System Error Relay - Hanna Instruments PCA 311 Instruction Manual

Alarm Relay
Note:

System Error Relay

Note:
Bromine Dosing Relay
RS485
Note:
2 4
A system alarm feature provides relay activation
to signal that the measuring value exceed the
alarm setpoints. The alarm relay is closed
(Common connect to Normal Close) if the value
is lower than alarm low setpoint or higher than
alarm high setpoint.
The ALARM LED blinks when alarm is active.
The Alarm relay is power-fail safe and is closed when the
analyzer is not powered.
A system error feature provides relay activation to
signal the need for operator intervention through an
external device, such as a buzzer, a light or any
other electrical equipment. When errors appears, the
relay is closed (Common connect to Normal Close).
The SYSERR LED blinks when a system error occurred.
If the situation persists for more than a few samples, the
operator should notify maintenance personnel for investigation
of the problem.
When the meter is in alarm mode or in system error mode, the user
could directly view the alarm or error description on the display.
If GSM transmitter is installed and GSM mode is selected, the
alarms and errors are sent as SMS message.
The System error relay is power-fail safe and is closed when
the analyzer is not powered.
The bromine dosing relay is activated (Common
connected to Normal Open) when bromine
concentration is under the dosing setpoint. The
bromine dosing use a proportional algorithm that
depends on both, setpoint and delta.
The analyzer has RS485 serial communication
with selectable baud rate between 1200 and 9600
Bps. The GSM module HI 504900 is also con-
nected using the RS485 port.
The RS485 could use also the ground wire to
prevent common mode voltages.
The DOSING BROMINE LED is turned on when the dosing
relay is closed.
ALARM
C NO NC
SYSTEM SYSTEM
ERROR ERROR
C NC
RS 485 RS 485
B I
A