Instrument Type:
Optical detector
Related Commands:
Description:
Detector lamps are subject to aging. The LampIntensity command allows you to check the intensity of the lamp via the Log command. The value indicates the quality of the lamp. After you have installed a new lamp, periodically check the lamp intensity via the Log command, and then compare the two values. Note that for some PDA detectors, LampIntensity is the command for the UV lamp and VisLampIntensity the command for the visible lamp.
Function:
The Log LampIntensity command logs the lamp intensity for an optical detector in the Audit Trail, indicating the value in counts/second. The intensity of the lamp is checked at 254 nm at the retention time when the command is performed.
Tip:
Determine the lamp intensity at a time when it is not affected by substances in the flow cell. Therefore, it makes sense to check the value at the beginning of data acquisition.
Tips:
The lamp intensity can be included in the report. Select the LampIntensity variable from the Audit Trail category.
If you check the lamp intensity while recording the chromatogram, you have to a) search for the retention time at which the intensity was read (done automatically) or b) indicate it manually.
a) Type the end retention time of the chromatogram in the Formula field. For example, for an overall run time of 15 minutes, type
AUDIT.LampIntensity(15.0)
Chromeleon will automatically search for the retention time (backwards from the end retention time on) at which the lamp intensity was checked, and then indicate the lamp intensity that was measured at that time.
Or, you may search for the retention time at which the lamp intensity was checked from the data acquisition start:
AUDIT.LampIntensity(0.0,"forward").
b) If you know the retention time at which the intensity was checked, enter the exact time. For example, if the lamp intensity was read at 0.5 min, type
AUDIT.LampIntensity(0.5)