To drain
127(6DPSOHSUHVVXUHHQWHULQJ
WKHDQDO\]HUPXVWEHUHGXFHGWR
36,%DURUOHVV
Grab sample
valve
6DPSOHZDWHU
IORZPHWHU
3UHVVXUH
UHGXFLQJYDOYH
3UHVVXUH
UHGXFLQJYDOYH
Low pressure
sample water
source
<VWDLQHU
6DPSOH
SXPS
Pressurized
sample water
source
Ex
amp
le
s
for ty
pical sample
wa
ter so
urces
FIGURE 1 (Sample Water Piping Examples)
It should also be considered that the sample point should be located such that the residual reading
can be used as a control signal for the chemical injection. Especially, it should be considered that if
there is a long time delay between chemical injection changes and the change being detected by the
measurement cell, then chemical injection control is adversely aff ected. The delay time should be
kept as short as possible. We recommend that the time be less than 5 minutes.
5
