Hanna Instruments HI 9931 - Manual (Page 6)

6
FRONT PANEL
FUNCTIONAL DIAGRAM HI 9931 FUNCTIONAL DIAGRAM HI 9931 FUNCTIONAL DIAGRAM HI 9931 FUNCTIONAL DIAGRAM HI 9931 FUNCTIONAL DIAGRAM HI 9931
EC
0
1
2
ALARM
mA OUTPUT
4/20 0/20
mS
0
SECONDS mS
1.6 0
TIMER
MINUTES
90
45
FINE SLOPE
CAL
COARSE
PROPORTIONAL SETTINGS
ALARM AUTO
MANUAL
SET
READ
FERT.
SET POINT
HI 9931
1 10
2.5
5
7.5
0.8
mS
EC
FEED
ALARM
LINE
SET EC
ZERO
CAL
1
2
3
4
5
6
7
8
9
10
11 12
13
14
15
16
17
18
19
20
Left panel
1. Liquid Crystal Display
2. Slope calibration trimmer
3. Fine setpoint trimmer
4. Coarse setpoint trimmer
5. Zero calibration trimmer
6. Alarm LED warning signal
7. Alarm disable switch
8. READ for actual measurement and SET for setpoint
adjustment
9. Dosing LED signal
10. Proportional conductivity band setting
11. Proportional time cycle setting
12. Overdosage timer
Right panel
13. Conductivity alarm setting from 0 to 2.0 mS/cm (EC)
14. Recorder output contacts
15. 0 to 20 or 4 to 20 mA output selector
16. Triple contact alarm in a Normally Closed (NC) or a Normally
Open (NO) position.