Control Mode - Hanna Instruments pH500 Series Instruction Manual

CONTROL MODE

RELAY MODES
The control mode is the normal operational mode for these
meters. During control mode pH500 and mV600 fulfill the
following main tasks:
• convert information from pH/ORP and temperature inputs
to digital values;
• control relays and generate the analog outputs as deter-
mined by the setup configuration, display alarm condition;
• RS232 management.
In addition, pH500 and mV600 can log working data
through RS232 connection. This data includes:
• pH, mV and C measured values;
o
• last calibration data;
• setup configuration (also from PC).
The status of the meter is shown by the LED's on the right
STATUS
Control Alarm
OFF ---
ON OFF
ON ON
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
different modes:
1) ON/OFF, high setpoint (acid dosage);
2) ON/OFF, low setpoint (base dosage);
3) proportional, low setpoint (base dosage, if available);
4) proportional, high setpoint (acid dosage, if available).
Alarm LED (green) Relay LED (yellow) Red LED
ON
ON
OFF
LEDs
OFF ON
ON or OFF OFF
ON or OFF Blinking
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