Unique to Fluke, the 771, 772 and 773 Milliamp Clamp Meters are engineered to accurately measure the minute amounts of current (4mA to 20mA signals) that flow through control system circuits, without having to shut down the system, break the circuit and insert a test instrument. Instead, sensitive current clamps placed around the wire detect and measure the current flowing through. In addition, the Fluke 772 and 773 can be used to simultaneously source, simulate and measure milliamp signals in a broken circuit, negating the need for additional tools. The Fluke 773 will also source and measure DC voltages for troubleshooting voltage input and output devices; will power a transmitter for independent checking of its mA output signal; and will provide a scaled output signal to provide datalogging by a Fluke 280 Series Digital Multimeter, for example.
Without breaking the loop, the backlit display will give simultaneous milliamp and percentage span readings, with milliamp resolution to 0.01mA. The Fluke 771/772/773 feature a unique detachable clamp that can be used docked, or detached via its extension cable to facilitate measurement in tight spaces, and a Hold function to capture and display changing measurements for convenient viewing. A built-in flashlight illuminates wires in dark enclosures, and a battery saving feature cuts in automatically after prolonged inactivity. Users can also measure 10-50mA signals in older control systems using a 99.9mA range.