The null balance system enables the 1024 to be used for making accurate current measurement in addition to its basic function as a calibrator. Operation is by backing the current source output against the current to be measured, with the difference being displayed on a sensitive centre zone null meter. At the null point, there is no voltage drop across the 1024.
The 1024 employs a precision aged reference diode as a basic reference source. Excellent zero stability is ensured by the use of a high performance FET chopper amplifier system. Precision metal film resistors with temperature coefficients of less than 10ppm per °C are used to maintain the accuracy and stability of the initial calibration.
The 1024 can be powered from mains supply or by the internal rechargeable battery pack.
When the calibrator is plugged into the mains supply the internal batteries will automatically start to recharge.
If unplugged from the mains during operation the internal batteries will continue to power the instrument. Full charge allows 12 hours typical use. The battery condition monitored by a meter on the front panel.