Alarm connections, Feed slope cal zero cal – Hanna Instruments HI 9931 User Manual
Page 13
13
SET EC
ALARM
LINE
BL DOSING PUMP
0
SECONDS
mS
1.6
0
TIMER
MINUTES
90
45
FINE
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
SLOPE
CAL
ZERO
CAL
EC
0
1
2
ALARM
mA OUTPUT
4/20
0/20
mS
gram). The terminals are powered
terminals are powered
terminals are powered
terminals are powered
terminals are powered and hence you do not
do not
do not
do not
do not
need an external power supply
need an external power supply
need an external power supply
need an external power supply
need an external power supply for the pumps or valves.
ALARM CONNECTIONS
• The operator can select an alarm thresh-
old of 0.0 to 2.0 mS/cm for HI 9931
and 0 to 400 ppm for HI 9934 by
turning the alarm knob (see 13 -
Functional Diagram). If the actual mea-
surements are above the setpoint by a
margin greater than the user-select-
able alarm threshold, the alarm terminal is activated.
The alarm can be selected as normally closed ("NC") by connecting
the external device to the C and NC terminals or normally open
("NO") by connecting the external device to the C and NO
terminals.
• When activated, the alarm contacts will open or close, triggering
the mechanism of your choice. When the alarm is activated
alarm is activated
alarm is activated
alarm is activated
alarm is activated
all other terminals
all other terminals
all other terminals
all other terminals
all other terminals (such as dosing relay etc.) are
are
are
are
are
disactivated
disactivated
disactivated
disactivated
disactivated. The alarm LED light also comes on.
• The alarm AUTO/MANUAL switch (see 7 - Functional Diagram) is
only to disable the alarm terminal
disable the alarm terminal
disable the alarm terminal
disable the alarm terminal
disable the alarm terminal (e.g. the
buzzer will not sound). However, all other functions
such as disactivation of the dosing relay remain
unvaried, i.e. the pump ceases to dose until the
alarm condition is alleviated.
EC
0
1
2
ALARM
mA OUTPUT
4/20
0/20
mS
TDS
0
200
400
ALARM
mA OUTPUT
4/20
0/20
ppm
SET EC
ALARM
LINE
0
SECONDS
mS
1.6
0
TIMER
MINUTES
90
45
FINE
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
SLOPE
CAL
ZERO
CAL
EC
0
1
2
ALARM
mA OUTPUT
4/20
0/20
mS
EXTERNAL ELECTRICAL
DEVICE ACTIVATED BY
AN ALARM CONDITION
ALARM
AUTO
MANUAL