Migrating An Auxiliary Output Wired To A Sinking Field Device; That Relies On A Pull-Up Resistor - Matrox 4Sight EV6 Installation And Hardware Reference

Migrating an auxiliary output wired to a sinking field device that relies on a pull-up resistor
These changes improve the immunity of the unit, and optionally allow
maintaining an electrical isolation between all interfaced field devices. This
implementation requires that each auxiliary input/output is referenced
independently, unlike the Matrox 4Sight GPm auxiliary inputs/outputs that only
needed a single negative pin to be used as a reference for all of the auxiliary
inputs/outputs.
The following connections should still operate seamlessly:
• Interfacing Matrox 4Sight EV6 auxiliary inputs to sourcing devices that were
previously interfaced to Matrox 4Sight GPm auxiliary inputs using a 24 V
reference voltage, without connecting external resistors.
• Interfacing Matrox 4Sight EV6 auxiliary outputs with sourcing devices that were
previously interfaced to Matrox 4Sight GPm auxiliary outputs using a 24 V
reference voltage. Sourcing devices must meet specifications for 24 Vdc digital
inputs of either type 1, 2, or 3 as per the EN 61131-2:2007 standard.
 Note that interfacing Matrox 4Sight EV6 auxiliary inputs/outputs with any
wiring involving the presence of external resistors requires proper verifications.
Migrating an auxiliary output wired to a
sinking field device that relies on a pull-up
resistor
To guarantee that a Matrox 4Sight EV6 auxiliary output can reliably replace a
Matrox 4Sight GPm auxiliary output, wired to a sinking field device, the device
must meet the specification of industrial 24 V
or 3, as per the EN 61131-2:2007 standard. If this is not the case (that is, the
sinking field device V
Matrox 4Sight EV6 auxiliary output might prevent the sinking field device from
recognizing a low logical state when the output is closed.
To migrate a sinking field device whose V
either re-wire the device in a typical complimentary sourcing-to-sinking
connection, or you can add a serial resistor between the AUX_OUTn- and INPUT
pins. Adding a serial resistor will limit the current circulating through the sinking
field device, which means you will need to consider the total voltage drop across
threshold is below 3.0 V), the voltage drop across the
LMAX
LMAX
digital inputs of either type 1, 2,
dc
threshold is below 3.0 V, you can
99