Topic: DMD0178

TMRA - Accumulating Up Timer

The Accumulating Timer (TMRA) instruction is a two input leg timer that starts timing up toward the Preset value when the enable leg (EN) is ON and stops timing when the enable leg (EN) is OFF, without resetting the count. The reset (RST) input will reset the timer.

 

Parameters:

Note: Use the F9 key (Element Browser) or Down-Arrow key (Auto-Complete) at any time to see a complete list of the memory locations that are valid in the current field of the instruction.

 

Timer Struct - specifies a unique Timer structure that will be used by this instruction.

 

Preset - is the amount of time after which you want some action to take place. The Accumulating Timer has a resolution of 1 millisecond. The maximum value for a Timer Preset is 2,147,483,647 milliseconds. The Preset value can be specified in one of two ways:

 

Constant - specified using the Time format (HH : MM : SS : mmm).

The maximum Time value in this form is 569 hours, 31 minutes, 23 seconds, and 647 milliseconds. If needed, the value entered for the Timer Preset will be normalized to its standard value. For example, if you entered a value of  97 Seconds, that value will be converted and displayed as 1 Minute and 37 Seconds.

When editing the Constant Preset value, the following keystrokes are available to make entering the value easier and faster:

    • h - takes you to the Hours field

    • m - takes you to the Minutes field

    • s - takes you to the Seconds field

    • mm - takes you to the Milliseconds field

 

Variable - designates a location that contains the total number of milliseconds desired for the Preset. This can be any readable numeric location.

 

Status Display:

The yellow triangle in the upper left corner indicates this is a Multi-Scan instruction.

 

The Accumulating Timer (TMRA) has the following two ladder logic input legs:

 

The first input leg (EN) enables and disables the Accumulating Timer. If this input logic is ON, the Accumulating Timer will begin accumulating time. When this input logic is OFF, the Accumulating Timer will stop timing, but the accumulator and the status flags will retain their current values. If this input logic comes back ON, the Accumulating Timer will continue to accumulate time.

 

The second input leg (RST) is the Timer Reset. If this input logic is ON the Accumulating Timer will reset and the accumulator value will return to 0.

 

The Accumulating Timer instruction provides several status values that can be used elsewhere in your ladder program. Their values are updated each time the TMRA instruction is processed. The syntax for using them is <timer struct>.<flag name>, for example, T7.Acc.

 

  • .Acc (Accumulator) - a 32-bit signed value that represents the total accumulated time whenever the timer was enabled
     
  • .Done - is ON any time the Accumulating Timer's input logic is ON and it's accumulator value (.Acc) is greater than or equal to the Timer Preset value
     
  • .Reset - is ON if the reset (RST) leg's logic is ON, or if the Accumulating Timer is being reset by an RSTT instruction
     

  • .Zero - is ON any time the Accumulating Timer's accumulator value (.Acc) is 0
     

  • .Timing - is ON if the Accumulating Timer is enabled
 

See Also:

 

Rung Example: