Knauer Azura ECD 2.1, Instructions Manual

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75 Rear panel I/O
AZURA® Detector ECD 2.1 Instructions, V6685
Ic (nA) = Vout (mV) x Range setting (nA)
1000 mV
So for example a signal on the output of 250 mV in the 200 nA range cor-
responds with an actual cell current of (250/1000)*200 nA = 50 nA.
I/E output
The I/E output is the unprocessed analog signal from the I/E converter
circuit. This signal is a true analog signal which is as close as practically
possible to the working electrode (WE). The maximum output voltage of
the I/E output is +/- 2.5V under all conditions and is independent of the
detector range setting. The signal in mV is related to the selectable I/E re-
sistor of 100M, 10M, 1M, 100K or 1K in the I/E converter circuit. The actual
cell current can be calculated from the analog I/E output in Volt using the
following formula:
Ic (Ampere) = Vout (Volt)
RI/E (Ohm) x 10
So for example an I/E output signal of 250 mV in the 5 nA range (RI/E
= 10 MΩ) corresponds to an actual cell current of 0.25V/(10 x 1E7Ω) =
2.5E-9A = 2.5 nA. In the table below, the I/E resistor value is listed for
every range setting.
Table VI. ECD 2.1 I/E converter resistors:
Current Ranges I/E Resistor (Ohm)
10pA, 20pA, 50pA, 100pA, 200pA, 500pA
and 1nA
100M
2nA, 5nA 10M
10nA, 20nA, 50nA 1M
100nA, 200nA, 500nA, 1µA, 2µA 100K
5µA, 10µA, 20µA, 50µA, 100µA, 200µA 1k
In the detector accessory kit a dedicated Output cable, D9 male – open,
2m (pn 250.0128A) is supplied. It is advised to use this manufacturer-sup-
plied cable for this type of measurements.