Description
This function block set is used to monitor if there is fan differential pressure before and after a filter switches on. If yes, an alarm is generated to inform maintenance personnel of cleanup.
Function
The function block set starts timing when "Supply Fan Status" is "1" (0-OFF/1-ON) and outputs "Filter Differential Pressure Alarm" as "1" if "Filter Differential Pressure Status" is detected as "0-OPN" after the counted time exceeds "Differential Pressure Time Delay". It doesn’t generate an alarm if the differential pressure status is "1-CLS".
Internal logic
Input
PIN | Data type | Unit | Default value | Value/range |
|---|---|---|---|---|
SF_STA | BOOL | - | 0 | 0-OFF / 1-ON |
FILT_DPS | BOOL | - | 0 | 0-OPEN / 1-CLOSE |
TIME_DELAY | FLOAT | s | 30 | 0...65535 |
Output
PIN | Data type | Unit | Default value | Value/range |
|---|---|---|---|---|
FILT_DP_ALM | BOOL | - | - | 0-OK / 1-FLT |
Example
