Description

1. Part-number breakdown WECO-K2 = WECO light-curtain switch, 24 VDC, 16 inputs, 8 outputs, 2 × RS-485, IP20, –10 °C…+60 °C
   Outputs: 2 A per channel, short-circuit protected, 2 kV isolation
   MTBF: 90 kh @ 25 °C, MTTR <3 min (hot-swap)
2. Safety first—lock-out & verify The switch sits on the 24 VDC logic rail but switches 110 V curtain power. Lock the main disconnect, hang a lock-out tag and wait 60 s for the rail to fall below 5 V. Keep the new NYE switch in its anti-static bag until mounting—CMOS logic can latch at 15 V static.
3. Mechanical mounting—keep it cool Snap onto 35 mm DIN rail inside the car-top or landing box. Maintain 50 mm clearance above and below; every 10 °C rise halves relay life. If the box is <100 mm deep, mount vertically with RS-485 down—this allows convection chimney. NYE supplies a free DIN clip (NY-DIN-K2) and 10 mm thermal pad (NY-PAD-K2) for shallow enclosures.
4. Wiring map (print and stick inside box) 24 V & 0 V: 2.5 mm², 105 °C silicone, torque 0.8 N·m
   Inputs: 16 × dry contact, 1 mm², torque 0.5 N·m
   Outputs: 8 × 2 A, 1 mm², common anode, 24 VDC max
   RS-485-A/B: twisted pair, 120 Ω termination at last board (DIP-1 ON)
   Earth: 4 mm² green/yellow to box PE; logic leakage <1 mA
5. Power-up & self-test Apply 24 VDC; green “SYS” LED blinks 3 s, then steady.
   RS-485 link LED must light within 5 s; if flashing 1 Hz, address conflict—check DIP switches.
   Self-test: all outputs cycle, inputs toggle, curtain beam test 2 s. Any fail = red “FLT” LED + code on LCD.
6. Beam calibration & fault simulation Place 5 mm rod in centre of curtain; switch must report “BLOCK” within 50 ms.
   Remove rod; “CLEAR” must appear within 50 ms.
   If delay >100 ms, alignment is poor—re-align curtain heads or replace switch.
7. AI fault prediction (K2) On-board neural network analyses beam interruption pattern.
   Alarm threshold: 95 % confidence, 0.5 s latency.
   False-positive rate: <1 % on validated WECO curtains.
   If prediction >5 % after 30 days, re-train with NYE Cal Tool (free).
8. Temperature & lifetime model Relay contacts: 1 million cycles; at 600 door cycles/day = 4.5 years.
   Flash memory: 100 k erase cycles, 20 year retention @ 25 °C.
   Capacitor C1 (100 µF, 35 V): 2 000 h @ 105 °C, 64 kh @ 45 °C.
   Translate to building traffic: Light traffic (office, 600 cycles/day) – relays ≈ 4.5 years, flash ≈ 15 years, full switch ≈ 10 years; inspect every 3 years. Medium traffic (mall, 1 200 cycles/day) – relays ≈ 2 years, flash ≈ 8 years, full switch ≈ 5 years; inspect every 2 years. Heavy traffic (metro, 2 400 cycles/day) – relays ≈ 1 year, flash ≈ 4 years, full switch ≈ 3 years; inspect every 6 months.
9. Preventive inspection checklist Monthly: visual SYS LED, place rod, listen for relay click. Quarterly: measure 24 VDC ripple; >200 mV pp indicates supply fatigue. Annually: megger inputs to PE >100 MΩ; <10 MΩ indicates moisture ingress. Bi-annually: torque test 24 V screws; vibration loosens them, causing intermittent “E-K2”.
10. Rapid swap (downtime < 3 min) a) Power down, lock-out, wait 60 s.
    b) Photograph wire numbers with phone.
    c) Remove DIN clip, slide old switch out.
    d) Insert new NYE WECO-K2, snap onto rail.
    e) Restore wires in exact order, set DIP switches as photo.
    f) Power up, run beam test, verify 50 ms response.
    g) Log serial number and cycle counter; return old unit for recycling.
11. Recycling & sustainability Nanjing Zhuye offers prepaid UPS labels inside every carton.
    Returned switches are stripped: gold fingers go to certified refinery, plastic housing re-granulated, relay silver recovered.
    One recycled K2 saves 1.2 kg CO₂—enough to power the same curtain for a week.