Metrohm 781 pH/Ion Meter - Manual (Page 146)

9.1 Technical data
136
780/781 pH/Ion Meter, Manual
9.1.3 Measuring input specifications
Measuring range Resolution Measuring accuracy 1)
pH –20.000...+20.000 0.001 pH ± 0.003 pH
Temperature
Pt1000
NTC
–150 °C...+250 °C
–20 °C...+250 °C
0.1 °C
0.1 °C
± 0.2 °C (Pt1000: –20 °C...
+150 °C)
Potential –2200 mV...+2200 mV 0.1 mV ± 0.2 mV
Concentration
(781 only)
1.0 ⋅ e -37 ... 1.0 ⋅ e 37 0.2 % 2) ± 0.4 % 2)
1 ) ±1 digit, without sensor error, under reference conditions
2 ) for single charged Ions
9.1.4 Interfaces
RS232 connection
RS232 Hardware and software handshake for printer and re-
mote control
MSB connections (MSB = Metrohm Serial Bus)
Stirrer Connection of max. 1 stirrer
Stirrer control: manual on/off, or automatic during
measuring sequence
Rate selectable in 15 steps
Remote box Connection of max. 1 remote box
Activation and control of external devices, e.g. sample
changer, Dosimat Plus (781: Conc mode)
Barcode / Keyboard connection
PC keyboard PS/2 PC keyboard
Barcode Barcode reader with PS/2 interface
9.1.5 Power supply
Power supply unit
Power consumption
12 V ±1%, 1A
5 W (without external loads)
The following current consumers are allowed:
Remote box with connection
Stirrer at MSB connection
Barcode / Keyboard
< 40 mA, 5 V
< 200 mA, 12 V
< 250 mA, 5 V