The inputs provided to this function block are press, autoSetOffset, and clearOffset. The output pins are flow, offset , and vel.This function computes the flow and velocity based on the measured pressure and the K factor.
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and
Vel = flow/area
Where:
Analog Inputs
| Range | ||||
| Input Name | Low | High | Input Value | Description |
| press | > = - infinity | < + infinity | unconnected | output set to invalid |
| invalid | output set to invalid | |||
| > - 0.002425 and < 0.002425 inw | Flow and vel = 0 | |||
| autoSetOffset | > = - infinity | < + infinity | unconnected | No effect on output |
| invalid | No effect on output | |||
| !=0 | set offset = incoming press | |||
| clearOffset | > = - infinity | < + infinity | unconnected or invalid | No effect on output |
| !=0 | set offset = 0 | |||
| area | > = - infinity | < + infinity | Invalid or < = 0 value in ft ** 2 |
Velocity set to invalid |
| kFactor | > = - infinity | < + infinity | unconnected | output set to invalid |
| invalid | output set to invalid | |||
| <= 0 | kFactor = 1015 | |||
Output
| Range | |||
| Output Name | Low | High | Description |
| FLOW | > = - infinity | < + infinity | Flow value (ft **3/min) |
| OFFSET | > = - infinity | < + infinity | Input press offset correction (inches water column). Not for connection. Stores Flow offset amount. |
| VEL | > = - infinity | < + infinity | Flow velocity (ft/min) |