LiftMaster LMRRUL Monitored Retro-Reflective Photo Eye
The LiftMaster LMRRUL is a monitored retro-reflective photo eye used with compatible LiftMaster gate operators that require monitored entrapment protection. It is designed for UL 325 gate safety applications and is commonly installed as an external monitored photoelectric sensor on residential, commercial, and light industrial gate systems.
This sensor uses a powered photo eye on one side of the opening and a reflector on the opposite side. That makes it useful when power is only available on one side of the driveway or gate opening. The LMRRUL should be installed, aligned, and tested according to the gate operator requirements and the current safety layout for the site.
Compatible With
The LMRRUL is commonly used with LiftMaster gate operators that accept monitored entrapment protection devices, including many 2018 UL 325 LiftMaster gate operator applications. Compatibility depends on the operator generation, monitored safety input type, wiring configuration, and site safety requirements.
Common Compatible Operator Families
- Select LiftMaster 2018 UL 325 slide gate operators
- Select LiftMaster 2018 UL 325 swing gate operators
- Select LiftMaster LA series gate operators when monitored photo eyes are supported
- Select LiftMaster CSW series swing gate operators when monitored photo eyes are supported
- Select LiftMaster CSL series slide gate operators when monitored photo eyes are supported
- Select LiftMaster gate operators that accept monitored entrapment protection devices
Important Compatibility Notes
- The LMRRUL is a monitored retro-reflective photo eye, not a non-monitored photo eye.
- Do not use this sensor to bypass required monitored entrapment protection.
- Do not assume the LMRRUL and LMTBUL are interchangeable.
- The operator control board must support the monitored safety input being used.
- Photo eye placement should match the gate type, direction of travel, and entrapment zones.
Features & Specifications
| Feature / Specification | Details |
|---|
| Manufacturer | LiftMaster |
| Product Type | Monitored Retro-Reflective Photo Eye |
| Part Number | LMRRUL |
| Application | Monitored gate operator entrapment protection |
| Compatible Operator Type | Select LiftMaster gate operators that accept monitored photo eyes |
| Sensing Range | Up to 50 ft |
| Weather Rating | NEMA 4X |
| Heater | Built-in heater for outdoor performance |
| Included Components | Steel sensor hood, reflector hood, 10 ft wire, brackets, and mounting hardware |
| Weight | Approximately 3.3 lbs |
| Photo Eye Dimensions with Hood | 4.6 in H x 2.45 in W x 2.76 in D |
| Photo Eye Dimensions without Hood | 4.56 in H x 2.35 in W x 1.97 in D |
| Reflector Dimensions with Hood | 4.72 in H x 2.01 in W x 2.61 in D |
| Temperature Range | -40°F to 149°F |
| Notes | Alignment indicator and multi-view LEDs help with setup and troubleshooting. |
Also Known As / Related Part Numbers
- LMRRUL
- LMRRU
- LiftMaster monitored photo eye
- LiftMaster retro-reflective photo eye
- LiftMaster UL 325 photo eye
- LiftMaster gate safety sensor
Technician Note
Confirm the gate operator accepts the LMRRUL as a monitored safety device before installation. Retro-reflective photo eyes depend heavily on correct alignment, clean reflector placement, stable mounting, and proper wiring. If the gate operator reports a monitored safety fault after installation, check the sensor alignment, LED status, wiring terminals, reflector condition, and operator safety input programming.
Before Ordering, Confirm
- The operator requires or accepts a monitored retro-reflective photo eye.
- The gate opening is within the rated sensing distance.
- The site has a safe mounting location for both the sensor and reflector.
- The operator control board has the proper monitored safety input.
- The existing sensor is not an LMTBUL or another non-interchangeable safety device.
Professional Advisory
Gate safety devices are part of the entrapment protection system. They should not be bypassed or installed as a workaround for unsafe gate movement, missing edges, damaged wiring, or an operator that is not set up correctly. After installation, test the gate and all monitored safety devices before returning the system to service.
Important Ordering Warnings
- This is a monitored safety sensor and must be matched to a compatible operator.
- Rain, dirty reflectors, poor mounting, or misalignment can interrupt the beam.
- Safety device requirements vary by gate type and site layout.
- Similar-looking LiftMaster photo eyes may use different technology or wiring.
Questions & Answers
What type of photo eye is the LiftMaster LMRRUL?
The LMRRUL is a monitored retro-reflective photo eye for compatible LiftMaster gate operators. It uses a sensor and reflector instead of separate transmitter and receiver heads on opposite sides of the opening.
What is the sensing range of the LMRRUL?
The LMRRUL is commonly rated for sensing distance up to 50 feet, making it useful for many driveway gate and commercial gate openings when installed and aligned correctly.
Is the LMRRUL a monitored UL 325 safety device?
Yes. The LMRRUL is designed for LiftMaster gate operators that require monitored entrapment protection and is commonly used on 2018 UL 325 gate operator applications.
Does the LMRRUL need power on both sides of the gate?
No. The retro-reflective design requires power on the sensor side of the opening, with the reflector mounted across from it. The wiring and mounting still need to follow the operator instructions.
Can the LMRRUL replace the LMTBUL?
Do not assume the LMRRUL and LMTBUL are interchangeable. They are different monitored photo eye products with different installation requirements, range, and features.
