Equalising measurement unit esp. electricity meter - increasing value of equalising resistance in steps to produce pre-defined stipulated value

摘要

The measuring unit (17) includes a sensor module (1) duly provided with an input (2) and output (4). A signal (W) at the latter (4) is linearly dependent on an electrical current (IH) at the input. A calculation value is formed from this signal (W) and a reference signal provided by a reference measurement unit. A stipulated value can be attained for this calculation value by increasing the value of a equalising resistance (9,10) in steps. This equalising resistance is provided by a series of resistors (9.1 to 9m or 10.1 to 10n) which are short circuited by respective bridges (11.1 to 11m or 12.1 to 12n). The appropriate bridges are cut to increase the resistance value. ADVANTAGE - Precise, automatic equalising.