Fluke 789 (14577) is a combined true-RMS digital multimeter and 24 V loop calibrator: it measures 0-1000 V AC/DC, 0-1 A AC/DC current, resistance to 40 MΩ and diode drop, and sources 0-20 or 4-20 mA with 1200 Ω / 24 V drive capability. Current output can be stepped or ramped, with simultaneous display of value and percent of span; DC accuracy is 0.2 % + 2 LSD. Suitable for process-instrument service where a technician needs both meter and loop source in a single tool; operating temperature -20 to 55 degrees C.