Hall-Sensor Current Monitor
Posted on May 22, 2012 12178
The circuit uses a Hall-effect sensor, which consists of an IC that resides in a small gap in a flux-collector
toroid, to measure dc current from 1 to 40 A. Wrap the current-carrying wire through the toroid; the Hall voltage Vh is then linearly proportional to the current (/). The current drain from Vb is less than 30 mA. To monitor an automobile alternator"s output current, for example, connect the car"s battery between the circuit"s VB terminal and ground, and wrap one turn of wire through the toroid (or, you could wrap 10 turnsâ€”if they"d fitâ€”to measure 1 A full-scale). When 7=0 V, the current sensor"s (CSl"s) VH output equals one-half of its 10-V bias voltage, VH and Vout arc zero when I is zero; you can then adjust the output gain and offset to scale Vout at 1 V per 10 A. 1. C1 and C2 ARE 199D TANTALEX CAPACITORS FROM SPRAGUE. 2. L1 IS A 6860-23 INDUCTOR FROM CADDELL-BURNS. 3. R1A, R1B AND R1C ARE PART OF A THIN-FILM RESISTOR NETWORK SUCH AS THE CADDOCK T914-10K 4. CS1 IS A HALL-EFFECT CURRENT SENSOR (CSLA1CD) FROM MICROSWITCH.