Does anyone have any experience sourcing and communicating with a <b>DVC6200</b> from a Flex I/O <b>1749-OE8H</b>? The AB lit says I may need a 660ohm resistor or a loop power supply, and the Fisher lit says I may need a filter.

 

When the PLC is HART enabled, then no need for a HART filter. 1974 OE8H is HART enabled. Also for the DVC to function well, a minimum voltage of 12VDC (compliance voltage) is required from the I/O at the DVC terminals. No external resistance required. DVC6200, both HW1 and HW2 works with Flex I/O module to a OE2, OE4, or an OE8 modules. Only module OE12 utilizes a power saving feature known as "Dynamic Voltage Regulation" in their output circuit. This feature provides the compliance needed by the connected device with 1 to 2 Vdc of headroom. When this feature is applied with a DVC6200HW2 the DVC may fail to start up and the user sees a fault in the AB PLC interface for "Open Circuit Detected" on the channel.

 

> The AB lit says I may need a 660ohm resistor or a loop power
> supply, and the Fisher lit says I may need a filter.

As per my experience when the PLC is HART enabled, then no need for a HART filter. Old OE8H is HART enabled.

Also for the DVC to function well, a minimum voltage of 12VDC (compliance voltage) is required from the I/O at the DVC terminals.

No external resistance required. DVC6200, both HW1 and HW2 works with Flex I/O module to a OE2, OE4, or an OE8 modules.

 

Resistor usually not required for 4-20 mA/HART valve positioners.

HART filter may be required on some older DCS that are not HART compliant.

HART line conditioner required if you are using the DVC as a Partial Stroke Testing (PST) device on a solenoid valve for a shutdown valve.

See troubleshooting guide here:

http://www.eddl.org/SiteCollectionDocuments/TechPapers/ag_Field Communication Troubleshooting.pdf

Cheers,
Jonas