Page 385 - Programmable Logic Controllers, Fifth Edition - Mobile version

L1 Inputs Ladder logic program Outputs L2
Stop_PB Start_PB
<Local:1:I.Data.0> <Local:1:I.Data.1> Internal_Relay
Stop_PB Event_1 G
Internal_Relay
Event_2 G

Internal_Relay
Start_PB TON
Timer On Delay EN Complete R
Timer Timed_Event_1
Preset 3000 DN
Accum 0

Timed_Event_1.DN TON
Timer On Delay EN
Timer Timed_Event_2
Preset 10000 DN
Accum 0

Timed_Event_2.DN
TON
Timer On Delay EN
Timer Timed_Event_3
Preset 5000 DN
Accum 0
Event_1_Complete_PL
Timed_Event_1.DN <Local:2:0.Data.0>

Event_2_Complete_PL
Timed_Event_2.DN <Local:2:0.Data.1>

Process_Complete_PL
Timed_Event_3.DN <Local:2:0.Data.2>

Figure 15-64 Cascading TON timers for timed event-driven routines.

Input Ladder logic program Output
Limit_Switch
<Local:1:I.Data.0> Timer_Reciprocating_On.DN
TON
L1 Timer On Delay EN L2
Timer Timer_Reciprocating_O
Preset 2000 DN
Limit_Switch Alarm_PL R
Accum 0
Timer_Reciprocating_O .DN
TON
Timer On Delay EN
Timer Timer_Reciprocating_On
Preset 2000 DN
Accum 0
Alarm_PL
Timer_Reciprocating_O .DN <Local:2:0.Data.0>

Figure 15-65 Flashing pilot light program.

366 Part 3 Programming Timers

pet73842_ch15_333-394.indd 366 03/11/15 7:33 PM