Matrox 4Sight EV6, Installation And Hardware Reference

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Migrating an auxiliary input wired to a sinking field device that relies on a pull-up resistor 101
Migrating an auxiliary input wired to a
sinking field device that relies on a pull-up
resistor
To guarantee that a Matrox 4Sight EV6 auxiliary input can reliably replace a
Matrox 4Sight GPm auxiliary input, wired to a sinking field device, the pull-up
resistor value must allow sourcing a current of up to 2.25 mA thought the input.
In addition, there must be a voltage drop of at least 11 V across the
Matrox 4Sight EV6 and AUX_INn- pins. This verification is
required to ensure reliable operation in an industrial environment. If using 24 V,
then the pull-up resistor value must be less than 5.77 Kohms. If using a reference
voltage below 24 Vdc, the pull-up resistor value must be equal to or less than the
value given by the following formula:
Pull-up resistor value
ReferenceVoltage 11 V
–
2.25 mA
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