user to set the range they will stay in during measurement.(see 15E below for informa on on seLng
the range.)
15E. Gain Range:
When Auto Gain Range is set to off in sec on D above, Gain Range becomes
accessible. The user can select the range based the max current to be measured. Ie; 1 mA, 3uA or 300
nA. Each relay allows the ILT2500 to measure approximately 3-4 decades with the max being the
satura on point and noise become problema c as the reading approaches .0005 from the max.
To determine the range of current that applies to a specific light level reading, the user can select
current in the display units (see sec on 14A for instruc ons)
or mul ply a previous reading by the
calibra on factor used to obtain the reading. Ie. 1mW/cm2 (1e-3 mW/cm2) with a calibra on factor of
1e-3 (A)(cm2)(W-1) =.000001 amps, 1e-3 * 1e-3.
15F. Min-Max (and FW Peak)
: The min-max seLngs allows the user to change the func onality of the
min-max bu3on.
When in Min/Max mode, the reading will only change for Max when a reading that is higher than the
displayed value is read, and for Min when a reading that is lower than the displayed value is read.
When FW peak is displayed the min-max bu3on will change to a FW Peak bu3on. FW Peak uses the
fastest scanning speeds to see rapid changes in light intensity and uses less averaging. For Very Fast
moving light sources such as scanning lasers or pulses of light, use FW peak. For be3er averaging we
recommend using min-max when speed is not a factor.
15G. 5V Bias On or Off:
The defaults seLng is off as there are numerous sensors that can be
damaged or read incorrectly if bias is applied. When turned on, the meter will supply reverse bias to
any sensor plugged into the device. (See sec on 5 for pin out informa on pertaining to bias)
Silicon sensors such as the SED033, SED100, SPD025Y, and the XRL series can be biased when
measuring flashing or rapidly changing values to increase response me. SED240, SED220 and SED185
Vacuum phototubes require the bias to be turned on to obtain the needed power.
WARNING: Sensors can provide inaccurate readings or be damaged if inadvertently biased. The ILT
SED005 (GaAsp), and SED623, SED624 and SED625 (thermopiles) should not be supplied with 5V bias.
Recording to File Se$ngs
15H. Recording Interval:
Ranges from 1 second to 1 hour, or sample for
faster speeds.
Sample: when selected, the record interval and sample me are synched.
Ie if sample me is set .1, the meter will record a value every .1 seconds.
Trend Chart Se$ngs
15I. Chart Type:
Select a bar graph or line graph
.
15J. Update Interval:
Select the me between updates to the display
from .1 sec to 1 hour.
Error and Warning Level SeLngs15K. Light Stack SeLng: SeLngs for light
stack will determine when the screen turns Red, Yellow, and Green.
Trigger Type: There are three available triggers to ini ate a change in the
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