The 2440C Source Meter combines a precise, low-noise, highly stable DC power supply with a low-noise, highly repeatable, high-impedance multimeter. It has 0.012% basic accuracy with 5Tone-digit resolution. At 5Tone digits, the SourceMeter delivers 520 readings/second over the IEEE-488 bus. At 4Tone digits, it can read up to 2000 readings/second into its internal buffer. The contact check function detects measurements that may be in error due to excessive resistance in the force or sense leads when making remotely sensed (Kelvin) measurements. The unit has broad source and measurement ranges: Source voltage from 5V to 42V; measure voltage from 1V to 42V. Source current from 500pA to 5.25A; measure current from 100pA to 5.25A. Measure resistance from 10 (<10 in manual ohms) to 21.1M.Tone Maximum source power is 66W.