Ex plugs and sockets are specialized electrical connection devices designed for use in hazardous areas where flammable gases, vapours, dust or combustible materials may be present. These explosion-proof plugs and sockets provide a secure method of connecting portable equipment, machinery and local power supplies while helping reduce the risk of ignition in potentially explosive atmospheres.
The CZ025 series from CZ Electrical is a range of full-plastic explosion-proof plugs and sockets designed for hazardous areas classified as Zone 1, Zone 2, Zone 21 and Zone 22. Depending on the model, the series is available in ratings from 16 A to 125 A, with different pole configurations, voltage options and connection types.
What Are Ex Plugs and Sockets?
Ex plugs and sockets are specialized electrical connection systems designed for hazardous areas where explosive gases, vapours or combustible dust may be present. They are used for safely connecting portable tools, pumps, lighting equipment, motors, mobile machinery and temporary power systems in industries such as oil and gas, petrochemical, chemical processing and manufacturing.
The correct Ex plug and socket should be selected based on the hazardous-area classification, voltage, current rating, number of poles, protection method and applicable certification.
Ex Plugs and Sockets for Hazardous Area Zones
Hazardous areas are classified according to the likelihood and duration of the presence of an explosive atmosphere.
Zone 1
Zone 1 areas are locations where an explosive gas, vapour or mist atmosphere is likely to occur during normal operation occasionally.
Zone 2
Zone 2 areas are locations where an explosive gas, vapour or mist atmosphere is not likely to occur during normal operation but, if it does occur, will exist only for a short period.
Zone 21
Zone 21 refers to areas where a combustible dust cloud is likely to occur occasionally during normal operation.
Zone 22
Zone 22 refers to areas where a combustible dust cloud is not likely to occur during normal operation but may occur for a short period.
CZ Electrical CZ025 Ex Plug and Socket Series
The CZ025 series from CZ Electrical is a full-plastic range of explosion-proof plugs and sockets designed for hazardous-area electrical connections.
The series covers current ratings from 16 A to 125 A and is available in different configurations, including wall-type sockets, panel-type sockets, couplers and plugs, depending on the model.
The CZ025 series can be used in Zone 1, Zone 2, Zone 21 and Zone 22 applications, subject to the certification and configuration of the specific product.
The selected Ex plug and socket must have the appropriate certification and protection concept for the intended hazardous area.
Key Features of the CZ025 Series
Full-Plastic Anti-Static Enclosure
The CZ025 series uses an anti-static alloy plastic / GRP (glass-fibre-reinforced polyester SMC) enclosure. This provides a robust solution for demanding industrial and hazardous-area applications.
Interlocked Design
The interlocking mechanism helps prevent the plug from being disconnected while the switch is energised. It also helps prevent the equipment from being switched on before the plug is correctly engaged.
Protective Covers
Protective covers help protect connections against dust and moisture ingress. Wall-type sockets also include a provision for padlocking.
Self-Cleaning Contacts
The contact design provides multiple contact points to support reliable electrical connection and help maintain low contact resistance.
Wide Temperature Range
Depending on the model and Ex classification, selected CZ025 configurations can operate in ambient temperatures from −40°C to +55°C.
International Certifications
Applicable CZ025 models are available with IECEx, ATEX, ECAS and China CCC certifications.
CZ025 Product Range
| Model | Rated Current | Poles | Main Configurations |
|---|---|---|---|
| CZ0251 | 16 A | 2, 3, 4, 5 | Wall socket, panel socket, coupler and plug |
| CZ0252 | 32 A | 4, 5 | Wall socket, panel socket, coupler and plug |
| CZ0253 | 63 A | 4, 5 | Wall socket and plug |
| CZ0254 | 125 A | 4, 5 | Wall socket and plug |
CZ025 Model Details
CZ0251 – 16 A Ex Plugs and Sockets
The CZ0251 is the 16 A model in the CZ025 range and is available in 2-, 3-, 4- and 5-pole configurations.
It is suitable for applications such as:
- Hand tools
- Portable lighting
- Instrument power
- Small pumps
- Low-voltage power supplies
- Portable electrical equipment
The wall-type socket uses an M25 × 1.5 cable entry for cable diameters of 9–17 mm.
Plug and coupler configurations accept:
- Ø6.5–18.5 mm cables for 2P and 3P versions
- Ø6.5–20 mm cables for 4P and 5P versions
The CZ0251 is available with protection ratings of IP66 for panel sockets, plugs and couplers and IP65 for wall sockets.
Depending on the configuration, rated voltages include 50 V AC/DC for 2P, up to 250 V AC for 3P, up to 690 V AC for 4P and up to 415 V AC for 5P.
CZ0252 – 32 A Ex Plugs and Sockets
The CZ0252 is the 32 A model, available in 4- and 5-pole configurations.
It is suitable for heavier portable and mobile equipment, including:
- Welding equipment
- Portable pumps
- Mixers
- Blowers
- Mobile machinery
The wall-type socket uses an M32 × 1.5 cable entry for Ø13–21 mm cables.
Plug and coupler versions accept cables from Ø10–28 mm.
The CZ0252 provides up to 690 V AC for 4-pole versions and up to 415 V AC for 5-pole versions, depending on the selected configuration.
CZ0253 – 63 A Ex Plugs and Sockets
The CZ0253 is a 63 A heavy-duty model designed for higher-power applications.
