As of March 24, 2017, some of the 590+ encoder option cards were discontinued.
Specifically, AH387775U005, AH387775U012, AH387775U015, and AH387775U024 were discontinued and no longer offered.
All of these versions can be replaced by model AH387775U001.
NOTE - do not connect your encoder to the card until the voltage calibration procedure has been completed.
The -005, -012, -015, and -024 versions were simply pre-configured for a specific voltage requirement. The -001 version is not pre-configured at the factory but supports all of the voltages the pre-configured versions supported. Customers will need to follow a simple calibration procedure to match the required voltage.
The calibration and installation information can be obtained from this link: