Contactors

[ccamts]

Hi
If any body could advice me, how to specify the rating of a motor contactor, I mean what the format stands for like in one of the threads I had
3RT10 15-1AB01 24V AC coil

how to read it.

# 2, What is the max, limit of current or voltage that we can use magnetic contactors, what vol or current is assigned for vacuum contactors and when do we go for a relay based protection for motors and I assume that is MCC.
I would appreciate the response.
Thanks

 

[jraef]

Contactors for use in motor circuits have a motor rating associated with them. That rating will be in kW or HP. No other rating should be used, because it is not indicative of the special circumstances involved in AC motor starting. So as far as 'specifying" one, just specify the kW rating of the motor. IEC contactors also have a duty rating associated with them, which is totally dependant on what you need the contactor to do, i.e. how many operations, lifespan, reversing etc. Every contactor manufacturer I know of has a selection chart in their catalog information. I suggest you start there.

The part number you posted looks to be a Siemens contactor. Look in their catalog for "how to read it".

Your second question is like asking "how high is up?". Voltage and current ratings are whatever you select them to be. By "magnetic" contactors I assume you mean air-break contactors because all contacotrs are operated by magnets. You can get air break contactors at any size and voltage, but the size of them get5s somewhat rediculous at higher voltages. You can also use a vacuum contactor at 24VAC if you like, but it will cost a lot of money for no good reason.

Why don't you pin this down to a specific question?

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[ScottyUK]

jraef,

Confirm that as being a small Siemens contactor from their Sirius range in IEC-land. The range is 3RT10, the rest is an encoded description of the contactor. You need the manufacturer's catalogue to decode it. Some of the standard terms you should find common across ranges are ratings like AC-1, AC-3, maybe AC-4 and AC-5 as well. Most of the catalogues have a few words on this also.



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One day my ship will come in.
But with my luck, I'll be at the airport!

 

[ccamts]

Thanks Jraef and scotty, Rest I would try to figure out my self otherwise would bother you guys again.
Thanks

 

[ScottyUK]

Since you seem to have a go-see attitude, I'll warn you off the Siemens website. It is awful, probably the worst website belonging to a multinational company that I've ever used. What an accolade!

Telemechanique (Schneider) have a great website, though I think their products are in many cases dreadful. The following links might help: the second one gives a lot of good background info and explanation.

http://www2.schneider.co.uk/seweb2/internet/literature.nsf/luLibrary?open

http://www2.schneider.co.uk/seweb2/...B5299731B9E6A1358025705200389F74?opendocument

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One day my ship will come in.
But with my luck, I'll be at the airport!

 

[itsmoked]

Telemechanique!?!? Man! Different view points.. I was so annoyed by their site I had to express it to them on the phone.

 

[ScottyUK]

I guess you are still a Siemens website virgin - once you'be been in hell, everywhere alse looks great...


----------------------------------

One day my ship will come in.
But with my luck, I'll be at the airport!

 

[itsmoked]

hehehe