Fluke 789 Process Meter

Fluke 789 Process Meter

The Fluke 789 Process Meter is a sophisticated device that features the measurement functions of a digital multimeter alongside the system-testing functions of a loop calibrator. It offers precision measurement of AC/DC voltage (1000V), AC/DC current (440mA, 1A for 30s max), resistance (40MΩ), and frequency (20kHz) in addition to continuity and diode testing. Parameters are accurately measured to high resolutions including to µA for current. When using the device as a multimeter, the user can use min/max/avg recording and data hold which maintains stable readings on screen. Relative mode produces a relative zero reading which permits, for example, compensation for test lead resistance during resistance measurement. True RMS measurement improves the accuracy of readings for AC values and further flexibility is given by a choice between automatic and manual ranging. It is therefore a very handy multimeter.

The loop calibration capabilities of the Fluke 789 are arguably even more impressive than the multimeter functions. Firstly the 24V loop power supply means there is no need for a separate power source and a DC test current of between 0 and 20mA can be forced through resistance of up to 1200Ω. The 0% and 100% buttons allow the user to toggle between 4 and 20mA for both sourced and simulated current for speedy span checking and there are several different options for ramping and stepping including auto-ramp and auto-step as well as four different manual step options. Furthermore, the HART mode and integrated 250Ω resistor negate the requirement to carry a separate resistor.

Two brightness settings for the Fluke 789’s large, dual display allow adjustment for light levels and all readings are clearly shown. The user interface has clearly labelled push buttons and a simple dial so the measurement parameter or loop calibration mode are displayed both on screen and by the dial. In terms of safety, an indication of dangerous voltage is shown on screen and the inputs are rated Cat III to 1000V and Cat IV to 600V so the user can have confidence when using the device. It comes supplied with red/black test leads, test probes and crocodile clips alongside product documentation.

Fluke part number: 789

Key Features

• Measures voltage, current, resistance and frequency
• Continuity and diode testing
• Min/max/avg recording
• Data hold
• Relative zeroing
• True RMS measurement
• 24V loop power supply
• Simulates and sources test current between 0 and 20mA
• Drives current through resistance up to 1200Ω
• 0% and 100% for span check between 4mA and 20mA
• HART mode and built-in 250Ω resistor
• Auto-step, auto ramp, manual step and manual ramp
• Large backlit dual display
• Simple dial and push button operation
• Cat III to 1000V and Cat IV to 600V
• Supplied with red/black test leads, probes and crocodile clips

For more information on Fluke 789 Process Meter talk to www.test-meter.co.uk