Electrical standard calibration test unit - uses multi-purpose unit for voltmeter, ammeter, or other types of calibration

摘要

The electrical calibration unit has terminals for connection to the main and a nickel cadmium battery supply. The unit has a current generator which can be supplied from a range of several voltages and which operates over several current ranges. The unit has a multirange voltmeter with automatic switching and display. It also has a relay switching circuit with three multiposition switches for voltages (18), currents (19) ranges and test (20) functions. The units has a control panel (11) housing controls, terminals, socket outlets fuses and an on off switch (15). The current generator is an operational amplifier and is fitted with a rotatable potentiometer (16) for fine current adjustment. The unit has an electronic voltage and current display (22) with indication (23) of measuring units m A, A, m V or v.