LXLZ Note: This Product Provides Solutions for Parameter Customization And Application.
3-Phase 3-Wire EMI Filter Bolt Terminal 380V 440V
If you’re running industrial equipment — VFDs, servo drives, CNC machines, or any heavy three-phase load — you already know how much electromagnetic noise can wreck your system. Unexpected shutdowns, corrupted signals, damaged components. It’s a real headache. That’s exactly the problem this filter is built to solve.
The LZLX CW12B-S Series 3-Phase 3-Wire EMI Filter is a purpose-built power line filter for demanding industrial environments. With bolt-terminal connections on both the LINE and LOAD sides, it’s designed for panel builders and equipment manufacturers who need a reliable, easy-to-wire solution that actually holds up over years of operation.
We manufacture these directly at our Shenzhen facility — no middlemen, consistent quality, and full support for OEM/ODM orders.
Table of Contents
What You Can See from the Unit
From the product itself, a few things stand out right away:
- Stainless steel enclosure — not painted sheet metal. This tells you it’s built for longevity in humid or corrosive environments.
- Bolt-type terminals (both sides) — clearly labeled LINE (L1, L2, L3, E) and LOAD (L1′, L2′, L3′, D), which makes wiring straightforward even in tight panels.
- Onboard circuit diagram printed on the label — practical for field engineers who need to verify configuration without hunting for a datasheet.
- CE and RoHS marked — already certified for European market entry.
- Compact, flat-mount form factor — easy to integrate into standard electrical enclosures or control cabinets.
Key Specifications
| Parameter | Details |
|---|---|
| Model | CW12B-S Series (e.g. CW12B-30A-S) |
| Configuration | 3-Phase, 3-Wire |
| Rated Voltage | 380V / 440V AC |
| Rated Current | 1A – 40A (multiple ratings available) |
| Frequency | 50 / 60 Hz |
| Operating Temperature | -25°C to +85°C |
| Connection Type | Bolt Terminal (Stud Type) |
| Certifications | CE, RoHS |
| Enclosure | Stainless Steel |
| Function | EMI / RFI Suppression, Common Mode & Differential Mode Noise Filtering |
Note: Current ratings from 1A to 40A are available. Contact us with your load requirements and we’ll confirm the right spec for your application.
Typical Applications
This filter fits naturally into a range of industrial setups:
- Variable Frequency Drives (VFDs) — One of the most common uses. VFDs are notoriously noisy on the input side. This filter cleans up conducted interference before it reaches your upstream equipment or utility connection.
- CNC Machining Centers — Precision machinery needs clean power. Noise on the line causes positioning errors and control board failures.
- Servo Drive Systems — High-frequency switching in servo amplifiers generates EMI that needs to be contained.
- Industrial Automation Panels — Panel builders use these as standard components before PLCs, HMIs, and motion controllers.
- Welding Equipment — High-current, high-noise environment. The filter protects other equipment sharing the same supply.
- Medical & Lab Equipment Power Systems — Where power quality directly affects measurement accuracy.
- Elevator & Escalator Control Systems — Long cable runs make these systems especially vulnerable to conducted noise.
Why Bolt Terminals — And Why It Matters
A lot of cheaper EMI filters use screw-cage or quick-connect terminals. Under vibration or thermal cycling, those connections can loosen over time. Bolt terminals give you a mechanically secure, high-current-capacity connection that won’t back out. For industrial use — especially on anything above 20A — it’s the right choice. It also makes it easier to use ring terminals and properly torque connections to spec, which matters in UL/CE-compliant panel builds.
Manufacturing Advantages (Why Buy Direct from Us)
- Factory direct pricing — We are the manufacturer, not a trading company. Your per-unit cost reflects that.
- Consistent production quality — Same components, same process, every batch. We’re not sourcing from different sub-suppliers per order.
- OEM/ODM available — Custom current ratings, custom labels, custom packaging. Common for equipment manufacturers who want their own branding.
- Low MOQ for sampling — We understand you need to test before committing to volume. Sample orders are supported.
- Wide current range on one platform — 1A to 40A within the same CW12B-S family means one qualified supplier covers most of your project needs.
- CE + RoHS certified — Ready for export to EU, and generally accepted in most international markets.
Best Practices from the Field
Based on real installation experience with this type of filter:
1. Keep wiring short on both sides.
The filter works best when the LINE-side cable and LOAD-side cable are kept as short as practical and routed separately. Running them bundled together defeats the purpose — noise couples right back across.
2. Ground it properly.
The enclosure ground and the G/E terminal both need solid connections. A floating or high-impedance ground reduces common-mode attenuation significantly. Use a dedicated ground bar in the panel if possible.
3. Mount it close to the equipment input.
For VFDs especially, mount the filter right at the drive’s input terminals. The longer the unfiltered cable between filter and drive, the more it acts as an antenna.
4. Match the current rating conservatively.
Don’t run a 30A filter at 30A continuously if you can help it. Sizing up one step gives you thermal margin, especially in warm enclosures where ambient can push 40–50°C.
5. For CE compliance on your finished machine:
If you’re building equipment for EU export, combining this filter with proper shielded cable on the motor side gives you the best chance of passing conducted emissions on the first try. Many of our customers report this combination gets them through EN 61800-3 Category C2 without additional mitigation.
FAQ — What B2B Buyers Actually Ask
Can this filter handle both 380V and 440V systems?
Yes. The CW12B-S series is rated for up to 440V AC, which covers standard 380V (China/EU) and 440V (common in US industrial and some Asian markets) three-phase systems. It also handles both 50Hz and 60Hz, so one SKU works globally.
What’s the difference between your 3-wire and 3+N (4-wire) filters?
A 3-phase 3-wire filter (this product) is used in delta systems or systems where the neutral is not distributed — common in motor drive applications. If your system has a neutral line running to the load (typical in 3-phase+N distribution panels), you’d need a 4-wire version. If you’re unsure, send us your wiring diagram and we’ll advise.
Do you offer OEM labeling or custom current ratings?
Yes, both. We regularly produce custom-labeled units for equipment manufacturers who want their own brand on the filter. Custom current ratings within the CW12B platform are also available for volume orders. Lead time and MOQ depend on the specification — get in touch and we’ll give you a straight answer.
What certifications does this filter carry, and is it suitable for EU market equipment?
The filter carries CE and RoHS certification. For equipment being sold into the EU, this satisfies the Low Voltage Directive and EMC Directive requirements at the component level. Your finished machine will still need system-level CE marking, but using certified components like this is a necessary part of that process.
What’s your lead time and minimum order quantity?
Standard current ratings (10A, 20A, 30A) are typically in stock or available within 3–5 business days for sample quantities. Production orders are generally 2–3 weeks depending on volume. MOQ for standard models is flexible — we work with both small OEM runs and large procurement orders. Contact us with your quantities and timeline.
Ready to discuss your project requirements? Send us your application details — voltage, current, equipment type — and we’ll respond with the right specification and a factory price within 24 hours.