Detcon 840 - Manual (Page 16)

840 Operators Manual
Model 840 Operator Manual Rev. 1.9 Page 12 of 29
NOTE: The controller automatically times out of Menu Mode and returns to the Main Display after 1
minute of inactivity.
6.4 Main Display Functions
The Main Display is a 1¼”x 6” backlit LCD that has 4 lines by 40 characters. In normal operation “CH # =
XX ppm GAS” will be displayed. If any channel is in any gas alarm condition, the “CH#” will change to
“ALM”. If any gas channels are in Fault, they will display “CH # = IN FAULT”. If any channels are in
CAL MODE, they will display as “CH # = IN CAL”. If any channels are not communicating with sensors
set up as serial input sensors, then they will display as “CH # = NO COMM”.
NOTE: The LCD has a backlight that will automatically turn off after 30 seconds of inactivity. The LCD
backlight will come on automatically as soon as any function key is pressed. This is a feature designed to
save on power.
6.5 User-Interface Menu Functions
The User-Interface is conducted via the Model 840-N4X Front Plate (Figure 8). The Menu Flow Chart
(Figure 9) is navigated using the function keys described in Figure 8. User-Interface menu activity is
conducted via the 1”x5” LCD and the four function keys. Four LED indicators on the front panel show
alarm and fault relay status. The LED’s represent ALM 1 (green), ALM 2 (amber), ALM 3 (red) and
FAULT (blue). There are 13 Main Menu entries and their functional descriptions are discussed below.