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Marvo Part ID: MV-2BNN

£78.26 (ex. VAT)

Pepperl + Fuchs

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Specification Description
Part Number Z728
Alternative Part Number Z728
Manufacturer Pepperl + Fuchs
Type Zener Barrier
Polarity DC version, positive polarity
Nominal Resistance Varies by model (240 Ω to 300 Ω)
Series Resistance Varies by model (max. 250 Ω to 341 Ω)
Fuse Rating Varies by model (50 mA to 80 mA)
Hazardous Area Connection Terminals 1, 2
Safe Area Connection Terminals 7, 8
Working Voltage Max. 26.9 V, 26.5 V at 10 µA
Degree of Protection IEC 60529
Ambient Temperature Range -20 ... 60 °C (-4 ... 140 °F)
Storage Temperature Range -25 ... 70 °C (-13 ... 158 °F)
Relative Humidity Max. 75%, without moisture condensation
Protection Degree IP20
Connection Screw terminals, max. core cross-section 2 x 2.5 mm²
Mass Approx. 150 g
Dimensions 12.5 x 115 x 110 mm (0.5 x 4.5 x 4.3 in)
Construction Type Modular terminal housing
Mounting On 35 mm DIN mounting rail acc. to EN 60715:2001
EC-Type Examination Certificate Varies by model (BAS 00 ATEX 7096, BAS 01 ATEX 7005, etc.)
Group, Category, Type of Protection Varies by model (e.g., ¬ II (1)GD, I (M1) [Ex ia] IIC, etc.)
Voltage Uo 28 V
Current Io Varies by model (93 mA to 120 mA)
Power Po Varies by model (650 mW to 830 mW)
Maximum Safe Voltage Um 250 V
Series Resistance (min.) Varies by model (min. 235 Ω to 301 Ω)
International Approvals FM, UL, CSA, IECEx approvals
Directive Conformity Directive 94/9/EC, EN 60079-0:2012, EN 60079-11:2012, EN 60079-15:2010, etc.

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Z728 Product Description

The Pepperl + Fuchs Z728 Zener Barrier is a vital component designed to ensure the safety and integrity of electrical systems in hazardous areas. This one-channel, DC version with positive polarity is engineered to prevent the transfer of excessive energy from safe areas into explosive environments, thereby mitigating the risk of ignition and ensuring operational safety. With a working voltage of 26.5 V at 10 µA and a maximum series resistance of 327 Ω, the Z728 is built to maintain a controlled environment for your electrical connections.

The Zener Barrier's robust design includes a nominal resistance of 300 Ω and a fuse rating of 50 mA, which together provide a reliable safeguard against electrical surges. The device is designed for easy mounting on a 35 mm DIN rail, in accordance with DIN EN 60715, making it a convenient and space-saving solution for panel installations.

Constructed with a modular terminal housing, the Z728 offers a degree of protection compliant with IEC 60529 standards, ensuring durability and longevity in a variety of industrial settings. The ambient operating temperature range of -20 to 60 °C and storage temperature range of -25 to 70 °C make it suitable for challenging environmental conditions.

The Zener Barrier is an essential component for industries operating in potentially explosive atmospheres, providing a high level of protection and peace of mind. Its meticulous design and construction make it a reliable choice for safeguarding your electrical systems against hazardous energy transfers.

Frequently Asked Questions

What is the function of a Zener Barrier?

A Zener Barrier is designed to limit the energy that can be transferred from a safe area to a hazardous area, thereby preventing the ignition of flammable gases or dust in the hazardous area. It achieves this by using Zener diodes to clamp the voltage and a fuse to disconnect the circuit in the event of an overvoltage.

Can the Zener Barrier be used in explosive atmospheres?

Yes, the Zener Barrier is suitable for use in potentially explosive atmospheres and is certified with ATEX and IECEx approvals, making it appropriate for Zones 0, 1, and 2 for gas and dust hazards.

What are the electrical specifications of this Zener Barrier?

The Zener Barrier has a nominal resistance of 240 to 300 ohms, a series resistance of up to 341 ohms, and a fuse rating of 50 to 80 mA. It is designed to work with a voltage of 26.5 V at 10 µA leakage current.

How is the Zener Barrier mounted?

The Zener Barrier is designed for mounting on a 35 mm DIN rail according to EN 60715:2001, which allows for easy installation and maintenance in control panels and equipment racks.

What are the ambient operating conditions for the Zener Barrier?

The Zener Barrier can operate in ambient temperatures ranging from -20 to 60 °C (-4 to 140 °F) and should be stored in temperatures from -25 to 70 °C (-13 to 158 °F). It is designed to function at a relative humidity of up to 75%, without moisture condensation.

What type of connections does the Zener Barrier support?

The Zener Barrier supports screw terminal connections with a maximum core cross-section of 2 x 2.5 mm², allowing for secure and reliable wiring to both the hazardous and safe area terminals.

What is the degree of protection provided by the Zener Barrier?

The Zener Barrier provides a degree of protection of IP20, which means it is protected against solid objects larger than 12.5 mm but is not protected against water ingress.

Is there any special certification for the Zener Barrier?

Yes, the Zener Barrier comes with EC-Type Examination Certificates and complies with various directives and standards such as EN 60079-0:2012, EN 60079-11:2012, and EN 60079-15:2010, ensuring its suitability for use in hazardous areas.

What are the dimensions and weight of the Zener Barrier?

The Zener Barrier has dimensions of approximately 12.5 x 115 x 110 mm (0.5 x 4.5 x 4.3 in) and weighs around 150 grams, making it compact and lightweight for its function.

Does the Zener Barrier have any replaceable components?

Some versions of the Zener Barrier come with a replaceable fuse feature, which allows for easy maintenance and replacement in case of a fault without the need to replace the entire unit.