What is the difference between CWDM and DWDM, and when should I choose CWDM?

CWDM (Coarse Wavelength Division Multiplexing) uses 20 nm channel spacing across 1270–1610 nm, supporting up to 18 channels. DWDM (Dense WDM) uses 0.8 nm or 0.4 nm spacing with narrowband lasers and temperature-controlled multiplexers, supporting 40+ channels. CWDM is the preferred choice for short- to medium-reach applications (< 80 km) where cost, power consumption, and operating temperature range are primary concerns. The MetalShield CWDM-18M is ideal for enterprise, industrial, and metro access networks.

How is the MetalShield CWDM-18M installed? Does it require special racking?

The module uses a standard LGX footprint (130 × 23 × 100 mm) and can be installed in any LGX-compatible chassis, including 19-inch rack-mount panels and wall-mount fiber distribution boxes. No special racking is required. Simply slide the module into an available LGX slot and secure with the retaining clip. LC fiber patch cords connect to the front-panel LC adapters.

Is the MetalShield CWDM-18M compatible with standard LGX rack chassis from other vendors?

Yes. The module complies with the standard LGX form factor and is compatible with LGX chassis from major fiber optic infrastructure vendors. The LC adapters are standard duplex LC, compatible with any standard LC patch cord. If you have a specific chassis model, contact Opelink technical support for compatibility confirmation.

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MetalShield CWDM-18CH | Industrial Metal Housing CWDM Module | 18-Channel MUX/DEMUX | Opelink

MetalShield CWDM-18CH | Industrial Metal Housing CWDM Module | 18-Channel MUX/DEMUX | Opelink

Name: MetalShield CWDM-18CH | Industrial Metal Housing CWDM Module | 18-Channel MUX/DEMUX | Opelink
Brand: OPELINK
SKU: Y-FO-WD-067
Availability: InStock
Rating: 5 (1 reviews)

Item No.: Y-FO-WD-067

The MetalShield CWDM-18CH is an 18-channel CWDM MUX/DEMUX bidirectional module housed in a rugged LGX metal enclosure, designed for harsh industrial and outdoor telecom environments.

INQUIRY

Description Parameters Company Profile Related Product

Product Overview

The MetalShield CWDM-18CH is engineered for mission-critical wavelength division multiplexing applications where environmental reliability is non-negotiable. Traditional CWDM modules housed in ABS plastic enclosures often degrade when exposed to wide temperature swings, high humidity, mechanical vibration, or electromagnetic interference—conditions common in industrial automation sites, 5G fronthaul deployments, and outdoor telecom cabinets.
Opelink's MetalShield series addresses these failure modes with a precision-machined metal housing that delivers three fundamental advantages: superior heat dissipation and effective EMI shielding. The metal enclosure acts as both a thermal reservoir and a Faraday cage, stabilizing internal component temperatures and blocking external electromagnetic noise that can degrade optical signal integrity.
The module supports the full ITU-T G.694.2 CWDM wavelength grid (1270 nm to 1610 nm, 20 nm spacing), providing 18 independent channels over a single fiber pair. This enables network operators to multiply existing fiber capacity by up to 18× without laying new cable, with MUX and DEMUX functions integrated into a single bidirectional LGX package.
Key differentiators of the MetalShield CWDM-18CH include:
.Metal housing thermal design: Metal enclosure with optimized surface area for passive heat dissipation, reducing internal component temperature by up to 12 °C compared to equivalent ABS plastic housings under the same load.
.EMI shielding performance: Metal enclosure provides >40 dB shielding effectiveness across 100 MHz–3 GHz, protecting sensitive optical components from industrial electromagnetic noise.
.Wide temperature operation: Qualified across –40 °C to +85 °C ambient with no performance degradation, exceeding the –5 °C to +70 °C range of standard plastic-housed modules.
.LGX form factor: Standard LGX footprint compatible with 19-inch rack-mount chassis and wall-mount panels, enabling seamless integration into existing fiber distribution frames.
Every unit is 100% optically tested and shipped with an individual test report, ensuring insertion loss, isolation, PDL, and return loss meet or exceed specifications.
MetalShield CWDM-18CH | Industrial Metal Housing CWDM Module | 18-Channel MUX/DEMUX | Opelink

