Answers to the Frequently Asked
Questions about the 767 Calibrated Reference (FAQ)
|
Can I only check
Metrohm instruments with the Calibrated Reference?
No, absolutely not. You can check instruments from other
manufacturers without any problem. You may have to obtain
additional cables or adapters, though. In contrast, all
the cables necessary for Metrohm instruments are included
in the standard accessories supplied with the instrument. |
Can the 767 Calibrated Reference be used
for other applications apart from measuring problems?
Yes, the Calibrated Reference is particularly suitable
for carrying out the regular checks of your instruments
within the framework of a quality assurance program. |
What is the simplest way of carrying out such a regular
check?
To make your work easier, instrument-specific forms
are available from the Info
Center.
You only need to download these forms (pdf), print them
out and then fill them out by hand. These protocols describe,
step by step, the procedure for checking the measuring
inputs. They contain tables for entering the results
of the measurements together with the tolerance values
that apply under normal laboratory conditions. |
I do not have to connect the 767 Calibrated Reference
to the power outlet. How is it then possible for this instrument
to provide a precise potential for checking the pH/mV inputs?
A solar cell, which can be covered by simply turning
a hinged lid, supplies the power for the 767 Calibrated
Reference. If the lighting conditions are inadequate
the output voltage is automatically switched off to prevent
misinterpretations.
When the solar cell is active, the Calibrated Reference
supplies two voltages. One of them has a value of approximately
+1200 mV and is available either directly or via a 1
GΩ resistance. The second voltage is about –340
mV, which corresponds to a pH value of 12.76 (25 °C,
slope = 100%, pHas = 7.00). |
Can I also check my
conductometer and the polarizer of my KF coulometer?
No problem! With the solar cell covered, the Calibrated
Reference supplies resistances of approximately 14.3
kΩ and 460 kΩ. These can be used for checking current
and voltage sources in conductometers, KF instruments,
titrators and pH meters. |
Can I also check my temperature measuring
inputs?
For checking temperature measuring amplifiers, built-in
resistances are used that correspond to the theoretical
values of Pt 100 and Pt 1000 temperature sensors at 0 °C.
Together with the two resistances mentioned above, the
767 Calibrated Reference thus provides a total of four
different resistance values for test purposes. |
Who can give me a guarantee that the values of the
767 Calibrated Reference are correct?
Together with the instrument you will receive a certificate
with traceable measured values.
In the 767 Calibrated Reference we have deliberately
not provided a fine adjustment possibility. This means
that each instrument has slightly different but very
accurately measured set values. The exact values for
each of the parameters mentioned are determined for each
Calibrated Reference before delivery and are printed
out on the cover and on the certificate. All these values
can be traced to international standards. The high stability
of the instrument means that we can recommend an interval
of five years before recalibration is necessary. |
What can you offer me if I want to check more than
just these single measuring points?
The big brother of the 767 Calibrated Reference is the
773 pH/mV Simulator. If the 767 Calibrated Reference
is not adequate for the needs of your service or repair
workshops then we will be pleased to offer you the 773
pH/mV Simulator. This instrument can provide considerably
more different potential values, which is particularly
useful for carrying out linearity checks. |
I think that the 767 Calibrated Reference would be
the optimal instrument for my requirements. What exactly
do I have to order?
You only need to order article no. 2.767.0010. You will
then automatically receive the complete set including
all standard cables in a practical case. |
