Bolt Terminal EMI Filter Single Phase High Current RFI

The CW4L2-S Series Single Phase AC Power Line EMI Filter represents the stud-terminal variant of the CW4L2 product family — engineered specifically for applications where high-current wire termination reliability, vibration resistance, and environmental robustness are the primary installation requirements.

Manufactured by LXLZ (Shenzhen Lize Electronics), the CW4L2-S replaces the conventional terminal block connection with stainless steel bolt-type stud terminals equipped with spring washers and flat washers — delivering a mechanically secure, low-resistance wire connection that withstands sustained vibration, thermal cycling, and high-current load conditions that would challenge standard screw-clamp terminal blocks.

The filter employs a proven dual-stage π-type LC filter circuit within a fully enclosed nickel-plated steel housing, providing effective suppression of both common-mode and differential-mode conducted EMI across industrial AC power lines rated at 115VAC and 250VAC, with current coverage from 1A to 20A at 50Hz / 60Hz.

All units carry CE and RoHS certification and are 100% electrically tested prior to shipment.

Specifications

📄 Full dimensional drawings, insertion loss curves, and test reports available upon request.

The S Series Difference — Stud Bolt Terminal Design

The defining characteristic of the CW4L2-S series is its stud-type bolt terminal connection system — a fundamentally different wire termination approach compared to the screw-clamp terminal blocks used in the CW4L2-R and CW4L2-RG series.

Terminal Construction Detail

Each terminal stud consists of:

• M4 Stainless Steel Threaded Stud — corrosion-resistant, high tensile strength
• Spring (Lock) Washer — maintains clamping force under vibration and thermal expansion cycles, preventing connection loosening over time
• Flat Washer — distributes clamping load across the wire lug or ring terminal contact surface
• Black Rubber Sealing Grommet — provides environmental sealing at the housing penetration point, protecting internal components from dust, moisture, and contaminants

Why Stud Terminals for Demanding Environments

The stud terminal design is the preferred connection method in marine, heavy industrial, transportation, and high-vibration environments where terminal block connections may loosen over time.

Circuit & Internal Component Details

Capacitor Network

• CX (X-Class, Differential-Mode): 3 × 0.1μF Line-to-line connected, suppressing differential-mode conducted noise from switching power supplies, inverter drives, and non-linear loads
• CY (Y-Class, Common-Mode): 2 × 3300pF Line-to-earth and neutral-to-earth connected, providing a controlled low-impedance discharge path to chassis ground for common-mode interference currents

Inductor Network

• L: 4 × 0.5mH Common-Mode Choke High-permeability toroidal core winding presenting high impedance to common-mode interference frequencies while maintaining minimal impedance at the 50/60Hz fundamental — ensuring negligible voltage drop and power dissipation under full rated load

Bleed Resistor

• R: 1MΩ / 0.5W X-capacitor discharge resistor ensuring safe dissipation of stored capacitor charge within the required time window after AC power disconnection — mandatory for compliance with IEC 60335, EN 60950, and related safety standards

Product Features

Fully Enclosed Nickel-Plated Steel Housing

The seamless, fully enclosed nickel-plated steel body provides:

• Maximum electromagnetic shielding effectiveness — no aperture leakage paths
• Superior protection against corrosion, humidity, and industrial chemical exposure
• Reliable chassis ground bonding contact surface
• Robust mechanical integrity for harsh environment installation

M4 Stainless Steel Stud Bolt Terminals

• Six stud terminals total — three on the LINE input side (L, N, E), two on the LOAD output side (L, N), plus chassis ground
• Stainless steel construction eliminates corrosion risk in humid or chemically active environments
• Spring washer retention maintains consistent clamping torque under repeated thermal cycling and mechanical vibration — critical for long-term connection integrity in industrial machinery
• Compatible with ring-type and fork-type wire lugs — enabling use with large-gauge cables beyond the capacity of standard terminal blocks

Rubber Sealing Grommets at Each Terminal

Individual black rubber grommets at each terminal penetration point:

• Prevent ingress of dust, moisture, and contaminants into the filter housing
• Provide mechanical strain relief at the cable entry points
• Contribute to the overall environmental protection rating of the assembly

Dual Voltage Rating: 115VAC / 250VAC

A single stocked variant supports both 115V/60Hz (North America) and 220–250V/50Hz (international) power systems — simplifying global OEM programs and international distribution inventory

Panel Mount Flanges with Secure Screw Fixing

Bottom-mounted fixing flanges with pre-drilled screw holes allow secure bolted installation onto equipment chassis, panel backplates, and structural mounting surfaces — providing a rigid, vibration-resistant installation foundation that complements the stud terminal connection system

Applications

The CW4L2-S Stud Terminal Series is specifically selected for environments and equipment types where vibration resistance, high-current wire termination, and environmental robustness are critical:

Heavy Industrial Machinery

• CNC heavy-duty machining centers and grinding machines
• Industrial press and stamping equipment
• Compressor and pump motor drive systems
• High-power welding and cutting equipment power conditioning

Marine & Offshore Equipment

• Vessel electrical panel power line filtering
• Offshore platform control and instrumentation panels
• Marine navigation and communication system power conditioning

Transportation & Automotive

• Railway on-board power systems and traction control
• Commercial vehicle auxiliary power unit filtering
• EV charging infrastructure input filtering
• Airport ground support equipment

Renewable Energy & Power Generation

• Solar inverter AC output and grid interface filtering
• Wind turbine nacelle control panel power conditioning
• Diesel generator set output harmonic and EMI filtering
• Battery energy storage system (BESS) interface filtering

Industrial Automation & Robotics

• High-power servo and spindle drive systems
• Industrial robot controller power input
• Automated welding and material processing systems

Power Electronics

• High-current industrial switching power supplies
• Large UPS system input filtering
• Industrial DC power supply AC input stages

Test & Measurement Infrastructure

• High-power test bench power conditioning
• EMC test facility power line filtering