Blowout Coils for Traction Motors & Transit

Electrical arcing is when an electric current jumps from one connection to another across the gap between connections. Magnetic blowout coils are designed to suppress arcing by creating a magnetic field that can suppress and mitigate the arcing. Transit cars and subway cars use blowout coils as a way to control the common occurrence of arcing between connections of the car and the rail or guide.

Traction Motors

A traction motor is a DC electric motor providing the primary rotational torque of a machine or locomotive, usually for conversion of energy into linear motion (traction). The traction motors on DC electric and diesel electric transit and locomotives consists of two parts, a rotating armature, and a fixed field. The fixed field consists of tightly wound coils of wire fitted inside the motor case. The armature is another set of coils wound round a central shaft. It is connected to the field through "brushes" which are spring loaded contacts pressing against an extension of the armature called the commutator. 

Manufacturer of Blowout Coils

Stimple and Ward is a leading manufacturer of both blowout coils and electric coils used in traction motors for locomotive and transit systems. With over 50 Years of experience, Stimple and Ward has the experienced staff and equipment to manufacture coils for most traction motors.

Armature Images

Blowout Coils & Interpole Coils on Transit Cars & Traction Motors


Rotor Coils

5 Turn Blowout Coil                7 Turn Blowout Coils                  Interpole Coil          


Visit Gallery




Making RFQs Easy

To help you request a rotor quote, we have created a downloadable PDF worksheet enabling you to designate all your specifications and parameters. Simply download the form, fill it out and email or submit it on our contact form.

Edgewound Coils Rectangular EndsEdgewound Coils with Rounded Ends

Contact Us FoR More information or a quotation!  

If you have questions or would like to talk with an expert about our Blowout and Interpole coils for traction motors and transit use, please click the contact form at the right or call us at 1-800-792-6457 or 412-364-5200 today.

Scroll to Top