Both 1LS and 2LS Operated

What does >1LS + 2LS ! mean?

This blinking event message indicates that both Limit Switch 1 (1LS) and Limit Switch 2 (2LS) are simultaneously in an operated state, blocking elevator movement. This condition is typically indicative of an abnormal car position or a wiring fault within the OTIS 2000 Controllers MCS120/MCS220 system.

• Incorrect car positioning leading to simultaneous actuation of both limit switches.
• Short circuit or cross-wiring in the limit switch circuits.
• Mechanical fault causing both switches to remain in an operated state.
• Faulty individual limit switches, causing one or both to be stuck in an actuated position.

Click steps to track your progress.

1. 1

   Verify the elevator car's actual position relative to the limit switches 1LS and 2LS.

2. 2

   Inspect 1LS and 2LS for physical damage or simultaneous mechanical actuation.

3. 3

   Check wiring for 1LS and 2LS circuits for short circuits or incorrect connections.

4. 4

   Measure the individual state of each limit switch contact to identify if one is stuck in an operated position.