LiftMaster K71-B240 Internal Brake Solenoid 240V for SL575GL Slide Gate Operators
The LiftMaster K71-B240 is a 240V internal brake solenoid replacement kit for select LiftMaster commercial slide gate operator brake systems. It performs the same basic job as the 120V K71-B120 family, but it is built for the 240V brake circuit specified on certain operators. The solenoid pulls the internal brake release mechanism during operation and allows the brake to hold when the operator stops.
This part is most commonly referenced for SL575GL slide gate operator brake service. Some listings also group it with broader LiftMaster commercial slide gate operator brake parts, but the correct fit depends on the exact model and brake assembly. The part should not be chosen only because the operator is an SL-series slide gate operator; voltage, phase, brake hardware, and older GL/U/UL production differences matter.
Use K71-B240 when the original solenoid, parts diagram, and operator nameplate support the 240V internal brake solenoid family. If the solenoid coil failed because of a wiring issue, incorrect voltage, or brake drag, replacing the coil without correcting the root cause can lead to another failure.
Compatible With
This part may be used with select LiftMaster slide gate operators that require the 240V K71-B240 internal brake solenoid.
- LiftMaster SL575GL slide gate operator applications where K71-B240 is listed
- Select LiftMaster commercial slide gate internal brake assemblies calling for 71-B240 or 71B240
- 240V slide gate brake circuits that use the K71-B240 internal solenoid family
- Not a substitute for K71-B120 120V, K71-B3PH three-phase, K71-B120H / K71-B240H hoist solenoids, or K22-series Logic 5 brake solenoids
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Internal brake solenoid replacement kit |
| Part Number | K71-B240 |
| Voltage | 240V |
| Application | Commercial slide gate operator internal brake system |
| Compatible Operator Type | Select LiftMaster SL-series slide gate operators |
| Common Model Reference | SL575GL where specified |
| Notes | Voltage-specific brake solenoid |
Also Known As / Related Part Numbers
- K71-B240
- 71-B240
- 71B240
- LiftMaster 240V internal brake solenoid
- LiftMaster SL575GL 240V brake solenoid
Technician Note
A 240V internal brake solenoid should only be used on the matching 240V brake circuit. If the original part number is missing, confirm by the operator parts list and wiring diagram rather than guessing from appearance.
Before Ordering Checklist
- Confirm the operator calls for K71-B240
- Confirm the brake circuit is 240V
- Compare the brake assembly to the parts diagram
- Inspect brake hardware for binding before energizing a new solenoid
- Verify gate stopping, limits, and safety devices after repair
Professional Advisory
Commercial slide gate brake repairs should not be treated as simple plug-in service. Incorrect brake voltage, incorrect adjustment, or missing safety checks can create dangerous gate movement. Use a qualified technician when in doubt.
Product Questions & Answers
What is the K71-B240 used on?
It is used on select LiftMaster commercial slide gate internal brake systems, most commonly SL575GL applications where the diagram calls for K71-B240.
Is K71-B240 a 240V part?
Yes. K71-B240 is the 240V internal brake solenoid family.
Can I use K71-B120 instead?
No. K71-B120 is the 120V version and is not interchangeable with K71-B240 unless the operator has the matching brake circuit and parts diagram.
What should I check before ordering?
Check the operator model, voltage, brake assembly, original solenoid number, and replacement parts diagram.
Can a bad brake solenoid make a gate hum?
Yes. A failed or wrong-voltage solenoid can cause humming or failure to release, but mechanical brake binding and wiring problems can cause similar symptoms.
