×
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

three phase motor with seven wires
2

three phase motor with seven wires

three phase motor with seven wires

(OP)
hi
anyone familliar with this one

i was in a little bit of a Jam so i borrowed a 400 volt 3 phase 5 hp submersible pump from somebody's (dead stock) storeroom.

trouble is the pump cable consists of seven wires and no markings and i can't seem to figure out what all of them are for.

I can identify the ground wire green/yellow - but there is also continunity between it and a solid yellow .

there is also continunity between three leads (about 0.4 ohms) which i believe are the  windings (connected in Y)

and the rest I can't figure out - any ideas out there?

thanks

RE: three phase motor with seven wires

hi
 Two wires will almost certainly be a thermal overload device!!
                  jeff
             www.motors-direct.co.uk

RE: three phase motor with seven wires

If it is a Flygt or ABS submersible, they may be a combination thermal device and a seal failure sensors. If so they would have resistance on them because they are capacitive sensors, and adding ground still only comes to 6 wires.

It may also be that your motor is set up for Y-Delta starting, so all 6 leads would be brought out. However, you would show 3 pairs as having continuity, not 3 wires.

Any help from the pump mfgr?

"Venditori de oleum-vipera non vigere excordis populi"


RE: three phase motor with seven wires

3 leads will be the motor windings the ones you said were about 0.4 ohms

1 lead will be earth

2 leads will be thermal protection either thermistors 150-160 ohms, or klixons 0.1 ohms

1 lead will probably be a moisture sensor, which should not have continuity with the earth lead, unless the sensor is damp

also be aware that its possible the thermal protection isnt physically connected to the incoming cables, so you may not get any readings between some of the leads.....   

RE: three phase motor with seven wires

its a simple analysis, A 5 hp motor would never reads a 0.4 ohms,  this should read above 0.4 ohms.
 
 jammy, has a good points but knowing the unit is only a 5 hp motor. Errol, to clear up your anxieties about the cables..

  why shouldn't you open up and see what is really the actual connection. if this motor is made by FLYGT,im sure it has a terminal box provision above its lifting handle so you will easily check and identify the wire connections without opening the inner parts. take note that most submersible pump are oil-filled winding. be sure not to leak out the oil inside.
  

RE: three phase motor with seven wires

Errol, we used similar pumps in coal mining.  The yellow wire is used in a ground monitor system and is connected to the frame as is the ground, but in a different place.

ontheroad

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