Metrohm 773 pH/mV Simulator - Manual (Page 8)

2.3. Checking the insulation of the separate reference point
773 pH/mV Simulator
6
2.3 Checking the insulation of the separate reference
point
773 pH/mV Simulator
x100
x10
x1
-
-
14,3k PT1000 PT100 RE WE WE ON/OFF
pH U/mV
- +
20
6
4
2 18
16
14
12 10 8
0
+ +
0
20
25 40 60 80
100 C
1000 ~0,002
pH=7
U=0mV
i R /M
1. Set up the instruments as for checking the U value.
2. In addition connect the earthing socket of the 773 pH/mV Simu-
lator with the earthing socket of the instrument being checked.
For instruments with earthed measuring inputs (e.g. Titrinos) this check is irrele-
vant.
3. On the 773 pH/mV Simulator press the key beside the earthing
socket and keep it pressed until the measured value drift is sta-
ble.
The measured value with the key depressed should not differ by
more than 2 mV from the value obtained without pressing down
the key.
2.4 Checking the temperature compensation for pH
measurements
773 pH/mV Simulator
x100
x10
x1
-
-
14,3k PT1000 PT100 RE WE WE ON/OFF
pH U/mV
-
+
20
6
4
2 18
16
14
12 10 8
0
+ +
0
20
25 40 60 80
100 C
1000 ~0,002
pH=7
U=0mV
i R /M
1. Set up the instruments as for checking the pH.
2. Set pH 13 on the 773 pH/mV Simulator.
3. Set the measuring temperature of the instrument being checked
to 0 °C. Set the temperature on the 773 pH/mV Simulator to 0 °C
as well.
The measured value must only vary within the given tolerances.
These tolerances can be found in the ‘Instructions for Use’ of the
instrument being checked.
4. Carry out the same check at 100 °C.
6.2150.040 Cable
6.2150.000 Cables keep key pressed
6.2150.040 Cable