre will not be enough room to run heavy cable in the not-too-big interior.

RE: Elementary motor wiring

Hello insideman
what is your voltage supply? 230, 460 etc.

RE: Elementary motor wiring

(OP)
Thanks for responding. 230/460 volts.

RE: Elementary motor wiring

Hello Insideman,

One 3 Phase  2 HP Squirrell Cage  Motor will drawn at 230 Volts 6.8 Amperes at Full load.  Normally this small motors use Y or 2Y, Then you will need only four wires, 3 for phase and 1 for earthing. Use 4 wires EXAR 3562 AWG 22 -600 volts Class F(150 Grades C),manufactured by CHAMPLAIN CABLE.I don´t think you need the junction box because you could open a small hole on the fiber glass housing and pass the power wires from outdoor to indoor housing and then connect with the motor, I think you could remove the motor´s conection box.The housing hole can be sealed and closed with Silicone compound.

Regards

Petronila     

RE: Elementary motor wiring

Insideman, I'm not sure I understand your particular configuration (fiberglass housing) and your statement "heavy cable" but will try to give a suggestion. Corrections Welcome?
Large cables lead me to assume that there may be voltage drop "distance from the 3ph 230/480 volt source". If this is the case you could install a Junction Box some where close to/on the outside of the (fiberglass housing). At that point you could use 1/2in. flex to your motor connection box and use smaller single conductors (#14Awg)  for your connection at the Motor. Again I'm not sure of your particular configuration but I don't think you would want an installation with out installing some type of raceway (Flex/Conduit) for your Motor supply cables/conductors. !! SAFETY!!

Again, Corrections Welcome
12Fish   

RE: Elementary motor wiring

(OP)
Thanks for the help. Both of you have given me valuable tips. I must check the cable reccommended to make sure it can be wiggled into place without too much swearing.

RE: Elementary motor wiring

Motors tend to overheat when the ventilation is restricted by things like close fitting fiberglass boxes.
yours

RE: Elementary motor wiring

I agree with waross, some consideration should be given to the ventilation requirements of the motor. If air flow is restricted the motor will most likly over heat. Also, depending where you live or where this unit will be used, there may be some electrical code requirements which need to be addressed.

RE: Elementary motor wiring

(OP)
Ventilation is taken casre of nicely.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources