Description

• Precision Speed Detection: Accurately monitors elevator speed with a tolerance of ±0.05 m/s, triggering the safety gear within 0.3 seconds when overspeed occurs—preventing car free fall or excessive impact.

• Dual Safety Protection: Combines mechanical (centrifugal) and electrical (switch) protection: the pre-overspeed switch activates an alarm at 105% of rated speed, while the emergency switch cuts power and triggers safety gear at 115%—providing layered safety.

• Perfect Compatibility: Mounting dimensions (bolt hole spacing: 120mm×80mm) and rope groove specifications (groove diameter: 20mm) align 100% with Otis’s original speed limiter brackets and safety ropes, requiring no modifications to the elevator’s safety system.

• Durable Performance: The cast iron housing has an IP54 dustproof and waterproof rating, while the gear train uses high-carbon steel (45#) with anti-rust coating—suitable for long-term use in elevator machine rooms with varying temperatures (-10°C to 60°C).

• Visual Inspection: Check the cast iron housing for cracks, the rope groove for wear (depth reduction ≤1mm is acceptable), and electrical wires for fraying or loose connections.

• Manual Rotation Test: Power off the elevator, disconnect the speed limiter rope, and rotate the limiter’s handwheel by hand—feel for smooth rotation (no jamming) and listen for abnormal noises (grinding indicates gear wear).

• Speed Switch Test: Use a speed simulator (supplied by Nanjing Zhuye Elevator Parts) to simulate elevator speeds:

• • At 105% of rated speed: Confirm the pre-overspeed switch activates (check via the elevator’s control panel alarm).

• • At 115% of rated speed: Verify the emergency switch triggers (power cuts off, safety gear engages).

• Rope Tension Check: Ensure the safety rope is properly tensioned (deflection ≤5mm when pressed with 50N force)—adjust the tension weight if needed (follow Otis’s rope tension guidelines).

• Safety First: Execute the Lockout-Tagout (LOTO) procedure: Shut down the elevator’s main power, secure the elevator car at the top floor (to relax the safety rope), and place warning signs in the machine room and elevator lobby.

• Confirm Compatibility: Use Nanjing Zhuye Elevator Parts’ free online tool (via their official website) to verify the TAB20602K4 matches your elevator’s rated speed and model (e.g., “Otis Gen2 2.0 m/s”).

• Gather Tools: Wrench set (14mm/17mm), torque wrench (20-30 N·m), rope cutter, new safety rope (if replacing, supplied by Nanjing Zhuye), and the new TAB20602K4 speed limiter.

• Disconnect the Rope: Remove the tension weight from the safety rope, then disconnect the rope from the old limiter’s rope groove (mark the rope’s direction to avoid reverse installation).

• Disconnect Electrical Wires: Label the two electrical switches’ wires (e.g., “Pre-overspeed: Red-Black”, “Emergency: Blue-White”) and disconnect them from the elevator’s control system.

• Remove Mounting Bolts: Use the wrench to loosen the 4 mounting bolts (M12) securing the old limiter to the bracket, then lift the old unit out of the machine room (use a lifting hook if the limiter is heavy: ~15kg).

• Mount the New Limiter: Align the new TAB20602K4 with the bracket’s bolt holes and secure it with the original bolts—tighten to 25 N·m using the torque wrench (over-tightening may distort the housing).

• Reconnect Electrical Wires: Match the labeled wires to the new limiter’s switches (refer to Nanjing Zhuye’s wiring diagram included with the product) and secure connections with wire nuts (prevent loose contacts).

• Reinstall the Safety Rope: Thread the safety rope into the limiter’s rope groove (follow the marked direction), reconnect the tension weight, and adjust rope tension (deflection ≤5mm as before).

• Safety System Test: Restore power to the elevator, enter maintenance mode, and perform the “overspeed simulation test” (using Otis’s test mode):

• • Confirm the pre-overspeed alarm activates at 105% of rated speed.

• • Verify the emergency stop and safety gear engagement at 115% of rated speed.

• Full Operation Test: Run the elevator through 5 full cycles (lowest to highest floor) to ensure smooth operation—no safety system false triggers.

• Documentation: Record the replacement date, test results, and maintenance personnel’s name (as required by elevator safety regulations). Troubleshoot: If false triggers occur, recheck rope tension or switch wiring; contact Nanjing Zhuye Elevator Parts’ 24/7 technical support for guidance.

• Normal Use (residential buildings, 8-12 hours daily operation, well-maintained machine room): Replacement cycle of 8 to 10 years.

• High-Intensity Use (commercial towers, airports, 18-24 hours daily operation, frequent start-stop cycles): Replacement cycle shortened to 5 to 7 years.

• Harsh Environments (machine rooms with high dust, humidity >70%, or temperature fluctuations >40°C): Replacement cycle of 4 to 6 years.

• Mechanical Wear: Rope groove depth reduced by >1.5mm (measured with a depth gauge) or gear train jamming (no smooth rotation).

• Switch Failure: Pre-overspeed alarm or emergency switch does not activate at specified speeds (even after adjustment).

• Structural Damage: Cracks in the cast iron housing, bent rope groove, or broken centrifugal components (pose safety risks).

• Regulatory Compliance: Some regions require mandatory replacement every 10 years (regardless of condition)—follow local elevator safety codes.

• Genuine Safety Compliance: Each TAB20602K4 is manufactured to Otis’s safety standards, with third-party certification (EN 81-20) to ensure it meets global safety requirements—avoiding risks from uncertified generic limiter.

• Quality Assurance: Uses the same materials as Otis’s original (cast iron housing, high-carbon steel gears) and includes a 3-year warranty (covers mechanical and electrical failures).

• Technical Support: Provides free on-site training (for bulk buyers) on speed limiter inspection and replacement, plus a detailed safety manual (with video tutorials) to reduce maintenance errors.

• Fast Emergency Delivery: For urgent replacements (e.g., failed limiter), Nanjing Zhuye offers 24-hour shipping to major markets (Europe, North America, Asia)—minimizing elevator downtime (critical for commercial buildings).