Non mercury sealed A/C motor contactors

[jcromwell]

We are looking for a solution for contactor failure in a highly contaminated environment. Mercury displacement contactors are not an option. The majority of sealed A/C motor contactors in this category seem to be for the aerospace and military. Highly specialized products for these industries are not economical to say the least. Any information to point us in the right direction would be great.

Application: 5-15 HP 208VAC 3Phase continuous duty.

 

[davidbeach]

Normal starter in a NEMA-12 enclosure that is pressurized with clean dry air.

 

[itsmoked]

Or an appropriately heatsinked SSR? 15HP might be a stretch.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[jraef]

Sealed in what way? The entire operating mechanism or just the contacts (the arcing and sparking parts)? If it's just the contacts you are worried about, you can get small(ish) vacuum contactors. Joslyn Clark has a series of Low Voltage vacuum contactors called their MCVAC line that goes as small as NEMA size 4 / 135A, which is 40HP at 208V. It's a bit overkill for your application, but probably one of your only reasonably priced solutions. Siemens has LV Vacuum contactors as well, but the smallest is 150 HP / 225A.

Joslyn Clark MCVAC contactors


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