Hach POLYMETRON 9135 Operator's Manual page 53

Transmitter 9135 – pH/redox measurement
Note :
Any default detected by the transmitter stops the
controller function.
The default "CONTROL TOO LONG" should be
manually released by pressing ENTER.
If the TIMER and CONTROLLER functions are
activated at the same time, the controller is
stopped during the timer cycle.
Any cycle calculated by the transmitter is carried
out to the end.
FREQUENCY CONTROL :
The pulse width is constant and programmable (0.1
to 0.7 s). The pulse period varies according to the
sample pH value.
S3
T T
On
Off
Period ?
T
T
Time
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