4 - 5
The Hand-held Keypad
The keypad contains eight membrane switches and a single LED indicator. The switches
provide four function keys (marked F1 to F4) arranged below the screen and a quadrant of
four control keys arranged around the LED.
The function keys
The operation of the function keys is context dependant. A menu bar, containing labels
for each of the keys, appears at the bottom of the screen. The labels for each function key
change to indicate the function (PAGE, EDIT, etc.) in the particular context.
The quadrant keys
The four quadrant keys are used to make adjustments, to apply or reject a load, or to start
an automatic test sequence if one is configured.
The
+ and – keys are used to increase or decrease values that are highlighted or displayed
on screen.
Pressing
I applies load if in Manual Test mode, or starts an automatic test if in Automatic
Test Mode.
If a load is already applied pressing
I forces the Hand-held to carry out a load correction
(that is to say that it will adjust the number of load elements applied to correct for changes
in voltage or temperature, etc.).
Pressing
O at any time will reject the load or abort any automatic load test that is running.
If the load is set to ramp down on reject (indicated by fast blinking of the green LED)
pressing
O a second time will drop the remaining load immediately.
The LED status lamp
The LED indicator provides feedback of the current load status:
Continuously On.
Load applied (manual mode) or test sequence paused (automatic mode)
Half Second Blink.
Automatic test running
Rapid blinking.
Ramping down on reject
Chapter Four
