Description

Nanjing Zhuye Elevator Parts
Elevator Limit Switch S3-1370 – Installation, Operation & Replacement Guide

Introduction
In every elevator safety chain, the limit switch is the last physical line of defense. Nanjing Zhuye Elevator Parts presents the S3-1370 mechanical roller-lever limit switch, engineered for medium/high-speed passenger elevators and heavy-duty freight lifts. Certified to CE, UL and EN81-20/50, this 800-word guide (≈850 words in English) walks you through correct use and scheduled replacement, helping global web-shop owners maintain units with zero downtime.

1. Product Highlights
– Double-break silver-alloy contacts: 5×10⁶ operations at AC-15, 3×10⁶ at DC-13.
– IP66 sealed body, –25 °C to +80 °C, proven in plateau and coastal salt-mist.
– 1NO+1NC positive-opening contacts, ≥0.5 mm travel, EN60947-5-1 compliant.
– V0 flame-retardant housing, 304 stainless roller lever, 800 N tensile, lube-free for life.
– Drop-in replacement for legacy Otis, Kone and Mitsubishi switches—installs in five minutes.

2. Five-Step Installation
Step 1 Lockout/Tagout
Isolate main power, lighting and UPS; verify no residual 110 V/220 V with a multimeter.

Step 2 Positioning
Orient the base arrow in the car-travel direction; keep roller centre line perpendicular to the strike plate within 0.5 mm. Fasten with two M6 bolts plus spring washers at 10 N·m.

Step 3 Wiring
Connect COM to safety-chain common, NC in series with upper-limit circuit, NO to remote diagnostics. Wire size 0.75–1.5 mm², strip 6 mm, crimp ferrules and insert into cage clamps—tug test for tightness.

Step 4 Stroke Setting
Jog the car slowly toward the terminal. Adjust the M5 hex nuts until the contacts trip at 1.5–2 mm roller depression; positive opening must occur within an additional 5 mm travel. Check opening distance with a 0.05 mm feeler gauge.

Step 5 Functional Test
Manually depress the roller; the controller should display “upper limit triggered”. After release, contact resistance must be ≤25 mΩ. Repeat ten consecutive cycles, then restore normal speed.

3. Daily Maintenance Tips
– Monthly: inspect roller surface for cracks or grease; replace if serrated wear appears.
– Quarterly: measure contact resistance with a FLUKE 289; >50 mΩ means clean or replace.
– Annually: verify positive-opening travel before government inspection.
– Never spray WD-40—it swells the IP seal.
– When seismic or fire service is added, wire a second S3-1370 in series for redundancy.

4. Replacement Interval & Discard Criteria
Interval:
– First change 3 years after hand-over;
– Then every 2 years or 2×10⁶ runs, whichever comes first;
– 24/7 hospital/metro lifts: every 1 year.

Discard if:
– Lever bent >1 mm or roller axial play >0.3 mm;
– Insulation <100 MΩ at 500 V;
– Housing cracked or seal ring missing;
– After any terminal-impact event, even if visually sound.

5. Four-Step Replacement
Step 1 LOTO, hit emergency stop, remove old switch and photograph wire numbers.
Step 2 Reverse the “Five-Step Installation”—physical mounting takes 30 s.
Step 3 Run five slow-speed limit tests with a handheld debugger; confirm no rollback.
Step 4 Complete the online S3-1370 Replacement Log; Nanjing Zhuye cloud auto-schedules the next alert.

6. FAQ
Q1 Can I replace only the roller?
A: Roller and lever are riveted—field re-assembly cannot guarantee concentricity; replace the entire unit.

Q2 “Click” noise during run?
A: Usually a worn strike-plate angle; check chamfer <0.5×45°.

Q3 Difference from old S3-1360?
A: S3-1370 increases silver thickness from 0.8 mm to 1.2 mm, boosting life 30 %; same footprint for instant upgrade.

Conclusion
Elevator safety has no “close enough”. Treat the S3-1370 as a consumable, not a lifetime part; scheduled replacement costs less than one unplanned outage. With 15 years devoted to limit switches, Nanjing Zhuye Elevator Parts delivers “zero-defect” shipments to 78 countries. Add to cart today and keep your elevators running safely—up and down—for the next decade.