10
pH
0
1
2
0
100
200
mV
ALARM
pH
0
SECONDS
mV
200
0
TIMER
MINUTES
90
PROPORTIONAL SETTINGS
1
10
2.5
5
7.5
0
SECONDS
pH
2.0
0
TIMER
MINUTES
90
PROPORTIONAL SETTINGS
1
10
2.5
5
7.5
500
900
CAL
ALARM
ON
OFF
SET
FEED
mV
OFFSET SLOPE
ALARM
ON
OFF
0.5 1.5
pH
HI 9912
mV
ORP
ALARM
8
SET
FEED
ALARM
6
7
ACID
OXID
700
50 150
SET pH
SET ORP
ALARM
LINE
BL DOSING
PUMPS
pH
0
1
2
0
100
200
mV
ALARM
Diagram) and
remove the jumpersremove the jumpers
remove the jumpersremove the jumpers
remove the jumpers shorting the matching
pin terminals.
• When using a separate probe for grounding purposes, wire it to
the Matching Pin terminals on the right hand panel and
remove the jumpersremove the jumpers
remove the jumpersremove the jumpers
remove the jumpers (see 14 and 15 - Functional Diagram).
NOTE:
NEVER leave the jumper in when
using an electrode with a match-
ing pin. This can shorten the life
of the electrode (reference) drasti-
cally.
ALARM CONNECTIONS
• The operator can select an alarm threshold of 0.0
to 2.0 pH and 0 to 200 mV by turning the alarm
knob (see 13 and 16 of Functional Diagram). 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.
RELAY CONNECTIONS
• Wire the external devices (pumps or electrovalves) directly to the
relay terminal strips of the controller (see 18 and 19 - Functional
Diagram). The
terminals areterminals are
terminals areterminals are
terminals are
poweredpowered
poweredpowered
powered and
hence you
do not do not
do not do not
do not
need an ex-need an ex-
need an ex-need an ex-
need an ex-
ternal powerternal power
ternal powerternal power
ternal power
supplysupply
supplysupply
supply for the
pumps or valves.
NOTE:
HI 9912 provides for two separate relays, one for pH and another for
ORP. In order to save on chemicals and due to the slow reaction of
oxidants, the controller incorporates a
Consent featureConsent feature
Consent featureConsent feature
Consent feature by which
ORP measurements are adjusted only after pH has been corrected.
The Consent feature makes the
pH correctionpH correction
pH correctionpH correction
pH correction the
mastermaster
mastermaster
master and the
ORP adjustmentORP adjustment
ORP adjustmentORP adjustment
ORP adjustment the
salvesalve
salvesalve
salve for a better control.
REMOVE WHEN
USING MATCHING PIN
