DC Contactors 1

[ojayl]

Hi all,
I am looking for a suitable contactor to handle 100VDC at 100A intial capacitive load with a 100VDC coil and another to handle 160VDC at 75A with a 160VDC coil. Under most circumstances the contactor will "make" under no load conditions due to a capacitor charging resistor but must be able to "break" under full load. This is a battery powered EV application and I have found a few 36/48/60 VDC units available from fork lift and golf cart parts suppliers but nothing at the higher voltages. I am trying to avoid tapping off the battery pack to get the lower coil voltages. Has anybody got any leads?
-Jay-

 

[RadarRay]

Last I knew, all the smaller (less than 500 amps) contactors for DC drives are by ABB. Jocelyn Clark used to make DC contactors, but I don't know if they exist any longer. Siemens also used to make contactors, we use to use them for 500 amps and over.
I never had to break a capacitive load but it seems to me this is much better than breaking a inductive load. That DC current in an inductive load just doesn't want to quit.

 

[GusD]

Hello ojayl.

Most DC Large contactors we use, are energized on full voltage and once energized, the voltage is dropped to just a few volts 5 or 6 volts to maintain it energized.We call it the Power saving mode.I don't know if it fits with your question or not ,but I hope it helps.

GusD

 

[jbartos]

Suggestion: Visit

http://www.saftronics.com

or

http://www.thomasregister.com

and type Contactors: DC under Product or Service, which will return 11 companies to contact, e.g.
PC & S, Inc.
149 Main St.
Stanhope, NJ 07874
USA
Tel: 800-523-9194
Fax: 973-448-1674
Or Call: 973-448-9400

or equivalent

 

[DougMSOE]

Cutler-Hammer still does but they are in their marine division.

 

[chitown]

I've been using the Siemens DC contactors for Dynamic Breaking circuits. They haven't failed me yet. The coil voltages you use are different but they do have them available for your application and they are a more rugid Nema design. Hope this helps.

 

[ScottyUK]

ojayl,

Have used clapper-type DC gear from Telemecanique, Siemens, and ABB.

The ABB equipment is approx. 50% cost of the near-equivalent Telemecanique part through our distributor, and the quality doesn't seem to have suffered, although I've not got any long-term experience of the ABB parts.

The Telemechanique product has been in service on a DC timestarter 110V DC, 160A FLC, peak current approx 450A. Pole faces are almost as good as the day they were installed 10 years ago.

Scotty.
The Siemens gear is good but expensive, so we don't use it much, but what we have bought has behaved flawlessly.

 

[ScottyUK]

ojayl,

Another company who have a range of DC contactors up to 1Kv and 1800A is Hubbell, Bedfordshire, England.

I've no experience with this manufacturer, just some info I had on the shelf. If you use any of Hubbell's equipment, please let me know any positive or negative feedback for future reference.

If you have an e-mail address, I can forward the catalogue as .pdf file.

 

[jbartos]

Suggestion: Visit

http://www.dialelectronicsweekly.com/product-58922.html

etc. for more info

 

[bmodrow]

One other good supplier of DC contactors is Microelectrica Scientifica located in Italy.

 

[Lakey]

Here in the UK, Albright contactors have a good reputation. I have used some and they have proved to be very reliable. Far as I know, Albright has agents all over the world.

http://www.albright.co.uk

Best regards,

 

[ScottyUK]

Hi Lakey,

Just had a look at Allbright's website. These contactors look quite different to the clapper type used in traction and similar applications - more like a heavily built AC contactor. Do you know how well they perform on heavy inductive switching, because I don't see any arc chute on them? Very compact for the ratings though.


Scotty.

 

[Lakey]

Hi Scotty,

I have seen them used in marine applications, such as winches and thrusters. I believe they also fit a wide range of EVs, as they manufacture to suit.

But to answer your question, yes I have seen then switch inductive loads.

I've just looked at the website, if you have an application in mind try "technical@albright.co.uk"

 

[jbartos]

Suggestion: The capacitive load "turn-on" will cause a short circuit current spike, since i(t)=C x dv/dt.
Therefore, the DC circuit shall be investigated for the short circuit "on close" current and the DC contactor rated accordingly, i.g. overrate it.