PerkinElmer Wallac 1420, Руководство пользователя

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Flash Energy Area
There are two options for this parameter “Low” and “High”. The energy of the flash lamp
used is dependent on the discharge capacitor value. The “Low” Flash Energy Area selects a
basic capacitor of 10 nF. The “High” Flash Energy Area selects a second 10 nF capacitor in
the lamp’s discharge circuit thus doubling the energy. If you select "High" you will reduce
the counting time (number of flashes), but the counts will remain about the same.
Flash Energy Level
The Flash Energy Level sets the voltage of the discharge capacitor; the range is from 1 to
255 (corresponding to 500 to 800 volts). Note that although the lamp input energy depends
on the squared power of the discharge voltage, the output optical power is not linearly
dependent on the input energy. By changing this parameter you will fine-tune the Flash
Energy. If you increase the number, you will reduce counting time, but counts from your
sample will remain about the same.
CAUTION: If software version 2.0 release 8 or higher is installed on an instrument
having a serial number less than 4201396, then you should avoid the combination of
settings: Flash Energy Area = "High" and Flash Energy Level = high values (e.g.255)
along with 384-well or higher plates. The reason is that this "high power/continuous
usage" combination may damage the older type of flash lamp. The cooled flash excitation
system available for newer instruments is especially designed to cope with this.
Excitation Filter
The non-changeable filter in the flash excitation path., D340, has a maximum transmittance
at 340 nm and half-bandwidth of about 35 nm. The other two filters are only used for UV
absorbance.
Light Integration Capacitors
A reference circuit monitors the total excitation energy. When the selected total amount of
energy has been reached the flashes stop. The reference circuit makes use of three light
integration capacitors, numbered 1, 2 and 3, any one of which can be selected. The
capacitor selected determines the total excitation energy in the same proportions as the
capacitor numbers (within component tolerances). This means that selecting capacitor 2
instead of capacitor 1, approximately doubles the excitation energy for one measurement,
i.e. the number of flashes for one measurement doubles, hence the time used for one
measurement doubles and the number of counts doubles. Selecting capacitor 3 instead of
capacitor 1 triples the excitation energy, the measurement time and the number of counts.
The number of flashes can be seen from the result viewer by selecting
View all result data .