LiftMaster K75-50189 Limit Switch Kit for Swing Gate Operators
The LiftMaster K75-50189 is a replacement limit switch kit used on select LiftMaster swing gate perimeter access systems. The limit switch system helps the operator stop at the proper fully open and fully closed positions. On a swing gate operator, worn limit switches or damaged limit hardware can cause inconsistent stop points, over-travel, nuisance shutdowns, or gate movement that does not match the expected limits.
This kit is commonly referenced for LiftMaster swing gate applications and is associated with related numbers Q166, Q055, and Q165. It is often described for CSW-style swing gate operator use, but compatibility should be confirmed by the operator model, generation, and parts diagram. Limit assemblies for swing operators can differ by cabinet style, control board generation, and limit hardware layout.
What This Part Does
The K75-50189 supports the operator system by servicing the limit switch kit area of the equipment. In the field, this type of replacement part is normally considered when the original component is worn, damaged, missing, electrically failed, mechanically loose, or no longer matching the required operator function. Because these parts are used on commercial and perimeter access systems, the exact fit can depend on model family, horsepower, voltage, control generation, enclosure style, and the original parts diagram.
Compatible With
The K75-50189 is commonly associated with Select LiftMaster swing gate perimeter access systems and CSW-style swing gate operators where Q166, Q055, or Q165 limit hardware is specified. Compatibility should be confirmed by model number, original part number, component layout, and the manufacturer parts diagram, especially where several similar LiftMaster parts exist for nearby models.
Common Compatible Products and Applications
- Select LiftMaster swing gate perimeter access systems
- Select LiftMaster CSW swing gate operators where the diagram calls for K75-50189
- Swing gate limit assemblies associated with Q166, Q055, or Q165 references
- Commercial and perimeter access swing gate operators using the matching limit switch kit
Compatibility Notes
- Use with select applications only; do not treat this as a universal LiftMaster replacement part.
- Match the operator model, horsepower or voltage where applicable, and the original part number before ordering.
- Similar-looking LiftMaster parts may use different connectors, shafts, mounting holes, cabinet locks, switch layouts, or electrical ratings.
- For commercial door and gate operators, confirm safety devices and operator operation after repair before returning the system to service.
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Limit switch kit |
| Part Number | K75-50189 |
| Application | Limit switch replacement for select swing gate operators |
| Compatible Operator Type | Select LiftMaster swing gate perimeter access systems |
| Common Related Numbers | Q166, Q055, Q165 |
| Notes | Match switch layout, operator family, and parts diagram before ordering |
Also Known As / Related Part Numbers
This part may be searched by several LiftMaster, distributor, or component-reference numbers. Related numbers are included to help with identification, but they should not be treated as guaranteed replacements unless the operator parts diagram confirms the match.
- K75-50189
- LM-K75-50189
- Q166
- Q055
- Q165
- LiftMaster swing gate limit switch kit
- CSW limit switch assembly
- Swing gate perimeter access limit kit
Technician Note
Before replacing the K75-50189, compare the original part label, mounting style, wiring or shaft layout, operator model, and parts breakdown. Commercial LiftMaster parts often share similar names but differ by horsepower, voltage, phase, logic generation, operator family, or cabinet design. If the failure involved binding hardware, damaged wiring, water intrusion, overheated components, or repeated faults, correct the cause before installing the replacement part.
Before Ordering, Confirm
- Original part number or related number on the failed component
- Exact LiftMaster operator model and product family
- Voltage, phase, horsepower, or logic generation when applicable
- Mounting style, connector layout, shaft size, switch layout, or cabinet lock style
- Parts diagram match for the specific operator version
- That the door or gate moves freely and the operator is not being overloaded
Professional Advisory
Commercial gate and door operator repairs should be performed with power disconnected and with the moving door or gate secured as required. Electrical components, brake circuits, control boards, and high-voltage motor circuits should be serviced by a qualified gate or door technician. Do not bypass monitored entrapment protection, limit switches, interlocks, or safety devices to force operation after a part replacement.
Important Ordering Warnings
- Do not order by appearance alone.
- Do not assume related part numbers are interchangeable without checking the parts diagram.
- Voltage, phase, horsepower, and logic generation must match where applicable.
- Limit, brake, control, and safety-related parts must be tested after installation.
Questions & Answers
What is the K75-50189 limit switch kit used for?
It replaces the limit switch hardware on select LiftMaster swing gate operator and perimeter access systems.
What related numbers are associated with this kit?
K75-50189 is commonly associated with Q166, Q055, and Q165 references.
Will it fit every LiftMaster swing gate operator?
No. Swing gate limit hardware varies by operator family and generation, so the parts diagram should be checked.
What symptoms can a bad swing gate limit switch cause?
It can cause over-travel, incorrect open or close stop points, repeated limit adjustments, or inconsistent gate travel.
What should be checked during replacement?
Check the switch mounting, actuator/cam position, wiring, control board input, and gate travel before returning the operator to use.
