At Zimmer and Peacock we support Zahner instruments, we recently had an enquiry regarding an IM6 instrument at a University, we have paraphrased the technical support below in order to help others.
QUESTION ONE...the impedance in the range 100Hz-1MHz of some polymer membranes which have been sandwiched between two PCB pieces having copper electrodes in touch with the polymer membrane.
-As discussed over the phone the connections must be set as follows:
REFERENCE ELECTRODE-COUNTER ELECTRODE-ELECTRODE 1 ON THE MEMBRANE
TEST ELECTRODE-TEST ELECTRODE SENSE-ELECTRODE 2 ON THE MEMBRANE
This means that the cable outgoing from the reference channel should go into the counter electrode or vice-versa (counter electrode outgoing cable going into the reference)? Does this order make a difference?
Same question for the other connection TEST ELECTRODE-TEST ELECTRODE SENSE.
ANSWER ONE - We would recommend leading the wires of the reference electrode and counter electrode separately from the IM6 to the sample and connect them directly at the sample. The same is true for test electrode and test electrode sense. Separating the current leading and voltage sensing wires is the standard four terminals connection.
QUESTION TWO - I have seen that there is an option of calibration which i have not seen explained in the manual. When should the calibration be done? After having set the connections for two electrodes configuration? Also how to perform the calibration, just by clicking on the option in the software?
ANSWER TWO - All devices come with a factory calibration which will be automatically used when the calibration data CD is installed. The calibration button does a quick offset and gain calibration – the same which is done during startup of the IM6. This helps if the IM6 was started up cold and got warm during use to compensate thermal drift. There is no need to connect some calibration element as this is present within the IM6.
QUESTION THREE - the voltage developed across the piezoelectric polymer membranes (or the current passing through) when they are hit by an acoustic wave of known amplitude and frequency.
-In this case i wouldn't need to apply any voltage, but just measuring it (or the current) across the membrane thickness. What measurement mode must be chosen for this particular measurement.
ANSWER THREE - This is referred to OCP measurement (open circuit potential). Depending on software version the procedure differs a bit.
Older versions use the Pol-Methods, Phase 2 OCP-scan. They are accessible via the I/E, CV icon by selecting Pol. The XT versions can directly use the “Open Circuit Potential” method.
Calibration for this is the same as above.
QUESTION FOUR - Additionally, i have another query. Unfortunately, we are struggling to find the CD to install the software, is it possible to get a new CD or to download the software from online?
ANSWER FOUR - Please give the serial number (should read 12XXX) of the IM6 so we can send the download link for the correct software version for this instrument. Probably you will also require the calibration data, so this will require the serial number, too.