9
Direct and Addressable Line text
The Combi system measures data on all active sensors.
Direct sensors are done sequentially but addressable sensors send their data periodically
when available (every few seconds).
Each sensor has a text description (stored on the main pcb, not in the sensor) which
describes physically where it is in the system and this text appears on the LCD as the
most recent measurement is displayed. Using the engineer’s menu, this text can be
altered from the default text to something more meaningful.
Editing this text is either manual using buttons and the LCD or by sending a text file from
the PC. The latter is much faster and is preferred. The manual mode is activated from
ENGINEER’S
menu 17 which presents the direct 4-20 channels text first followed by the
Addressable text.
Pressing
+ (4)
or
– (2)
changes which channel is to be altered and pressing
UP (1)
enters
the text editing mode for this channel. The
+ (4)
and
– (2)
buttons now move a cursor
under the text and
UP (1)
and
DOWN (5)
alter the character at this cursor position. When
editing is finished for this channel, press
SELECT (3)
to exit the editing which returns to
allow changes on another channel by pressing the
UP (1)
button again. Alternately
pressing
SELECT (3)
will exit the direct 4-20 channel text and enter the Addressable
channel text selection. Again the buttons are used in exactly the same way to change the
text description for networked Addressable sensors.
SELECT (3)
when pressed will exit the manual mode and save the text changes in non
volatile memory on the main PCB and return to the
ENGINEER’S
menu.
See also DATA to and from a PC using Hyper-terminal which allows a much quicker
method of editing using a PC.
Holding the Display
As the display cycles through the active sensors sequentially, it may be required to stop
on a particular channel for maintenance.
This can be achieved using the
+ (4)
button on the front panel which when pressed will
hold the current sample for 999 seconds. A countdown is displayed on the LCD showing
that hold is in progress. At the end of this time normal display sequencing will resume.
The gas values displayed on the LCD during hold are still the current live readings from
the sensors.
Hold can be removed at any time by pressing the
+ (4)
button for a second time.
As the sequence of display continues it is sometimes required for maintenance to choose
another sensor for display and this can be achieved using
UP (1)
.
This button when pressed terminates the current display it moves to the next displayed
channel and if pressed continuously, this button will step through all available sensors
When the desired channel is reached and the button released, press
+ (4)
to hold this
display for 999 seconds. Pressing
+ (4)
will release the system back to normal.
