Fluke 771 Milliamp Process Clamp MeterFluke 771 Milliamp Process Clamp Meter Save time by measuring 4 20 mA signals without breaking the loop The Fluke 771 delivers all the basic functionality you would expect in a milliamp clamp meter. It measures 4 20 mA signals without "breaking the loop," allowing you to measure low level DC current without having to take systems offline for troubleshooting, saving downtime and money. You can also use it to measure output signals from transmitters