Knauer Azura ECD 2.1, Инструкция по эксплуатации

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77 Rear panel I/O
AZURA® Detector ECD 2.1 Instructions, V6685
The maximum rating for these contact closure outputs are 24 VDC (swit-
ching voltage) and 0.25 A. The relays can be controlled in the Elite Dialo-
gue software and ClarityChrom® Chromatography software.
AUX
The ECD 2.1 has 4 free programmable TTL outputs AUX1 – AUX4 (pin
7 – 10). These contacts are default ‘high’ 3.3V (inactive), when active the
status is ‘low’ 0V.
Overload
The overload output (pin 11) can be used to monitor if the cell current
goes out of range during a chromatographic run. An ‘Out of range’ error
appears when the cell current Icell exceeds the limit of the current range
at which the measurement is performed (see Fig. 65).
Fig. 65 Example of a chromatogram were the cell current exceeds the maxi-
mum current level and the signal is ‘out of range’.
It is important to recognize an ‘out of range’ (overload) situation, be-
cause it may lead to erratic results when quantifying analyte concen-
trations in samples.
If for instance the cell current goes in out of range during the recording
of an analyte peak, it can be (in most cases) easily recognized by a flat top
of the peak and a very abrupt transition to the flat top at the edges.
By default the status of the overload output is ‘high’ 3.3V. When the cell
current has the status ‘out of range’ the overload output will change status
to ‘low’ 0 Volt, until the cell current returns to a value within the measure-
ment range again. The overload output (pin 11) is one of the configurable
I/O’s.