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Tof (timer off-delay), Tof (timer off-delay) -6 – Sensaphone SCADA 3000 Users manual User Manual

Page 162

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15-6

SCADA 3000 User’s Manual

Element Function
Number Description

Range of Values

0

Timer Enabled

0 or 1 (0=disabled, 1=enabled)

1

Timer Running

0 or 1 (0=disabled, 1=enabled)

2

Timer Done

0 or 1 (0=disabled, 1=enabled)

3

Preset Value

0 to 32,767

4

Timer Value

0 to 32,767

Examples:

T,0,0 indicates if Timer 0 is enabled or disabled.

T, 12,4 references the current timer value of timer number 12.

The timer value and status bits can be viewed or changed from the Timer Status form. To view

the timer values, click on the Ladder and C Variables button from the Toolbar on the Main

Programming form. Select the Timers tab. In addition to viewing the state of the timer values,

you can also force changes by double-clicking on the timer value you want to change. A Change

form will appear to let you enter a new value for the timer. Use the Up/Down arrows to flip

through the pages to access the timers you wish to view.

TOF (Timer Off-Delay)

This instruction is used to turn an output ON or OFF after the rung has been false for a pre-

set time interval. The specified timer starts running when the rung status changes from true

to false. The timer starts at 0 and counts up to the PRESET value. The TIMER VALUE will

continue to increment as long as the rung remains false, until it reaches the PRESET value. If

the rung becomes true, then the timer stops and resets to 0, regardless of whether the timer has

timed-out. The timebase for the TOF instruction is .01 seconds (for example PRESET = 500

is 5 seconds). The timer bits are updated as follows:

ENABLED: Set when rung is true, and reset when rung becomes false.
RUNNING: Set when rung is false and the TIMER VALUE is less than PRESET

value, and reset when rung is true or when DONE bit is reset.

DONE: Set when rung is true, and reset when rung becomes false and the TIMER

VALUE is greater than or equal to the PRESET value.

The timer address can only reference one of the 64 internal timers T,0 through T,63. Right-

click on the instruction and choose Select Timer. A list of the 64 timers will be displayed. Select

one and click OK. Set the Preset by right-clicking on the instruction and choosing Set Preset.

Enter the preset value and click OK.
The instruction executes in 4.5µs and requires 84 bytes.

Note: The RESET (RES) instruction cannot be used with the TOF instruction.

The GROUP for this type is the timer number from 0–63. The ELEMENT specifies an indi-

vidual function for the selected timer. There are 5 functions associated with each timer: