The LiftMaster K13-32087 is an RPM interrupter cup used as part of the operator speed and movement feedback system. The cup works with the RPM sensor to help the control board see that the motor and drive system are turning as expected. On commercial gate and door equipment, this feedback is important because the operator uses RPM information for travel control, obstruction response, and fault detection. When the cup is cracked, out of position, missing, or worn, the operator may run briefly and stop, show RPM or movement-related errors, or fail to read travel properly. This is a small part, but it belongs in a critical sensing area, so matching the original K13-32087 part and verifying the operator diagram matters before replacing it.
Compatibility should be verified by the operator model, parts diagram, and original part number because LiftMaster mechanical and enclosure parts can vary by operator generation.
| Manufacturer | LiftMaster |
|---|---|
| Product Type | RPM interrupter cup |
| Part Number | K13-32087 |
| Application | RPM sensor feedback component |
| Compatible Operator Type | Select commercial door and slide gate operators |
| Notes | Works with the RPM sensor; verify by operator parts diagram |
Inspect the sensor area before replacing the cup. A damaged RPM cup can be the symptom, but loose hardware, sensor misalignment, wiring trouble, or control-board faults can produce similar RPM errors.
If the operator is reporting RPM faults or stopping unexpectedly, the complete sensing system should be checked by a qualified gate technician before returning the gate to normal service.
It gives the RPM sensor a physical reference so the operator can monitor motor and drive movement.
A damaged or missing cup may cause RPM faults, short run cycles, inconsistent travel, or failure to complete a gate cycle.
No. It fits select commercial operator assemblies, so the operator parts diagram should confirm the part number.
No. K13-32087 is the interrupter cup, not the electronic RPM sensor or control board.
Yes. Sensor position, wiring, and the cup condition should all be inspected together.