<![CDATA[
Overview
The Telemecanique LA4DFB interface module is a solid-state relay amplifier engineered for seamless integration with Schneider Electric TeSys D series contactors. This module solves the common automation challenge of switching high-power contactors using low-level signals from PLC outputs. With its compact top-mount design and direct terminal connection, the LA4DFB provides electrical isolation and reliable switching without external wiring harnesses or adaptor cards.
Key Features
- Low-Level PLC Signal Input: Accepts signals as low as <2mA from PLC outputs, eliminating the need for additional relay logic.
- Dual Voltage Rated: 24VDC control input with 250VAC switching capability across three poles.
- Direct Terminal Mounting: Mounts directly onto contactor coil terminals; no auxiliary wiring required.
- Solid-State Isolation: Provides electrical isolation between PLC control circuits and power contactors.
- TeSys D Compatibility: Tested and rated for contactors up to 80kW; smaller units (4–18.5kW) may require optional coil adaptor.
Technical Specifications
- Control Input Voltage: 24VDC
- Output Rating: 250VAC/250VDC
- Number of Poles: 3
- Input Signal Level: <2mA (PLC compatible)
- Mounting Type: Direct terminal mount (top of contactor)
- Weight: 0.20 lbs (90g)
- Operating Temperature: Industrial grade (refer to technical documentation)
- Compliance: IEC 255-5, VDE 0110-C, RoHS compliant
- Isolation Type: Solid-state (no moving contacts)
- Current Rating (Input): <2mA
Typical Applications
The LA4DFB is widely used in:
- HVAC systems where PLC outputs drive large contactor coils.
- Motor soft-starters and pump control panels.
- Industrial machinery automation requiring safe switching of 3-phase loads.
- Retrofit installations where legacy PLC systems lack sufficient relay drive capacity.
- Data center and telecom equipment racks with remote start/stop logic.
Compatibility & Replacements
Compatible With
- Schneider Electric TeSys D series contactors (LC1D09–D150)
- 24VDC PLC outputs and programmable controllers
- IEC 60947-4-1 compliant contactor systems
- HVAC and industrial motor control circuits
- Systems requiring low-current switching logic
Replaces / Drop-In Replacement For
Verify compatibility with your system integrator before ordering. The LA4DFB is a TeSys D-specific interface; compatibility with legacy Telemecanique models or other manufacturers’ contactors is not guaranteed without verification.
Works With
- Standard industrial PLC platforms (Allen-Bradley CompactLogix, Siemens S7-1200, Mitsubishi FX, Omron CP, etc.)
- Standard 24VDC control power supplies
- IEC-standard contactor terminals and coil connectors
- Hardwired relay logic and soft-start controllers
]]>












