Metrohm 791 VA Detector - Manual (Page 31)

3.3 Operating element functions
791 VA Detector
25
Overload display
overload If the electronic current measuring circuit is overloaded, the red
light 2 is lit up (see Fig. 1).
Remedies
Select a less sensitive current range with adjusting knob 8
or compensate current with potentiometer 9 and/or 10 (for
further measures see section 4.3).
Polarization voltage
10 mV
Upol
0 1 5 +
The detection voltage U
pol
is set using the digital switch 11 (see
Fig. 1).
Setting range –1990 … 0 … +1990 mV
Resolution 10 mV
Current measuring sensitivity
4
nA
5
1
10
50
1
5
0,1
0,5 100
10
0,5
0,1
(U = 1 V) out
A µ
I
The sensitivity of current measurement is set using adjusting
knob 8 (see Fig. 1). The set range applies to the full-scale
deflection of the analog signal at sockets 22 and 23 (1 V or
10 mV depending on the setting of switch 21).
Setting ranges 0.1, 0.5, 1, 5, 10, 50 nA
0.1, 0.5, 1, 5, 100, 10'000 µ A
Polarity of analog output
The polarity (+ or –) of the analog output signal is set using
switch 20 (see Fig. 2).
Full-scale deflection of analog output
0...10 mV
0...1 V The full-scale deflection (1 V or 10 mV) of the analog output
signal is set using switch 21 (see Fig. 2).