NEMA C-Face Solenoid Actuated Brakes

The National Electrical Manufacturers Association (NEMA) defines basic design and dimension parameters based on the industry standards.

Stearns C-face general purpose brakes

General Purpose NEMA C-Face Motor Brakes

General purpose brakes are designed for mechanical loads and hard-to-start high inertia loads. They are commonly used on conveyors, belt-driven equipment, machine tools, pumps, compressors, etc.

View Products
Stearns Marine Duty Brakes

Marine, Maritime & Navy Brakes

Marine, maritime and Navy duty brakes are designed to meet the highest levels of corrosion resistance and performance. They are commonly used on various marine applications for offshore and military applications such as shipboard cranes, anchor winches, windlasses, etc.

View Products
Stearns Hazardous/Explosion Proof Brakes

Hazardous/Explosion Proof

Stearns manufactures a complete line of disc brakes designed from the hazardous locations defined in the National Electric Code (NEC). They provide protection from explosive gases or ignitable dusts in rigorous industrial environments.

View Products

Related Brake Types

What Are NEMA C-Face Brakes? 

NEMA C-face brakes are designed to allow for direct mounting with coupled equipment. NEMA brakes are used in various applications including material handling, marine, mining and other hazardous applications. 

solenoid brake

What Are Solenoid Brakes?

Stearns solenoid actuated brakes (SAB) are spring set, electrically released motor brakes that ensure automatic stopping and holding anytime power to the brake is interrupted.

Stearns is the market leader for solenoid brakes, and the primary supplier to all US motor manufacturers.

Advantages of Solenoid-Actuated Brakes

SABs have a compact design, delivering high torque in a small size. They are the standard choice for rapid-acting brakes in dynamic or holding applications and offer the widest range of options for specific applications.

Additional advantages include:

Unitized construction makes servicing friction discs easy - only screwdriver and wrench - so you can quickly do onsite friction disc replacement (as well as coils). SABs are also easily repairable with readily available replacement parts.

Explore solenoid brake types below, find a distributor or contact us with questions.

Solenoid Brake Enclosure Types

Stearns supplies solenoid actuated brakes in a variety of IP ratings.

brake solenoid

Solenoid Selection

The brake solenoid must be closely sized to load requirements for maximum service life:

  • An undersized solenoid (where load exceeds solenoid force) will fail through burnout of coil.
  • An oversized solenoid (where solenoid force greatly exceeds load) will fail prematurely through hammering of the plunger on the frame.

Stearns engineers are specialists in applying the proper solenoid to a particular application. You can profit from our experience by having a Stearns engineer review your requirements and determine the best possible solenoid for your particular application. Frequently, Stearns engineers are able to offer valuable recommendations which lower your solenoid costs and improve the performance of your products.

View or Download Solenoid Specs Contact a Stearns Engineer

Manually Adjusted Solenoid Actuated Brakes

Stearns manually adjusted solenoid brakes have all the features you want most in spring-set electrically released disc brakes, including:

Stearns offers three SAB series with a manually adjusted design:

self adjust mechanism inside self-adjusting solenoid brake

Self-Adjusting Solenoid Actuated Brakes

Stearns solenoid actuated spring-set disc brakes were the first in the industry to include an effective self-adjusting mechanism, and we are the ONLY brake manufacturer to offer self-adjusting brakes and produce our own friction discs.

Remote/inaccessible locations or high-cycling applications require a specially designed, low-maintenance brake that will operate at peak efficiency and provide uniform braking for long periods of time. Our self-adjusting SAB products are best-in-class because they require less maintenance and provide greater uptime on a torque-to-torque basis.

Stearns exclusive self-adjusting feature minimizes the major cause of brake maintenance by automatically compensating for friction lining wear.

This greatly reduces brake maintenance by eliminating the time required to periodically adjust the brakes for wear—especially if the brake is mounted on a hoist on the ceiling of a plant, or in another hard-to-reach area. 

In addition, self-adjusting brakes are well suited for applications where rapid cycling requires frequent resetting of the solenoid air gap. Automatic adjustment also eliminates the potential for errors with hand adjustment. 

main components of self-adjusting solenoid disc brakes

Our self-adjusting solenoid brakes can be easily modified to suit your particular application. Depending which series you select, they can be directly mounted on motors ranging in size from NEMA 182TC through NEMA 505C.

