REAR PANEL CONNECTIONS
Terminals #1: Probe
• Connect the supplied
HI3314
probe by following the wires
colour indications.
Terminals #2: Power Supply
• Model
BL983314-0:
connect the 2 wires of a 12 Vdc
power adapter to the ter12 Vdc and GND.
• Model
BL983314-1:
connect a 3-wire power cable to the
terminals while paying attention to the correct earth (PE),
line (L) and neutral (N1 for 115 V or N2 for 230 V) contacts.
Terminals #3: Dosing Contact
• This contact drives the dosing system, accordingly to the
selected setpoint.
Note
: The setpoint has a typical hysteresis value comparable
to the meter accuracy.
Terminals #4: Not Used Contact
Overtime system: jumper (#5) and trimmer (#6)
• This system allows the user to set a maximum dosing
period, by adjusting the rear trimmer from 5 (min) to
approx. 30 (max) minutes.
• When the set time is exceeded, any dosing action stops,
the LED indicator on the front panel will blink Red and the
LCD will show the “TIMEOUT” warning message. To exit
the overtime condition, set the OFF/Auto/ON switch to
“OFF” position, and then to “Auto” again.
• For disabling the overtime feature, simply remove the
jumper on the rear panel.
Note:
The overtime system works only if the OFF/Auto/ON
switch is in “Auto” position.
OPERATING THE METER
Attach the resistivity probe to the meter and immerse it in
the solution to be monitored while making sure that the
metal pins are completely submerged.
Press the “MEAS” key (if necessary) and wait for a few
seconds to allow stabilization of reading.
The LCD will display the resistivity value of the solution in
M
Ω
/cm unit. The LED indicator will light up Green when the
meter is in measurement mode and dosing is not active,
while will light up Orange/Yellow for signaling that a dosing
action is in progress.
FUNCTIONAL DESCRIPTION
Front panel
Rear panel
1. TC jumper for selection of temperature coefficient (
β
)
2. Connections for
HI 3314
resistivity probe
3. Power supply terminal:
• for
BL983314-0
model: 12 Vdc adapter
• for
BL983314-1
model: 115 Vac or 230 Vac option
4. This contact acts as a switch for driving the dosing system (e.g.
dosing pump)
5. Not used contact
6. Jumper for enabling (jumper in) or disabling (jumper
removed) the overtime control
7. Trimmer for overtime setting (typically from 5 to 30 minutes)
1. Liquid Crystal Display
2. Switch for selecting dosing mode:
• OFF = dosing disabled
• Auto = automatic dosage, depending on setpoint value
• ON = dosing always active
3. “MEAS” key to set the instrument to measurement mode
4. “SET” key to display and set the setpoint value
5. “SET” trimmer to adjust the setpoint value
6. 3-colour LED indicator:
• Green = meter in measurement mode
• Orange/Yellow = dosing in progress
• Red, blinking = indicates an alarm condition
OPERATIONS
CALIBRATION
The meter is factory calibrated.
If recalibration is needed, please contact your dealer or the
nearest Hanna Service Center.
SETPOINT
Press the “SET” key: the display will show the default or
previously adjusted value, together with the “SET” indication.
Using a small screwdriver adjust the “SET” trimmer until the
desired setpoint value is displayed.
After 1 minute the meter automatically returns to the normal
mode; or press the “MEAS” key.
SELECTING TEMPERATURE COEFFICIENT
The reading is automatically corrected for temperature varia-
tions by using the linear compensation method:
R
25
=R
t
(1+
β
(t-25))
where R
t
is the resistivity at the temperature t.
The reference temperature is 25ºC.
The coefficient
β
is user-selectable through the “TC” jumper on
the rear panel.
Three values are available: 2.4, 3.5 or 4.5%/ºC.
Follow the below diagram to set the desired coefficient.
Note:
If the coefficient 4.5%/ºC is selected, a minimum
measurement temperature of 10ºC is suggested to
maintain the best accuracy of the meter.
ISTBL3314R2 04/05
All external cables connected to the rear panel
should end with cable lugs.
A circuit breaker (rated 6A max.) must be
connected in close proximity to the equip-
ment, and in a position easy to reach by the
operator, for disconnection of the instrument
and of all the devices connected to the relays.