SEL_PID2: Selector 2 for PID; input , n.FB
Block SEL_PID2 (FB452) forms a selector function (n-to-1 assignment) together with SEL_PID1 and SEL_PID3.
Block SEL_PID2 bundles 4 inputs (2xToHi and 2xToLo) and permits their enable using just one signal [EnInVal].
Principle of operation
Blocks SEL_PID1 and SEL_PID2 bundle 4 inputs each. The enabled input values [EnInVal] = True, are read in sequence by block SEL_PID3 and outputted.
Inputs
Pin | E | Description |
BlkRefIn | pa | Block reference input Interconnection with SEL_PID1 or SEL_PID2. This implements selector function (n-to-1). |
EnInVal | pa | Enable input values Block SEL_PID3 outputs all input values of this block. |
To higher neighbor element 1. | pa | To higher neighbor element 1. Record input value |
ToLo1 | pa | To lower neighbor element 1. Record input value |
ToHi2 | pa | To higher neighboring element 2 Record input value |
ToLo2 | pa | To lower neighboring element 2 Record input value |
Outputs
Pin | E | Description | |
BlkRefO | a | Block reference output Interconnect with SEL_PID2 or SEL_PID3. This implements selector function (n-to-1). | |
ErrRef | a | Reference error | |
1 (Yes) | No values are outputted at block SEL_PID3.
| ||
0 (No) | Normal function. | ||
Engineering selector function (n-to-1)
Together, blocks SEL_PID1, SEL_PID2 and SEL_PID3 form a selector function (n-to-1).
The following interconnection is important for the correct function.
- Block SEL_PID1 is the first block in the interconnection sequence. It bundles the first 4 inputs.
- One or more SEL_PID2 each bundle additional inputs. Blocks are interconnected to one another via [BlkRefIn] and [BlkRefO].
- Block SEL_PID3 concludes the selector function. It is interconnected via [BlkRefIn] and [BlkRefO] with SEL_PID1 or SEL_PID2.
- The processing sequence is important to proper functioning and must be optimized prior to compiling the chart using the CFC command Optimize chart.
- Only a single block (SEL_PID1, SEL_PID2) is enabled (the last enabled SEL_PID2 in the processing sequence has precedence).
Note: During the initial programming loop, it checks whether interconnection is correct and whether the version of the three blocks is identical. If not, [ErrRef] = 1 (Yes) and no input values are outputted on block SEL_PID3.
Process response
Standard (see General rules and information).
Troubleshooting
Standard (see General rules and information).