Delta OHM HD2102.1, Manual

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THE PROBES
The instrument works with probes of the LP471… series: these are photometric and radiometric
probes that measure
illuminance (LP471 PHOT), irradiance (LP471 RAD, LP471 UVA, LP471
UVB and LP471 UVC), PAR (LP471 PAR) and luminance (LP471 LUM 2). All the probes, save
the LUM 2, are provided with a diffuser for cosine correction.
Upon turning on the instrument automatically detects the probe connected to the input: it is
sufficient to connect it. If the instrument is already on, turn it off and back on again in order for the
probe to be detected. The unit of measurement is determined according to the probe connected to
the input: In cases where more than one unit of measurement is provided for the same probe, use the
UNIT key to select the one desired.
All probes are calibrated in the factory; no calibration is required by the user.
In addition to instantaneous measurement the instrument calculates the acquired measurement time
integral Q(t). Some thresholds can be associated with the integrated measurement and with the
integration time, which can be set in the menu. When exceeded these thresholds cause the
instrument to stop the integral calculation.
The probe is detected during turn on, and this cannot be performed when the instrument is
already on, therefore if a probe is connected and the instrument is on, it is necessary to turn it
off and on
.
Q/T
IME INTEGRATION
In addition to instantaneous measurement the instrument calculates the following summation:
(1) Q(t) = u(t) t,
Σ
⋅Δ Δ
t = 1sec
0
t
where u(t) is the instantaneous value of the input variable compared to time t. The sampling interval
is fixed at 1 second.
As soon as either the Q(t) value or the integration time t reach the set limit, the integration is
stopped.
Maximum integration time: 100 hours, 00 minutes, 00 seconds
Integration interval: 1 second
How to set the limits
To set the integration limit, enter the " INTG LIMT ###S " menu item. Use the arrows to set the
desired value. Confirm by pressing ENTER.
To set the final integration time, enter the
TIME LIMT HOUR, TIME LIMT MIN and TIME
LIMT SEC menu items. Use the arrows to set the desired value in hours, minutes and seconds.
Confirm each item using ENTER.
To cancel the limit, set its value to 0.
How to perform an integration measurement
After setting the limits, as illustrated above, exit the menu and return to normal measurement.
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