Xylem WTW SenTix ORP-T 900, Operation Manual

Page: 6 / 14

Commissioning, measuring, checking SenTix
®
ORP-T 900(-P)
6
ba75845e03 02/2017
 Avoid the carryover of sample solution from one measurement to the next
as follows:
– Shortly rinse the sample beakers with the solution the beakers are to
be filled with next.
– Between measurements, rinse the electrode with the solution that fol-
lows. Alternatively, you can also rinse the electrode with deionized
water and then carefully dab it dry.

Immerse the electrode in the solution in a vertical or slightly tilted position.
 Make sure the immersion depth is correct. The junction must be com-
pletely submersed in the solution. The junction is in the area of the bottom
end of the shaft (see arrow).
At the same time, the level of the reference electrolyte must be at least 2
cm above the level of the solution.
Conversion to
normal hydrogen
electrode
U
H
= U
Meas
+ U
Ref
U
Ref
is temperature dependent and can be taken from the following table (see
also DIN 38404-6):
SenTix
®
ORP-T 900(-P)
with: U
H
= ORP, referring to the normal hydrogen electrode
U
Meas
= Measured ORP
U
Ref
= Voltage of the reference system compared to the normal
hydrogen electrode
T (°C) T (°F) U
Ref
[mV] T (°C) T (°F) U
Ref
[mV]
SenTix
®
ORP-
T 900
SenTix
®
ORP-T 900
0 32 +224 35 95 +200
5 41 +221 40 104 +196
10 50 +217 45 113 +192
15 59 +214 50 122 +188
20 68 +211 55 131 +184