Nuclear Associates 76-908 & 76-907

Operators Manual

DC-Offset Errors

DC-offset errors typically appear as a single bright pixel (sometimes as a dark pixel if overflow or processing has occurred) at the center of the image matrix. The existence of this error is assessed visually.

Receive Quadrature Errors

Receive quadrature ghosts will be evaluated using the central slice of the multi-slice sequence acquired with the phantom at the isocenter. Receive ghosts will appear upside down and reversed from the true signal producing objects (object in the upper left-hand corner will appear as a ghost in the lower right- hand corner). Regions-of-interest values are taken from both the true image and the ghost image. The receive Quadrature Error (E) is quantified by expressing the ghost ROI value (G) as a percent of the true ROI (T).

E = ((T-G/T) x 100%

Transmit Quadrature Errors

Transmit quadrature ghosts are evaluated using images acquired in the multi-slice mode in which the phantom is placed at a location offset from the isocenter. A transmit ghost appears in the slice located in the opposite offset direction at a distance equal to the distance at which the true object is located from the isocenter (mirror image from the isocenter). The ghost and true object image will be located at the same relative positions in their respective images. For example, a true object located in the upper left comer at a distance of +5 cm from the isocenter will produce a transmit quadrature ghost in the upper left comer of the image at -5 cm ROl's taken over the true object and the ghost are used to determine the percent error

(E).

E = ((T-G)/T) x 100%

2.4.4 Action Criteria

Phase related errors should typically be less than 5% of the true signal value. DC-offset errors should not be present in images from a properly functioning system.

2.4.5 Example Images

Figure 2-9 is an image of the linearity section of the phantom demonstrating the non-linearity that exists in the magnetic field especially on the outer edge of the field of view. Three black squares are markers for phantom orientations.

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Fluke 76-908, 76-907 user manual Action Criteria, DC-Offset Errors
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76-908, 76-907 specifications

The Fluke 76-907 and 76-908 are advanced digital multimeters designed to cater to the needs of professionals and technicians in diverse fields. Known for their accuracy, durability, and versatility, these instruments have become essential tools for electrical measurement and troubleshooting.

One of the standout features of both the Fluke 76-907 and 76-908 is their superior measurement capabilities. These multimeters can measure AC and DC voltage, current, resistance, frequency, and temperature with impressive precision. The devices are equipped with a large LCD display that provides clear readings, even in low-light conditions, making it easy for users to take measurements in various environments.

The Fluke 76-907 is particularly recognized for its ergonomic design, ensuring comfort during prolonged use. It includes a built-in flashlight to illuminate dark work areas and an adjustable backlight for improved visibility of the display. Additionally, the device features a rugged casing that protects it from drops and impacts, enhancing its longevity and reliability in demanding job sites.

On the other hand, the Fluke 76-908 offers advanced features such as Bluetooth connectivity, enabling users to connect the meter to compatible smartphones and tablets. This feature allows for seamless data transfer and real-time monitoring of measurements via an intuitive app. The integration of wireless technology facilitates remote measurements, which is crucial in hazardous environments where direct access may be restricted.

Both models utilize advanced technology, including True RMS measurements, which ensure accurate readings of complex signals. This is particularly beneficial for professionals working with variable frequency drives, non-linear loads, and harmonics. The Fluke 76-907 and 76-908 also come equipped with a range of safety features, including CAT III and CAT IV ratings, ensuring they can safely handle high-voltage applications.

Battery life is another essential characteristic of these multimeters. Both models are designed for extended usage with efficient power management systems, minimizing downtime caused by battery replacements.

Furthermore, the Fluke 76-907 and 76-908 are straightforward to operate, featuring a user-friendly interface that allows technicians to navigate functions easily. They are ideal for various applications, from routine maintenance and troubleshooting in electrical systems to complex diagnostics in industrial settings.

In conclusion, the Fluke 76-907 and 76-908 digital multimeters stand out for their precise measurements, robust design, and innovative technology. Whether for fieldwork or onsite diagnostics, these multimeters provide reliability and efficiency, making them indispensable tools for professionals in the electrical industry.
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