Many modifications for special application requirements are available. We also have models specifically designed for marine and maritime applications (ABS Type Approval Certified). There are nine series of Stearns self-adjusting brakes to select from:

Double C-Face Disc Brake Couplers

Stearns disc brake couplers provide maximum versatility, allowing you to add a solenoid actuated brake to a C-face motor with a single shaft extension. Using our reliable brake couplers, you can couple a C-face motor to a C-face gear reducer.

Explore Double C-Face Coupler Brakes

Solenoid Brakes with Optional Encoder

Stearns solenoid actuated brakes are available with an internally mounted encoder. Encoders can also be adapted externally.

Stearns brakes with internal encoders should be purchased through the motor manufacturer, as a special shaft length and diameter may be required. To order the brake-motor package, specify the brake model and encoder option.

View Encoder Brake Specs

Solenoid Washdown Brakes

In addition to our application-specific solenoid brakes at the top of this page (marine, maritime, Navy, and explosion proof) we also offer solenoid brakes that meet AAA Dairy Standards and other food industry washdown requirements. Our 56,000 Series and 87,000 Series brakes feature stainless steel hardware, neoprene gasketing and FDA-approved white epoxy paint or stainless steel enclosure.

Solenoid Brake FAQ

Get answers to common questions about our solenoid actuated brakes.

How do solenoid brakes work?

Stearns solenoid actuated brakes are spring set motor brakes controlled by an electrical solenoid. A solenoid is a device that converts electricity into mechanical motion, using a wire coil and plunger inside a housing. When an electrical current flows through the copper wire it creates a magnetic field. The housing concentrates the magnetic field, drawing the plunger down and releasing the brake. When the electric current is turned off, the spring engages the brake.

Does Stearns offer any circuit protection for EMI generated by a solenoid actuated brake coil?

Yes, we can provide a line filter. Just call Stearns product support and advise the part number for the brake coil, or the model number for the brake.

Does Stearns supply coils for special voltages for solenoid actuated brakes?

Yes. Please consult the Stearns catalog for standard coil voltages for each model and size of brake.  Stearns coils are manufactured in house in Cudahy, WI. We have the capability to design and manufacture to OEM specifications for application specific requirements. Contact Stearns for details and to discuss your applications.

What do the colors of the pressure spring mean?

Each pressure spring for Stearns SABs is color-coded to indicate the torque rating of the brake, for example: 

Why can’t I adjust the solenoid air gap on my 81 or 82 series brake?

Most likely the caution warning on the support plate that instructs to secure the solenoid plunger to the solenoid frame prior to loosening the support plate mounting screws was not followed, and the self-adjust mechanism allowed the lever arm to spring out from the support plate. In this case, the lever arm may need to be reset. See reference PDF.

Why can’t I adjust the solenoid air gap on my 87 series brake?

Most likely the caution warning on the support plate that instructs to secure the solenoid plunger to the solenoid frame prior to loosening the support plate mounting screws was not followed, and the self-adjust mechanism allowed the lever arm to spring out from the support plate. In this case, the lever arm may need to be reset. See reference PDF or video tutorial.

Why did the cotter pin in my 87 series brake shear off?

The cotter pin in the 87,000 series brake is there as a gentle keeper to keep the solenoid link from sliding off of the solenoid lever. It sees no impact or side load. When the pin is installed at the Stearns factory, it is slightly spread open just enough to keep it from slipping through the cotter pin hole. If the cotter pin has broken, it can only be the result of weakening the cotter pin, by either bending it too far, removing and reinstalling it and thus stressing the metal.

Solenoid Actuated Brakes in as Few as 5 Days

Solenoid actuated brakes in our Signature Series are based on industry demand for standard features and can be received as quickly as five business days. Our Signature Series program improves operational flexibility and reduces risk with locally manufactured and supported product lines. 

Filter through our Signature Series SAB products by lead tIme and other popular product features to request a quote. Our experts are available to partner with you to find the best products for your applications. 

Shop Signature Series SAB Contact a Product Expert

Why Stearns?

Stearns is the only supplier of MSHA certified motor brakes - MSHA approved and certified these products for use in underground coal and gassy mines. 

Find a Stearns NEMA C-Face Brake by Industry

Our NEMA C-face brake selection includes both solenoid actuated brakes and armature actuated brakes.

Agriculture | Cement & Aggregate | Crane & Hoist | Elevator | Food & Beverage | Forestry | Forklifts | Gas & Oil | Marine | Material Handling | Medical | Mining | Packaging | Special Vehicle Market | Water Processing