YOKOGAWA 51011, Руководство пользователя

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IM 51011-01EN
33
Measuring
1.
While normal illuminance measurement or color correction
measurement is in progress, press COMP .
The comparator function is enabled, and [COMP, Lo],
[COMP, Hi], or [COMP, Go] is displayed.The automatic
power-off function is disabled, and [AUTO POWER OFF]
disappears.
2.
To view the high and low limits, hold down
CALL
.
The high and low limits are displayed alternately at
1.5 second intervals.
3.
To return to the normal illuminance measurement,
hold down
COMP
for at least 1 second.
[COMP, Lo], [COMP, Hi], or [COMP, Go] disappears.
12. Ripple Measurement (S-F Key)
This function is available on Model 51021.
The ripple measurement function facilitates the measurement of
indoor fluorescent lamps during the daytime.
When the illuminance of fluorescent lamps is measured with a lux
meter during the daytime, the sunlight influence is large.
A typical method to overcome this phenomenon is to measure
the fluorescent lamps with the sunlight first, measure the sunlight
without the fluorescent lamps (ambient light only) second, and
take the difference. However, this method requires you to turn on
and off the lamps at each measurement point, wait for the lamps
to stabilize each time they are turned on, and so forth.
In other words, this method takes trouble and time.
Another method is to measure all the measurement points first
with the fluorescent lamps turned on, then measure the same
points with the lamps turned off second, and then take
the differences. This method is disadvantageous in that taking
measurements at the same location and height when the lamps
are turned on and when they are turned off is difficult,
which results in errors.