The actual sensor value can be seen on the display rising or falling respectively. The magnets are the equivalent of
the PCB UP and DOWN push buttons.
LOW ALARM is the next menu and left and right magnets increase and decrease this value.
HIGH ALARM is next followed by OVER RANGE alarm.
The direction of the alarms is displayed as ^ for rising and v for falling but these can be changed using left and
right magnets together.
Appendix 1
Hyperterminal Display
OHLDFI
•
O
H
and
L
represent the Over Range, High and Low alarms respectively ^^v shows the direction of alarms
•
D
indicates if a duplicate address is detected
•
F
indicates a fault
•
I
indicates alarms inhibited
Pressing
(R)
when in normal runtime display causes a sensor reset to occur. Gas type with address and serial
number are then output to the PC together with alarms and calibration date, etc.
This also starts 1 minute autozero, which is useful when adjusting VR2 zero potentiometer.
Pressing
(C)
on the PC will list the available commands
(V)
Allows a view of the gas log taken at one minute intervals over 48 hours
(A)
To set the sensor address
(G)
Select gas type Select the gas type from a list
(Z)
Prompts to use the zero potentiometer
(S)
Prompts to use the PCB buttons
($)
Initialise the sensor
(%)
Clear the log of sensor readings, (this takes a minute to perform)
(U)
Alarm directions, Rising or falling
(D)
Enter calibration date
(R)
Enter the range of the gas x 10
(F)
Set 4mA level Use H and L and space
(T)
Set 20mA level Use H and L and space
(O) (H) (L)
Set over, high and low alarm levels x 10
(M)
Set the value of full range raw processor measurement value when maximum gas was applied
(E)
Allows the editing of the 8 character user gas description
(X)
Exit to normal display
