GE 90-30/20/Micro manual Tmr

4

TMR

The simple on-delay timer (TMR) function increments while it receives power flow and resets to zero when power flow stops. Time may be counted in tenths of a second (the default selection), hundredths of a second, or thousandths of a second. The range is 0 to +32,767 time units. The state of this timer is retentive on power failure; no automatic initialization occurs at power-up.

When the TMR receives power flow, the timer starts accumulating time (current value). The current value is updated when it is encountered in the logic to reflect the total elapsed time the timer has been enabled since it was last reset.

Note

If multiple occurrences of the same timer with the same reference address are enabled during a CPU sweep, the current values of the timers will be the same.

This update occurs as long as the enabling logic remains ON. When the current value equals or exceeds the preset value PV, the function begins passing power flow to the right. The timer continues accumulating time until the maximum value is reached. When the enabling parameter transitions from ON to OFF, the timer stops accumulating time and the current value is reset to zero.

a42933

ENABLE

Q

AB C D E

A= ENABLE goes high; timer begins accumulating time.

B= Current value reaches preset value PV; Q goes high, and timer continues accumulating time.

C= ENABLE goes low; Q goes low; timer stops accumulating time and current time is cleared.

D= ENABLE goes high; timer starts accumulating time.

E= ENABLE goes low before current value reaches preset value PV; Q remains low; timer stops accumulating time and is cleared to zero.

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(enable)Q

time

(preset value) —PV

_____

(address—3 words)

4-14 Series 90-30/20/Micro Programmable Controllers Reference Manual–September 1998 GFK-0467K