ABB PLC Timer : TON, TOF and TP

ABB PLC ladder programming have timer instruction which delayed output to on or off. TON is on delay timer, TOF is off delay timer and TP is pulsed timer. timer instruction declared with timer variable. input (PT) of timer is a preset value which are declared with letter T and a number sign '#' example T#10s and an output of timer is elapsed time of timer. input and output of timer is time data type. timer is very important instruction for plc programming. each timer run only for preset value if prset value (PT) is reached or elapsed than timer coil activated. maximum value for a timer is 49d17h2m47s295ms (4194967295 ms). Elapsed time is a current value of timer. elapsed time store in a time data type with a variable name.

what is time data type in abb plc

time data type defined time constant in plc programming. time resolve in millisecond. each data type have specific range to represent it's value for time data type range is T#0d0h0m0s0ms to T#49d17h2m47s295ms and resolution for time data type is Millisecond. The time constant has a size of 32 bits and a resolution in milliseconds. for high-resolution timers(64 bits) the time constant is LTIME is available as a time basis. The LTIME constant has a dimension of 64 bits and a resolution in nanoseconds. each time value is defined by letter T/t/time/TIME and sign #. syntax for time value is < keyword> # <length of time> where

• keyword : is TIME or time or T or t
• length of time : d: number of days
  • D/d : number of days for example T#1d,Time#2d.
  • H/h : number of hours for example T#1h,Time#2h.
  • M/m : number of minutes for example T#1m,Time#2M.
  • S/s : number of seconds for example T#1S,Time#2s.
  • ms/MS: number of milliseconds for example T#100MS,Time#2ms.

below is the example time variable declaration ton1 declared TON instruction block, variable preset_value_1 is time data type.

how to declared time constant

TIME constants can be declared. These are generally used to operate the timer in the standard library. A TIME constant is always made up of an initial "t" or "T" (or "time" or "TIME" spelled out) and a number sign "#".this followed by the actual time declaration which can include days (identified by "d"), hours (identified by "h"), minutes (identified by "m"), seconds (identified by "s") and milliseconds (identified by "ms"). Please note that the time entries must be given in this order according to length (d before h before m before s before m before ms) but you are not required to include all time increments.

The following would be correct:
• TIME1 := T#14ms;
• TIME1 := T#100S12ms;
• TIME1 := t#12h34m15s;
The following would be incorrect:
• TIME1 := t#5m68s; (*limit exceeded in a lower component*)
• TIME1 := 15ms; (*T# is missing*)
• TIME1 := t#4ms13d; (*Incorrect order of entries*)

abb plc timer input and output parameter

following is input and output variable of timer

input of timer
• IN :bool type timer input
• PT : time type preset value of timer you can use time constant like T#10s, T#1m etc.
output of timer
• Q : bool type output of timer
• ET : elapsed time output of timer use time data type

ABB plc on delay timer TON

TON is on delay timer instruction in abb plc. on delay timer delayed output to turn on when input variable of timer is changed from OFF to ON or false to true. Each timer function block is defined by name when TON function block is declared define timer name.

above is the example of on delay timer in abb automation builder. in this example on_delay_timer is a timer function variable. input of timer is associated with normally open coil input_timer and T#10s is preset value of timer and elapsed_time is output of timer. when timer input is changed from false to true or turn on than timer start and when timer elapsed time reached to preset value than timer output Q is turned on. each change of input timer turned on operation of timer.

ABB plc Off delay timer TOF

TOF is off delay timer in abb automation builder. input and output of off delay timer is same as on delay timer. off delay timer operation start when input of TOF changed from true to false or ON to OFF. OFF delay timer off output of timer when elapsed timer is equal to preset value.

above is the example of off delay timer in abb automation builder. when input of off delay timer is turned on than output if timer also turned on and elapsed time not change. when input of off delay timer changed from on to off than timer start and elapsed time start increment when elapsed timer reached to preset value timer output is set to OFF and timer operation stop.

ABB plc pulsed timer TP

TP is a pulsed timer instruction in abb plc. TP generate pulsed only for specific time period. time period for pulse is declared by preset time(PT) as input. output of TP instruction is ET and Q. when input(IN) is changed from OFF to on than TP instruction start generating pulse and output Q is activated only for preset time. when elapsed time equal to preset time than output Q is turned off. if elapsed time less than preset time than output Q is on.

above is the example of TP pulse timer instruction for abb plc. in this example output timer_out is turned only specific interval. preset is specific interval. in example preset time is 10 second when input of timer is changed from off to on than pulse timer start increment elapsed time value and output is turned on. when elapsed time is equal to or greater than preset time than output of pulse timer is turned off.