AMETEK 7100 Leak Detect Stik - Manual (Page 11)

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NOTE 1: ts-s = time from 1st start pulse in one frame to next start pulse in the next frame.
NOTE 2: Start pulse can start anywhere in the 4.5 ms frame. The stop pulse will follow at the correct time.
The ts-s is not consistent. The user does not have the 4.5 ms frame as a reference. The user must
use the watchdog timeout during the pause frame to “sync up”. The watchdog timer should be reset
on both the start and stop pulse.
NOTE: Although the timebase is generated with a crystal oscillator, the times shown are NOT exact times.
Also, the initial pulse within a window of the frame does not start at the beginning of the window. See
Section 3.1: Synchronizing with a Watchdog Timer and footnote 3 for more information.
Figure 5: Pause Period Timing
Reset Reset Watchdog Watchdog
4.5mS
ts-s
4.5mS
4.5mS 9mS 4.5mS
Product
High Re
f
Pause
Temp #1
W
ater
#15 #16 #1 #2 #3
Figure 4: Start Pulse