Application Scenarios

1. Industrial Automation Networks

In smart manufacturing and process automation, fiber optic links must operate reliably in the presence of high-current motors, welding equipment, and electromagnetic noise. The MetalShield CWDM-18M provides EMI shielding and wide-temperature operation, enabling stable multi-channel communication between PLCs, HMIs, and remote I/O nodes over a single fiber pair in factory floor environments where ambient temperatures can exceed 60 °C.

2. 5G Base Station Fronthaul

5G fronthaul networks require CWDM solutions deployed in outdoor cabinets at cell sites, often exposed to temperature extremes, dust, and precipitation. The metal enclosure protects the optical MUX/DEMUX from environmental ingress, while the –40 °C to +85 °C operating range ensures year-round reliability without active cooling or heating, reducing site power and maintenance costs.

3. Outdoor Telecom Rooms / Street Cabinets

Street-level telecom distribution cabinets house active equipment in uncontrolled environments. The MetalShield CWDM-18M's metal housing dissipates heat generated by co-located active equipment. The module's vibration resistance ensures reliability in roadside installations subject to traffic-induced vibration.

4. Data Center Edge Nodes

Edge computing nodes are increasingly deployed in non-central-office locations such as enterprise premises and remote POPs. These environments lack the strict climate control of core data centers. The MetalShield CWDM-18M provides the temperature tolerance and EMI resilience needed for edge deployments, while the standard LGX form factor integrates cleanly into existing fiber patch panels.

5. Smart Grid Communication

Electrical substations and smart grid infrastructure require fiber optic communication that is immune to high-voltage electromagnetic interference and wide temperature variations. The MetalShield CWDM-18M's metal enclosure provides EMI shielding that protects optical signals from substation switching transients, while the wide operating temperature range ensures reliable operation in both desert and arctic grid installations.

Order Information:

Type	Upgrade Port	Port	Wavelength	Pigtail	Fiber	Length	Connector （Input-Output）	Package
M=Mux D=Demux M+D=Mux+ Demux	U= Yes 0= No	1002=1X2 1004=1X4 1008=1X8 1016=1X16 XX=other	27=1270 47=1470 49=1490 61=1610 Or 271=1271 471=1471 491=1491 611=1611	L=900um loose tube 2=2.0mm 3=3.0mm B= baare fiber A= Adaptor	S1=G652D S2=G657A1 X= other	0.5M=0.5M 1M=1.M X=other	SU=SC/UPC SA=SC/APC FU=FC/UPC FA=FC/APC ST=ST/UPC LA=LC/APC LU=LC/UPC 00=NONE XX= other	01,02,03,04,05 H,L,U,G,X

Optical Specifications:

Parameter		Value
Channels Number		2	4	8	16	18
Central Wavelength（nm）		ITU-T Grid
Bandwidth(@0.5dB Pass band)（nm）		ITU-T ±6.5
Channel Pass band（nm）		20
I.L（dB）	Typ.	1.2	1.6	2.2	3.2	3.8
	MAX.	1.4	1.8	2.8	5.0	5.6
Ripple（dB）		≤0.3
PDL（dB）		≤0.10	≤0.15	≤0.20	≤0.25	≤0.30
Isolation（dB）	Adjacent Channel	≥30
	Non-adjacent Channel	≥45
Directivity（dB）		≥50
R.L（dB）		≥45
Operating Temperature（℃）		-5~+75
Storage Temperature（℃）		-40~85
Note: All the data above does not include connectors

Review

Sady

Jun 03, 2026

Each one comes with a test report, very good