1-2. The Model 721A Lead Compensator is a device designed to compensate for the effects of lead and contact resistance in voltage-divider measurement circuits. It is particularly useful in those situations demanding the utmost in accuracy. It is a useful operational accessory for such high-accuracy voltage dividers as the John Fluke Model 720A and Model 725A. 1-3. SPECIFICATIONS 1-4. ELECTRICAL RESOLUTION OF RESISTANCE COMPENSATION 0.1 milliohm. MAXIMUM RATIO BETWEEN DIVIDER RESISTANCES 4000 to 1. MAXIMUM ALLOWABLE LEAD RESISTANCE 150 milliohm s. MAXIMUM DIVIDER VOLTAGE 1500 volts, dc or peak ac. 1-5. MECHANICAL FINE CONTROL 10-turn, 150-milliohm, slide-wire potentiometer. COARSE CONTROL 18-position rotary switch. BINDING POSTS Gold plated copper. VOLTAGE SWITCH Grounds input voltage terminals to permit compensation for thermal voltages. DIMENSIONS 3-1/2 high x 19" wide x 6" deep.