Camtec ESB00323 32A Series 3-Phase Inrush Current Limiter

High-current 3-phase installations — machine building, industrial automation, large-scale LED systems — face inrush current exposure on every phase simultaneously. A single weak link trips the circuit breaker and takes down the whole circuit. The Camtec ESB00323 limits inrush on all three phases independently, so no single phase event cascades into a system fault.

A 3rd-generation industrial-grade 3-phase inrush current limiter rated at 32A continuous (68.6A peak, 48A RMS), the ESB00323 operates on 200/400/500Vac three-phase networks without requiring a neutral conductor — PE connection is mandatory. Each AC line is monitored and limited independently via an integrated phase controller. Limiting is precise to ±6% every cycle — no NTC thermistor degradation over time.

An integrated phase controller provides relay signal outputs for phase loss, phase sequence error, and asymmetry/overvoltage/undervoltage faults, enabling integration with building management systems, PLCs, and SCADA. The limiting time (Ton: 70–240ms) and release time (Toff: 65–170ms) are user-adjustable via onboard potentiometers — factory settings are 150ms and 100ms respectively. Maximum capacitive load is 2,000µF.

Two variants are available: ESB00323A supports 200Vac, 400Vac, and 500Vac networks via an onboard voltage selector switch; ESB00323B supports 200Vac and 400Vac. The largest permitted upstream MCB is 32A. The ESB00323 is designed for capacitive loads only and is not suitable for use with transformers, AC motors, heaters, or DC voltage applications.

Housed in a robust aluminium IP20 enclosure (95×155×122mm, 1.1kg) on DIN-Rail TS35mm. Spring-type terminals accept up to 16mm² / 8AWG. Rated to IEC/EN62368-1, IEC/EN61010-1, IEC/EN61010-2-201, IEC/EN60950-1, and IEC/EN60204-1. EN55032 Class B EMI compliance. MTBF: 377,000h (IEC/EN61709). Operating temperature: −40°C to +70°C (ESB00323B) or +55°C (ESB00323A).