Theory of Operation 4

Introduction

Introduction

4-1.

This section presents theory of operation in increasing level of detail. The 5725A Amplifier is first broadly defined in an overall functional description and block diagram. The overall functional description continues in more detail with functional descriptions by function (ac V, dc I, ac I, and standby). The overall picture is completed with a detailed discussion of how the 5700A and 5725A communicate. The largest part of this section is devoted to detailed component-level circuit descriptions, grouped by assembly.

Warning

Lethal voltage (±500V) appears on the internal heat sink assemblies, and at many other points inside the 5725A chassis. Do not open the 5725A cover without referring to the access procedures and warnings in section 6. Theory text in this section is here strictly for the purpose of describing how circuits work, and contains no access procedures.

Overall Functional Description

4-2.

The 5725A provides three primary functions for the 5700A Calibrator:

Extended frequency range for high ac voltage

High-range dc current

High-range ac current

The 5725A also has a secondary function of sourcing all 5700A current outputs (without the 5700A Current guard) through its own binding posts, if so selected at the 5700A front panel controls. Refer to Figure 4-1, the overall block diagram of the 5725A, for this discussion. Each 5725A function is described briefly next.

1100V AC Function:

The 1100V ac function can output 220 to 1100V, 40 Hz to 30 kHz; and 220 to 750V, 30 kHz to 100 kHz. The 1100V ac function is implemented with a gain of -100 amplifier. Input for the ac voltage function comes from the 5700A Oscillator, spanning the range of 2.2 to 11V. The 5725A returns an oscillator sense voltage of precisely -1/100 of the output voltage to the 5700A. Voltage outputs go through the 5725A/5700A interconnect cable to either the 5700A front or rear panel OUTPUT binding posts.

4-3

Page 61
Image 61
Fluke 5725A instruction manual Introduction, Overall Functional Description

5725A specifications

The Fluke 5725A is a high-performance, multifunctional temperature calibration source designed to meet the demanding requirements of laboratory and industrial environments. Renowned for its accuracy, reliability, and versatility, the 5725A serves as a powerful tool for engineers and technicians engaged in temperature calibration processes.

At the core of the 5725A is its advanced measurement technology, which allows for precision temperature calibrations across a wide range. With an operating temperature range from -200°C to 660°C, it caters to various applications, making it suitable for calibrating thermocouples, resistance temperature detectors (RTDs), and other temperature measurement devices.

One of the standout features of the Fluke 5725A is its outstanding accuracy, boasting a specified uncertainty of just ±0.15°C. This level of precision ensures that users can maintain compliance with regulatory standards and regulatory requirements in fields such as aerospace, pharmaceuticals, and manufacturing.

The Fluke 5725A is equipped with dual-channel capabilities, allowing users to calibrate two devices simultaneously. This enhances productivity by minimizing downtime and optimizing workflow efficiency. The intuitive touchscreen interface simplifies operations, enabling users to view measurements, set up test parameters, and access historical data with ease.

Versatile connectivity options such as USB and Ethernet enable seamless integration into existing systems and allow for data transfer, remote control, and configuration. This feature empowers technicians to conduct calibrations efficiently, whether on-site or remotely.

The robust design of the Fluke 5725A ensures its durability in demanding environments. Built with high-quality materials, it is resistant to shocks and vibrations, making it suitable for use in manufacturing plants and laboratories where equipment may be subjected to harsh conditions.

Another notable characteristic of the 5725A is its ability to generate stable temperature outputs with minimal drift, contributing to consistency in calibration results. Its built-in self-test functionality helps ensure that the unit remains in peak operating condition, giving users confidence in their calibration processes.

In summary, the Fluke 5725A is a top-tier temperature calibration source that excels in accuracy, reliability, and user-friendliness. Whether in laboratory settings or industrial applications, its advanced technologies and features make it an essential tool for professionals tasked with maintaining precision in temperature measurements.