Mitsubishi Elevator Pit Limit Switch S3-1370 / EL-1375 / EL-7208

S3-1370, EL-1375, and EL-7208 are commonly used in Mitsubishi elevator pit and hoistway limit protection systems.

These switches are generally installed at designated positions inside the hoistway to monitor elevator travel limits and provide protective signals during operation.

They are commonly associated with:

• pit safety protection
• terminal travel monitoring
• deceleration control positions
• maintenance inspection systems
• elevator limit circuits

Some versions are used together with governor-related safety devices, while others are applied in travel limit and terminal protection functions.

Common Field Situation

In older Mitsubishi elevators operating in office buildings and residential towers, limit switch inspection is usually part of routine maintenance work.

Technicians may check these switches when encountering:

• abnormal terminal stop behavior
• intermittent limit circuit alarms
• inspection operation faults
• unexpected controller protection signals
• travel limit warnings during testing

Because these devices are exposed to dust, humidity, and long-term mechanical movement, contact wear and alignment issues may gradually affect performance.

Why Pit Limit Switches Are Important

The elevator pit is one of the most important safety zones inside the hoistway.

Limit switches installed in this area help provide protective signals when the elevator approaches designated travel positions.

A properly functioning limit system helps support:

• safe terminal operation
• maintenance inspection procedures
• controller protection logic
• travel monitoring functions

For this reason, maintenance companies often inspect pit switches during annual safety inspections and modernization projects.

Maintenance Notes

In some modernization projects, technicians replace the switch together with:

• mounting brackets
• wiring terminals
• protective covers
• travel actuator mechanisms

to improve long-term reliability.

When replacing a limit switch, correct mounting position is often just as important as the switch itself.

FAQ

What does a pit limit switch do?

A pit limit switch helps monitor elevator travel positions and provides protective signals within the hoistway safety system.

Can a faulty limit switch cause elevator shutdowns?

Yes. In some systems, unstable contacts or incorrect switch positioning may trigger protection signals or operational interruptions.

Why are terminal limit switches inspected regularly?

Because they play an important role in travel protection and overall elevator safety monitoring.

Installation Notes

Before replacement:

• switch model should match the original specification
• contact configuration should be verified
• actuator position should be checked carefully
• wiring terminals should be inspected for oxidation

Some Mitsubishi elevators use different limit switch arrangements depending on controller generation and hoistway design.