Hewlett-Packard's 3455A Digital Voltmeter is a 6 1/2-digit integrating voltmeter for bench or systems applications. The standard instrument measures dc volts, ac volts, and resistance. HP-IB and auto or manual ranging are also standard.
The HP 3455A is fully guarded and has greater than 60 dB normal mode noise rejection at reading rates of up to 24 readings per second on all dc ranges. Ohms reading rates are up to 12 readings/second and an ac fast mode gives reading rates of up to 13 readings/second at frequencies above 300 Hz. (Readings/second given for 60 Hz operation and high resolution off.)
DC measurements can be made with up to 1µV sensitivity. Ohms measurements are made with either a 2-wire or 4-wire mode. The high resolution (6 1/2-digit) mode gives dc and ohms measurements with greater than 1 part per million resolution. The standard true rms ac to dc converter measures sinusoid and complex signals with crest factors up to 7:1 at full scale from 30 Hz to 1 MHz.