Schneider Electric TeSys K Bidirectional Peak Limiting Diode Suppressor Module (LA4KC1B)
The Schneider Electric LA4KC1B is a high-performance, plug-in transient surge suppressor module designed explicitly for the TeSys K line of compact contactors and control relays. Utilizing an advanced bidirectional peak-limiting diode (TVS) topology, this safety module clips high-voltage transient spikes generated by the contactor coil when it is de-energized. By containing these inductive voltage transients to a safe maximum of 2 $U_c$, it protects fragile solid-state programmable logic controller (PLC) outputs, electronic drive cards, and sensitive automation circuitry from electrical noise and premature component degradation.
Key Features
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Bidirectional Peak-Limiting Diode Technology: Provides instantaneous symmetric clipping of inductive voltage transients in both positive and negative directions, making it ideal for clean, high-frequency switching lines.
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Seamless TeSys K Integration: Features a specialized snap-on front architecture that plugs directly onto compatible LC1K, LP1K, CA2K, and CA3K contactors/relays without requiring tools or taking up additional DIN-rail space.
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Precise Control Voltage Range: Engineered to operate efficiently across a nominal control circuit voltage envelope of 12 V to 24 V AC/DC, offering total versatility for low-voltage control setups.
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Minimal Electronic Delay: Delivers a very low switch-off time delay multiplication factor (approx. 1.1 to 1.5 times the normal contactor opening speed), ensuring that circuit interruption remains fast and crisp.
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Optimized Circuit Protection: Restricts transient peak voltages cleanly to a threshold of $2 \times U_c$ (twice the operational control voltage), absorbing back-EMF energy before it propagates onto the control bus.
Technical Specifications
| Feature | Specification |
| Model / Catalog Number | LA4KC1B |
| Brand / Product Range | Schneider Electric / TeSys K |
| Product Type | Suppressor Module / Transient Voltage Surge Suppressor (TVSS) |
| Suppressor Technology | Bidirectional Peak-Limiting Diode (Transient Voltage Suppressor) |
| Control Circuit Voltage ($U_c$) | 12 V to 24 V AC / DC (50/60 Hz for AC) |
| Maximum Peak Voltage | $2 \times U_c$ |
| Mounting Location | Front-mount clip-on interface |
| Product Compatibility | TeSys K Contactor Series (LC1K, LP1K) / Control Relays (CA2K, CA3K) |
| Net Weight | 0.010 kg (10 grams) |
| Standards & Certifications | UL Recognized, CSA Certified, UKCA, CE Marked, RoHS Compliant |
Applications
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PLC Interface Isolation: Suppressing back-EMF spikes directly at the contactor coil to shield digital PLC output transistor modules from voltage breakdown.
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Industrial Control Panels (ICPs): Reducing electromagnetic interference (EMI) inside compact control enclosures to guarantee the signal integrity of nearby analog loops and data pathways.
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HVAC Control Systems: Protecting localized electronic thermostat signals and auxiliary timing relays from inductive grid noise.
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Material Handling & Conveyors: Enhancing electrical system reliability in automated sorting lines where control relays cycle on and off continuously under heavy production runs.
