Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations MintJulep on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

three phase motor with seven wires 2

Status
Not open for further replies.

Errol

Electrical
Jul 16, 2003
3
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
 
Replies continue below

Recommended for you

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"


 
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.....
 
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.

 
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
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor