The instructions for all the gauges are the same. The button shows stored maximums, and when pressed at power-on, puts the gauge into programming mode.
On the display you will see "bL on" -- backlight on. If you bump the button again, it will go to the next menu option. If you press and hold for two seconds, it will edit that option. To exit editing, power off the gauge (like me, you'll soon wish you'd wired in a power supply switch nearer the gauges). Once it's set up, you'll periodically do the reset peaks and zero pressure function, the rest you can forget about.
The External functions are for sending signals to something connected to the gauge, like a monitor or shutdown timer.
Menu options:
bL on/off - backlight on/off
rt PE - Reset Peaks (forget the stored maximums)
-- PE - Zero Pressure (reset current pressure to zero reference)
At - Average Time (period of time measurements are taken)
LP - Low Pressure setpoint (red light blinks when below this)
ELP - External Low Pressure setpoint
ot - Over Temp setpoint (amber light blinks when above this)
Eot - External Over Temp setpoint
EFL on/off - External FLash on/off
thr on/off - thermocouple option on or off (on for EGT probe)
Lb - low battery setpoint
Uni - set units for pressure (kg/cm2, PSI or BAR)
dEg - set units for temp (F or C)
rAn - pressure RANge (normally 16BAR sensor is supplied -- up to 232 PSI)
CAL - calibration mode (password protected)
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