London Electronics IL2-L, Connection Details, Scaling And General Information

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Error codes and fault finding
--Ur--
--Or--
1. Under Range. The meter is being asked to display a value which is more
negative than its limit of -199999
2. Over Range. The meter is being asked to display a value which is higher
than its limit of 999999
If no loadcell is connected to the display, you will see one of these fault
codes.
In addition, these fault codes could be displayed because the signal is too
negative, too positive, or because there is a wiring error, or because the
display’s scaling has been adjusted to give excessive sensitivity, or because
there is a fault in the display.
a. Measure the input signal on terminals 3(-) and 4(+)and confirm that it is
between -40mV DC and +40mV DC. You can temporarily force the dis-
play’s input signal to 0mV by wiring a link between terminal 3 and terminal 4,
but keep the loadcell connected in addition to this link, as the display needs
to see a full bridge at its input
b. Measure the excitation voltage on terminals 1(-) and 6(+) and confirm that
it is between 9.5 and 10.5V DC. If it is less than 9.5V, remove the plug-in
connector and measure the voltage directly on pins 1 and 6 with the connec-
tor removed. If it is still less than 9.5V, and if the meter has not been pur-
posefully modified to give lower excitation, then there is most likely a fault
with the display and it should be returned to us for the attention of our QA
Manager, with a report of what you found, for repair.
c. Measure the sense voltage on terminals 2(-) and 5(+) and confirm that it is
between 4 and 10.5V DC. If it is not, please confirm that you have connected
terminal 1 to terminal 2 and terminal 5 to terminal 6, either at the meter end
of the loadcell cable or at the loadcell end.
d. Measure the voltage between terminal 2(-) and terminal 3(+) It should be
half of the voltage you measured in step 3. If it is not, there is most likely a
wiring error between the display and the loadcell, or the loadcell is faulty.
Check the wiring according to the installation instructions for the loadcell and
the display. If that appears to be correct, measure the resistance of the four
loadcell branches according to the loadcell manufacturer’s specifications.
e. If steps 1 to 4 were satisfactory, the problem may be caused by the scal-
ing being too sensitive. If you are happy to do so, it is a simple matter to reset
the display’s scaling to the factory default conditions. Put the lockout switch
off and press all 4 buttons together for around 3 seconds until the display
shows “dEFS n” press the UP button once so the display shows “dEFS Y”.
Now press the OK button and the display will be reset to factory defaults.
If still no success, please return the display to us for the attention of our QA
Manager, with a report of what you found, for repair.