I/O Blocks > H1 Carrier Multiple Discrete Input (FFMDI) function block

H1 Carrier Multiple Discrete Input function block execution

I/O Selection

When you configure the H1 Carrier Multiple Discrete Input function block, you assign the block to an FFMDI block in an H1 Carrier device. The carrier device, when fully installed, has a Discrete Input card and a Discrete Output card connected to it. Assigning the block to the carrier connects FIELD_VAL_D to the eight channels on the Discrete Input card. FIELD_VAL_D is the last 8-bit integer value reported by the card and the current status of the carrier.

Simulation

To support testing, you can enable simulation. This allows the measurement value and status to be supplied manually.

When the value is entered manually:

When SIMULATE_D is not enabled, the hardware value becomes the FIELD_VAL_D parameter value in the block. When SIMULATE_D is enabled, the simulated value and status becomes the value and status of FIELD_VAL_D.

Field Value Processing

Invert — You can configure the Invert I/O option (IO_OPTS) to process FIELD_VAL_D.

Selecting the invert option causes all channel values to be inverted. The output of the Invert processor is PV_D. You might select this option when the field contact is normally closed so that an open contact or a broken wire represents the active state of the condition being sensed.

Note

You can set the I/O option in Out of Service mode only.

PV Filter — Filtering in a H1 Carrier Multiple Discrete Input function block is performed with on and off delays. FIELD_VAL_D must be on (or off) for PV_FTIME without changing before the block passes a change to PV_D. PV_FTIME is applicable for all of the channels.

Block Errors

The following conditions are reported in the BLOCK_ERR parameter:
  • Simulate active — SIMULATE_D is enabled; therefore, OUT_INT is not real.

  • Input failure/process variable has Bad status — The source of the block's process variable is bad.

  • Out of Service — The block is not being processed.

  • Other Error — The block is not communicating with the carrier.