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between these two times for it to be counted. It is specified approximately
in microseconds.
Difference
: not used.
Pressure
: reads the ambient pressure in kPa.
Temperature
: reads the case temperature in K.
I/O port
: should be set to COM1
Trigger Threshold
: this is a very important and somewhat subtle
parameter. It specifies the smallest signal voltage (in Volts on G3) that
will register as a particle. It is like the lowest threshold on a typical
instrument, in that events that are smaller than this signal size will not
initiate a count. Everything above this signal size will initiate a count (as
long as it satisfies the timing criteria). However, in this instrument, the
trigger threshold may not have anything to do with the lowest selected bin.
For example, the trigger threshold might be set to 0.100 V with this signal
size representing a 55 nm particle. The user can select a lowest bin of 60
nm, so that some triggers (particles between 55 and 60 nm) will not appear
as counts (they will appear in the underflow bin if selected). Or, the user
could select a lowest bin of 50 to 54.9 nm. No counts will appear in this
bin, since the trigger threshold is set to a signal size corresponding to a 55
nm particle.
Optical Block Pot
: not used.
Vref
: should be 10000 mV
Offset
: allows user to specify a voltage offset in the electronics chain of
the highest gain channel (G3). It is typically a few mV and should not be
important.
Purge coefficients
: conversion coefficients for the purge flow sensor.
Sheath coefficients
: conversion coefficients for the sheath flow sensor.
Sample coefficients
: conversion coefficients for the sample flow sensor.
Sample set coefficients
: conversion coefficients for the sample flow valve
Calibration
Tab:
