Vitreous Enamelled Wirewound Resistors – WZO Series

Category: Electronics, Resistors, TT Electronics PLC

Product Overview: The WZO Series encapsulates a range of high-performance vitreous enamelled wirewound resistors designed for demanding applications that require high reliability and stability. This series of resistors, manufactured by TT Electronics, is particularly suited to harsh environments due to their robust construction and overload characteristics.

Key Features:

CECC approved design, ensuring that these resistors meet or exceed stringent requirements.
Constructed with a high purity ceramic substrate and fitted with interference fit end caps, these resistors exhibit high structural integrity.
Terminations are made from copper-clad steel wire which is nickel-plated and solder-coated, providing excellent solderability and strength compliant with IEC standards.

Performance and Reliability:

The WZO Series resistors demonstrate high stability and reliability with overload protection features, making them ideal for use in protective circuits.
When exposed to high temperatures, the vitreous enamel coating maintains excellent insulation resistance, although care should be taken with proximity to conducting materials.
Resistance values range widely, from 0.1 ohms up to 100K ohms, and the resistors have a low temperature coefficient of resistance (TCR) typically <+/-15 ppm/°C and maximum +/-200 ppm/°C across the various models.

Electrical and Physical Specifications:

Commercial power ratings range from 1W to 14W at 25°C, with operational temperature ranges from 55°C to 200°C.
A wide range of tolerance levels (1%, 2%, and 5%) is available for precision requirements.
Physical dimensions vary among resistor models within the series, making it feasible to find the correct size for specific applications. Minimum lead lengths and details about packaging dimensions are provided.
The series includes models like W21, W215, W22, W23, and W24, each differing in power ratings and dimensions.

Environmental Resistances:

The construction materials are inherently non-flammable and the coating offers resistance to industrial cleaning solvents suitable for printed circuits.

Applications and Handling:

This series is versatile, suitable for commercial and industry-approved ranges.
Special handling notes are included, emphasizing minimum bending radii and soldering clearance to maintain mechanical and electrical integrity.

General Notes:

TT Electronics holds the rights to change specifications without notice. Information is deemed accurate but is subject to their own data accuracy up until the publication date. The product datasheet has been released by TT Electronics plc and should be reviewed for detailed specifications.