Schneider LC1D18M7 AC Contactor

Series: TeSys D (TeSys Deca), import model (without suffix-C)

Model Decoding

LC1D: TeSys D series 3-pole AC contactor

18: Rated operational current 18A under AC-3 utilization category

M: Coil voltage AC220V

7: Coil frequency 50/60Hz universal

LC1D18MC: Domestic-manufactured version; LC1D18M7: Overseas/imported version. Fully pin-to-pin compatible and interchangeable.

Core Electrical Specifications

Terminal Assignment

Main circuit: L1(1-1), L2(3-2), L3(5-3); T1(2-1), T2(4-2), T3(6-3)

Coil: A1, A2 → AC220V power supply

Auxiliary: 13-14 (NO Normally Open), 21-22 (NC Normally Closed)

Selection & Replacement

1. Direct compatible domestic equivalent: LC1D18M7C (Local production, identical footprint, current and coil rating, widely used in projects)
2. Coil voltage variants:

LC1D18B7: AC24V

LC1D18F7: AC110V

LC1D18Q7: AC380V

3. Domestic compatible alternatives: CJX2-1810 (1NO), CJX2-1801 (1NC), CJX2-1811 (1NO+1NC) matches the auxiliary-contact configuration of this model.

Typical Applications

Direct-on-line switching of 3-phase motors, fans, water pumps, compressors, HVAC systems, low-voltage switchgear, star-delta starters, conveyor belts; Standard AC-3 motor loads; Up to 32A for AC-1 resistive loads.

Troubleshooting & Maintenance Notes

1. Judge coil integrity by measuring resistance across A1-A2. Operating coil voltage shall remain within 0.8-1.1 × 220 V; Undervoltage causes chattering.
2. Auxiliary contacts rated max.5A, for control-signal circuits only. Do not switch power loads.
3. Tighten terminals to 1.7 N·m. Insufficient torque leads to overheating and burnt terminals.

Application Fields of Schneider LC1D18M7 AC Contactor

LC1D18M7 is a TeSys-D 3-pole 18A contactor, rated for 7.5 kW@400 V under AC-3 with AC220 V 50/60 Hz coil. It is widely deployed in industry, building services, HVAC and OEM equipment.

1. Industrial Machinery & Equipment

Direct start-stop control for 3-phase asynchronous motors: conveyor belts, mixers, grinders, small pumps, air compressors, ventilation fans.

Machine-tool equipment: Lathes, milling machines, packaging machinery, printing equipment for main-circuit switching.

Star-delta starting circuits, motor-reversing circuits. Can be paired with thermal overload relays for motor overload protection.

Automation control cabinets: PLC outputs drive contactor coils to switch high-power loads.

2. HVAC (Heating, Ventilation and Air-Conditioning)

Central air-conditioning units, cabinet fans, cooling-tower fans, circulating water pumps.

Fresh-air handling and exhaust systems, building electromechanical switch rooms.

AC220 V coil variants such as LC1D18M7 are extensively used in HVAC installations.

3. Building Services & Power Distribution

Factory power panels, compact low-voltage distribution cabinets.

Water supply & drainage: Sewage pumps, booster pumps, drain-pump control.

Centralised lighting control (Max.32 A AC-1 resistive), switching for high-power heating elements and resistive loads.

4. Lifting & Logistics Warehousing

Small hoisting mechanisms, conveyor systems, sorting equipment.

Not suitable for heavy jog-lifting duty cycles (Select higher-endurance contactors for frequent jogging).

5. OEM Complete-Set Equipment

Used as standard component by machinery manufacturers: food-processing machines, auxiliary injection-moulding equipment, environmental-protection and water-treatment systems.

Application Limitations (Unsuitable Scenarios)

1. Not intended for DC main-circuit switching (DC-type contactor required).
2. Avoid extremely frequent jogging / high-cycle operation, which drastically shortens electrical service life.
3. 1NO+1NC auxiliary contacts are limited to control-level signals (max.5 A). Never carry main power loads.

Common Matching Accessories

Overload protection: LRD series thermal overload relays

Auxiliary-contact expansion: LADN auxiliary contact blocks

Coil surge suppression: LADRC surge suppressors to reduce electromagnetic interference