The documentation that comes with the FP-QUAD-510 does not clearly mention that you absolutely MUST supply external DC power in order for the input channels to function. Figures 3 and 4 of the Operating Instructions are missing a wire showing connection of the external power supply to the Input Circuitry block. Other parts of the document mention that operating power is supplied by the network module through the terminal base. This is misleading, as you must also connect external power, not only if you are powering the encoder through the +5V output.
