Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

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

Connector/receptacle/plug suitable for motor power connection 6

Status
Not open for further replies.

PaulKraemer

Electrical
Jan 13, 2012
145
US
Hi,

I am working on a project in which I will be using a variable frequency drive to drive a ½ HP asynchronous AC induction motor. The drive will be inside a control panel that will most likely remain in a single location. The motor will be located in separate assembly that (when in use) will be approximately 6-12 feet from the Control Panel. When not in use, the intention is to disconnect and remove the motor assembly.

For the power connection from the drive to the motor, the drive manufacturer recommends the cable types shown in the following image:

PowerCableTypes_udn12v.png


The drive manufacturer lists 16 AWG as typical for nominal drive current and the the motor specs list the full load amps (at 230 VAC) as 1.6 amps. Being the motor assembly will have to be removed occasionally, I’d like to make it as easy as possible to disconnect it from the Control Panel. With this in mind, I’d like to run the power cable from the motor to some sort of connector/receptacle on the outside of the motor assembly, and to terminate the cable coming from the Control Panel with a mating connector/plug.

I was wondering if anyone here can recommend a type of connector/receptacle/plug that would be suitable for this application.

Thanks and best regards,
Paul
 
Replies continue below

Recommended for you

So this is intended to be flexible cable then? Given that you are using AWG sizes, can we assume the installation in the US or Canada? is there a possibility of the connection being pulled while energized?




" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
Hi jraef,

Thanks for your response. I do envision this as a flexible cable, and the installation will be in the US (California).

I'd say that we will be able to route the cable and locate the connectors so that it would be very unlikely that the connection would be inadvertently pulled while energized (by someone tripping over it for example). However, I can't think of a way that I can make it impossible for this to happen if someone intentionally wanted to pull the plug. I can say that there is no reason why this should or would be done during the intended operation of the equipment.

At the moment, I am just trying to think of a way that I can neatly and effectively get my cable from one location to the other, while providing a simple means to disconnect it at one end if/when we want to move (or remove) the associated equipment. Of course, I do have to make sure that whatever I do will comply with any applicable codes and regulations.

I appreciate your help.

Best regards,
Paul
 
I don't usually see them on that small of a motor, but there are specific motor disconnects that incorporate safety features to prevent something dangerous from happening.

I am most familiar with this line of disconnect products,
I have also used motor disconnect systems from Eaton, T&B and others.

Hope that helps, MikeL.
 
You may find something in an explosion proof line.
Link
The disconnect switch must be OFF before the receptacle may be inserted or removed.
I have also seen a type where the receptacle is inserted and then must be turned to energize.
I'll let you do the Googling for a smaller version.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Paul,
Even outside the hazardous area stuff, I think that some of the IEC 60309 switched-sockets have a threaded "bushing"(to prevent accidently pulling out) and are mechanically interlocked (so they turn off if you do pull them off). 60309-4, perhaps. I would expect there would be an equivalent in ANSI world.
John.
 
Probably a bit on the heavy side for your application, but top quality and very rugged:
The Cavotec range incorporate an early-breaking auxiliary contact which kills the power circuit before the main poles disconnect.

These smaller connectors were developed by Hawke before Hubbell bought them, decent quality and been around a while:
 
Hi jraef, MikeL, Bill, Aussiejohn, and SkottyUK -

Thank you for your suggestions. They were all a big help as I now have quite a few options to look into. I appreciate your help!

Best regards,
Paul
 
SMS, Appleton and Patton and Cooke are three more vendors of portable cable connectors.

Look for pilot wire terminals that can be used to complete the control circuit. Alternatively, use a Startco ground check relay that disables the controls unless the ground to the motor is confirmed.

I believe Cavotec makes connectors that allow the shield of a cable to be kept continuous through the connector.
 
Thank you LionelHutz - I will check out what they have to offer.

Best regards,
Paul
 
For small loads like that, another option that I have used and like is what’s commonly referred to as a “Harting connector”. They are especially good when using shielded cable as they will have additional pins that will keep the shield separate from the ground conductor. Harting is a brand name that is the originator of this style, but it’s become so popular now that there are several competitive versions out there which are interchangeable, so it’s become somewhat of a generic term for the type of connection system with a locking bale.







" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
Thank you jraef - I will check those out as well. I appreciate your help.

Best regards, Paul
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top