Control Mode - Hanna Instruments HI 23 Series Instruction Manual

CONTROL MODE

RELAY MODES
The control mode is the normal operational mode for these
meters. During control mode the meter fulfills the following
main tasks:
• converts information from EC/TDS and temperature in-
puts to digital values;
• control relays and generates the analog outputs as de-
termined by the setup configuration, displays alarm
condition;
In the HI 24 series it is possible to switch between EC and
TDS reading pressing "LCD". The TDS value is obtained mul-
tiplying the EC measurement by the TDS factor set through
setup. The HI 23 series displays EC only.
The status of the meter is shown by the LEDs.
STATUS
Control Alarm
OFF ----
ON OFF
ON ON
The meter exits control mode by pressing SETUP or CAL and
confirming the password. Note
that this command generates
a temporary exit. To deactivate
the control mode definitively,
set CONTROL ENABLE to "0"
(item # 02).
Once enabled, the relays 1 and 2 can be used in four differ-
ent modes):
1) ON/OFF, high setpoint (low conductivity dosage);
2) ON/OFF, low setpoint (high conductivity dosage);
3) PID, low setpoint (low conductivity dosage, if available);
4) PID, high setpoint (high conductivity dosage, if available).
LEDs
Green LED Contacts LED (yellow)
ON OFF
ON ON or OFF
OFF ON or OFF
Red LED
ON
OFF
Blinking
21