HT instruments HT8000 - Manual (Page 7)

HT8000
EN - 6
4.2. FUNCTION KEYS DESCRIPTION
4.2.1. POWER
key
Press the POWER key for switch on/off the instrument. The reference of the last selected
function is displayed.
4.2.2. INPUT/OUTPUT
key
Press the INPUT/OUTPUT key to select the mode of the measurement of the parameters
(INPUT) and the generation of signals (OUTPUT) performed by the instrument. The
“INPUT” or “OUTPUT” symbols are displayed.
CAUTION
The instrument DO NOT perform the simultaneous operations of
measurements (INPUT) and signals generation (OUTPUT)
4.2.3. V/mV
key
By means of this key is possible to select the measurement unit “mV” (100mV range) or
“V” (10V range) of DC voltage both for measurement (INPUT) and generation (OUTPUT)
operations
4.2.4. mA/%
key
By means of this key is possible to select the measurement unit “mA” (24mA range) or
“mA%” relative to the 0-24mA scale (-25%
 0mA, 0%  4mA, 100%  20mA, 125% 
24mA) of DC current both for measurement (INPUT) and generation (OUTPUT) operations.
4.2.5.
 and  arrow keys
The
 and  arrow keys, associated to each DC voltage and DC current generation,
permits respectively to increase or decrease the value set at display. The arrow keys in the
positions 9 and 10 of Fig. 1 permits to increase or decrease the value of the most
significant digits while the arrow keys in the positions 11 and 12 of Fig. 1 permits to
increase or decrease the value of the less significant digits in order to perform a fine adjust
of the value set at display. Press and hold of this keys to perform a fast set values
operation.
4.2.6. Deactivation of the Auto power off function
In order to preserve internal battery the instrument switches automatically off approx. 6
minutes after it was last used. When the instrument must be used for long periods of time,
it may be useful to deactivate the Auto Power Off function as follows:
1. Switch off the instrument
2. Keeping the INPUT/OUTPUT key pressed switch on the instrument by pressing the
POWER key. The symbol “APOno” appears at display for a while
3. Switch off and on again the instrument to automatically enable the function.