Current to voltage 4-20mA

Modern 4-20mA systems nominally use 24Vdc to power supplies to power a device that provides data in a format represented as a mA signal, this signal is then converted to a voltage for instrumentation or computer manipulation, this voltage can be presented in various formats, nowadays the two most commonly used formats are 1- 5, and 2 - 10 volts, these are most commonly obtained by passing the 4-20mA through high precision resistors that present a 250 or 500 Ohm load to the mA signal, these resistors may not in themselves be exactly that resistance, as they may have to compensate for other circuit components in the system. http://everycircuit.com/circuit/6619279043330048

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