Switch-on delay
Block name
BD12_SWITCHONDELAY
ST call
PROGRAM BD12_TEST VAR IN1,OUT1: BOOL; FB: LIB.CORE.V1_1.BD12_SWITCHONDELAY; END_VAR FB(IN:=IN1); OUT1:=FB.OUT; END_PROGRAM
Library
LIB\CORE
Version
V1.1
Description
The delay block transforms the input signal IN so that each rising edge is delayed by TON. The falling edge of IN is not delayed, it appears on the output immediately. The TRES parameter gives time remaining to the end of delay. The TRES value can be reset by a rising edge on the RESET input.
Inputs
| Input | Type | Description | Default value |
| IN | BOOL | Input value | False |
| RESET | BOOL | Resets the TRES | False |
| IGNORESTARTEDGE | BOOL | If TRUE the block is not initialised after start | False |
| TON | TIME | Rising edge delay (30 s by default). | 30s |
Outputs
| Output | Type | Description |
| OUT | BOOL | Output signal |
| TRES | TIME | Time remaining to the end of delay |
Application example
The usage of this block is very versatile, in fact, this is one of the most used blocks at all. It is used for time insensivity of binary alarms, for sequential switching of cascade members, or for time delays at AHU starting sequence.
Older versions
Version V1.0 is flagged as BROKEN. It contained an error of IGNORESTARTEDGE input. Valu on this input during firt cycle of program was not reflecter even if the function block was set correctly.