Typical applications include:
- Large pumps
- Compressors
- Mobile generators
- Heavy-duty machinery
- Temporary power distribution
The wall-type socket uses an M50 × 1.5 cable entry for Ø22–35 mm cables, while the plug accepts cables from Ø15–35 mm.
The CZ0253 is available in 4- and 5-pole configurations, with maximum rated voltages of 690 V AC for 4P and 415 V AC for 5P, depending on the configuration.
CZ0254 – 125 A Ex Plugs and Sockets
The CZ0254 is the highest-current model in the CZ025 series, with a rated current of 125 A.
It is available in 4-pole and 5-pole configurations as a plug and wall-type socket. The model is intended for heavy-duty electrical power connections and temporary distribution applications.
The CZ0254 incorporates an interlocked switch design. Exact electrical ratings, protection levels, cable entries, dimensions and certification details should be confirmed against the latest manufacturer documentation for the selected configuration.
Ex Protection and Certification
Certification is an important consideration when selecting an Ex plug and socket for hazardous areas.
Applicable CZ025 models can carry certifications including:
- IECEx
- ATEX
- China CCC
Depending on the model and configuration, Ex markings can include: Ex db eb IIC T6 Gb and Ex tb IIIC T80°C Db
Other temperature classifications, such as T5 / T95°C, are available for certain configurations and ambient-temperature conditions.
The exact Ex marking and certification should always be checked against the product's specific certificate and datasheet before installation.
Voltage Coding and Clock Positions
The CZ025 series uses clock-position coding to help prevent incompatible plugs and sockets from being connected.
Different voltage configurations use different earth-pin positions and keyways. This provides mechanical differentiation between voltage ratings and helps prevent incorrect connections.
| Voltage | Poles | Clock Position |
|---|---|---|
| 20–25 V AC | 2P, 3P | – |
| 40–50 V AC | 2P, 3P | 12h |
| 20–50 V DC | 2P | 10h |
| 110–130 V AC | 3P | 4h |
| 200–250 V AC | 3P | 6h |
| 200–250 V | 4P | 9h |
| 380–415 V | 4P | 6h |
| 380–440 V | 4P | 3h |
| 480–500 V | 4P | 7h |
| 600–690 V | 4P | 5h |
| 200–250 V / 380–415 V | 5P | 6h |
How to Select an Ex Plug and Socket
Choosing the correct Ex plug and socket requires more than simply matching the current rating.
Consider the following factors:
1. Hazardous Area Classification
Confirm whether the installation is in Zone 1, Zone 2, Zone 21 or Zone 22.
2. Rated Current
Select a plug and socket according to the equipment's required current.
- Up to 16 A – CZ0251
- Up to 32 A – CZ0252
- Up to 63 A – CZ0253
- Up to 125 A – CZ0254
3. Voltage
Confirm the required operating voltage and corresponding clock position.
4. Number of Poles
Select the appropriate 2-, 3-, 4- or 5-pole configuration according to the electrical system.
5. Cable Diameter
Make sure the cable diameter falls within the permitted range of the selected plug, socket or cable entry.
6. Protection Rating
Check the required IP rating based on the installation environment and equipment configuration.
7. Certification
Confirm that the product's IECEx, ATEX or other applicable certification is suitable for the hazardous area and installation requirements.
Installation and Safety Considerations
Ex plugs and sockets should be installed by suitably qualified personnel and in accordance with the manufacturer's installation instructions and applicable hazardous-area standards.
Important considerations include:
- Isolate the electrical circuit before installation.
- Verify that the work area is safe.
- Use the correct cable and compatible accessories.
- Ensure cable entries and connections are correctly assembled.
- Maintain proper protective earthing.
- Install certified stopping plugs in unused entries.
- Check the plug and socket for damage before use.
- Follow the specified tightening requirements.
- Inspect the completed installation before energising.
- Maintain installation records where required.
For hazardous-area installations, applicable requirements such as IEC 60079-14 and IEC 60079-17 should be considered alongside the manufacturer's instructions.
Which CZ025 Model Should You Choose?
| Requirement | Recommended Model | Main Advantage |
|---|---|---|
| Hand tools, lighting and instruments | CZ0251 – 16 A | Compact 16 A solution with multiple pole options |
| Portable three-phase equipment up to 32 A | CZ0252 – 32 A | Higher current capacity with wall, panel, coupler and plug options |
| Large pumps and compressors | CZ0253 – 63 A | Heavy-duty 63 A configuration |
| Heavy-duty power and temporary distribution | CZ0254 – 125 A | Highest current rating in the CZ025 series |
| Panel installation | CZ0251 / CZ0252 panel type | Designed for panel mounting |
| Equipment extension connections | CZ0251 / CZ0252 coupler type | Suitable for portable connection arrangements |
Ex Plugs and Sockets Supplier in Abu Dhabi, UAE
Power Electrical Trading LLC supplies Ex plugs and sockets for hazardous-area applications in Abu Dhabi and across the UAE. We offer explosion-proof electrical solutions suitable for Zone 1, Zone 2, Zone 21 and Zone 22, including the CZ (Chuangzheng) CZ025 series of full-plastic Ex plugs and sockets.
These products are suitable for oil and gas, petrochemical, chemical and other industrial applications requiring reliable electrical connections in potentially explosive environments.
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