HT instruments HT309 - Manual (Page 6)

HT309
EN - 5
4.2. DESCRIPTION OF FUNCTION KEYS
Some of the function keys on the front panel have a double function, which can be
activated by pressing and holding the key for more than 1 second.
4.2.1. HOLD/L.S. (Light Source) key
¾
Press the HOLD/L.S key to freeze the value of the measured quantity on the display.
The symbol “HOLD” appears on the display. Press the HOLD/L.S. key again to exit the
function.
¾
Press and hold the HOLD/L.S. key for more than 1 second to select the light source to
be measured. Proceed as follows:
1. On the sub-display, observe the flashing symbol “Lx”, where 0 < x < 9 indicates the
source number.
2. Use the arrow keys S or T to select the desired source among the available options
L0 ÷ L9 (see Table 1)
3. Press the HOLD/L.S. key to set a possible correction factor on the instrument’s reading
(only for custom sources L7, L8 and L9). The indication of the parameter value flashes
on the display. Use the arrow keys S or T to set (press and hold the keys for rapid
operation) the value between 0.001 and 1.999. The values of the sources L0 ÷ L5
cannot be modified.
Symbol on the
display
Source type Correction factor
L0 Standard light 1.000
L1 White LED 0.990
L2 Red LED 0.516
L3 Yellow LED 0.815
L4 Green LED 1.216
L5 Blue LED 1.475
L6 Purple LED 1.148
L7 Custom 1.000
L8 Custom 1.000
L9 Custom 1.000
Table 1: List of available sources
4. Press and hold the HOLD/L.S. key for more than 1 second to confirm the operation.
The symbols stop flashing on the display.
4.2.2. LX/FC/CD key
¾ Press the LX/FC/CD key to select the measuring unit of illuminance, choosing between
the two available options “LUX” and “FC” (1Fc = 10.764Lux ; 1Lux = 0.09290Fc).
¾
Press and hold the LX/FC/CD key for more than 1 second to select the measuring unit
of luminous intensity (see § 4.3.2).