Hanna Instruments HI 250 - Manual (Page 4)

4
1) Liquid Crystal Display (LCD).
2) CFM/GLP key, to confirm different values or to display Good Laboratory
Practice information.
3) CAL key, to enter and exit/escape calibration mode.
4) /ºC key, to manually decrease temperature value or other parameters.
5) /ºC key, to manually increase temperature value or other parameters.
6) RCL key, to enter/exit recall mode.
7) LOG key, to store measured data.
8) SET/CLR key, to enter/exit setup mode, clear pH calibration or delete
logged data.
9) RANGE key, to select measurement range (HI 251 only) or to switch
focused data.
10) ON/OFF switch.
11) Power supply socket.
12) BNC electrode connector.
13) Electrode reference socket.
14) Temperature probe socket.
15) RS232 serial communication connector.
FUNCTIONAL DESCRIPTION
Front Panel Primary LCD
Secondary LCD
1
9 3
2
7
4
6
5
10
8
POWER
12VDC
INPUT
REF
TEMP
11 12 13 14
Rear Panel
C
CAL
CFM
READY 1
2
3
BUF WRONG
LOG mV pH TIME % DATE INTV
BUFFER pH
RS232
15
Functions pH Calibration - 3 points
RCL LOG
CLR
SET C C
RANGE
GLP
CFM CAL
pH / ORP Meter
HI 251
Confirm Calibration
in selected pH Buffer CFM
Select pH Buffer /
Start/Exit Calibration CAL
Select pH/ORP/ mV
Scroll Log Data
Rel RANGE
GLP Show GLP Data
LOG Store Log Data
SET/CLR Set Instrument Parameters
Clear Calibration/Log Data
RCL Recall Log Data