Liftmaster K75-12494 Brake solenoid Kit, 120V
The LiftMaster K75-12494 is a 120V brake solenoid replacement kit for select LiftMaster commercial door operators. In a brake-equipped operator, the solenoid pulls the brake linkage so the brake can release while the motor is running, then allows the brake to hold when the motor stops.
This part is voltage-specific. Commercial door operators can use similar-looking brake solenoids with different voltage ratings, and installing the wrong one can damage the brake circuit or keep the brake from releasing properly.
Compatibility and Application
Parts breakdown references show K75-12494 as the 120V brake solenoid in the LiftMaster medium-duty jackshaft brake section. Other commercial door operator listings describe it broadly for select LiftMaster commercial door operators and commercial access applications where the parts diagram calls for this exact 120V solenoid.
- Select LiftMaster MJ medium-duty jackshaft operator brake assemblies
- Select LiftMaster commercial door operators where K75-12494 is specified
- Commercial brake assemblies using the matching 120V brake solenoid circuit
- Medium-duty logic operator brake service applications when the diagram calls for K75-12494
Important Fitment Notes
- Not the same as K75-12492 115V brake solenoid listings
- Not the same as K22-120 unless the diagram specifically allows that service part
- Not the same as K22-240 or other 240V brake solenoids
- Not a cure for all brake problems if the linkage, brake disc, spring, or control voltage is faulty
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Brake solenoid replacement kit |
| Part Number | K75-12494 |
| Voltage | 120V |
| Application | Commercial door operator brake release circuit |
| Compatible Operator Type | Select LiftMaster commercial and medium-duty operator brake assemblies |
| Function | Energizes to release the brake during operator travel |
| Notes | Confirm solenoid voltage and operator service diagram before ordering |
Also Known As / Related Part Numbers
- K75-12494
- 75-12494
- LiftMaster 120V brake solenoid
- LiftMaster brake solenoid kit 120V
- Commercial door operator brake solenoid
Related Parts in the Same Operator Family
- K75-12492 - 115V brake solenoid reference in some parts lists, not the same voltage
- K22-120 - 120V brake solenoid reference listed in some brake service diagrams
- K22-240 - 240V brake solenoid reference, not the same voltage
- K17-10363 - brake pulley/disc assembly in select medium-duty brake diagrams
- K75-10359 - brake mounting plate in related brake assemblies
Technician Notes
A brake solenoid problem can show up as the motor running but the operator not moving, a loud hum from the brake, brake chatter, overheating, or a door that will not release cleanly. The solenoid is only one part of the brake system.
Before replacing a solenoid, inspect the brake linkage, mounting plate, spring, brake disc, mechanical binding, and incoming control voltage. A stuck brake can overheat a motor if the operator keeps trying to run.
Before Ordering Checklist
- Confirm the old solenoid is rated for 120V
- Confirm the service drawing lists K75-12494
- Inspect the brake linkage and mounting plate for bending or wear
- Check the control voltage at the solenoid circuit using safe diagnostic procedures
- Do not substitute a 115V, 230V, or 240V solenoid
Professional Advisory
Brake service on a commercial door operator should be handled by a trained technician. Secure the door, disconnect power before service, and test the brake and safety devices after repairs.
Product Q&A
What does the K75-12494 brake solenoid do?
It releases the operator brake when energized so the motor can move the door, then allows the brake to hold when the motor stops.
Is K75-12494 a 115V or 120V solenoid?
K75-12494 is listed as a 120V brake solenoid. Do not confuse it with 115V, 230V, or 240V brake solenoid references.
Can a bad brake solenoid make the motor hum?
Yes, but a hum can also come from a bad capacitor, stuck brake linkage, low voltage, or a seized drive component. The full brake and motor circuit should be checked.
Does this kit include the complete brake assembly?
This listing is for the brake solenoid kit. It should not be treated as a full brake assembly unless the package contents are confirmed separately.
Should the brake be adjusted after installation?
The brake function should be inspected and tested after service. A qualified technician should confirm release, hold, and safe door operation.
