EEPS? Model 3090 spectrometers now come standard with four configurable analog outputs. These
analog outputs offer users a convenient way to incorporate particle emission measurements into the
dynamometer host data collection system.
Each analog output operates independently, and is configurable for size range, weighting and
concentration range using a linear or log scale output.
→Size Range: Adjustable, single channel output only up to full range (5.6nm – 562.3nm)
→Weighting: Number, Surface Area, Volume, Mass, Custom
→Concentration: Concentration (dN), Normalized Concentration (dN/dlogDp)
An example where a user might be interested to set a defined size range would be to output
measurements of either the accumulation mode particles (i.e., soot) or the nucleation mode particles
(SOF). Spin buttons in the software make it easy to select standard EEPS? spectromenter channel
boundaries, or specific sizes can be entered.
The calculations for determining the output voltages for any choice of setting are based on the formulas
shown below. The concentration calculation is based on summed concentrations in each EEPS?
spectrometer size channel (or portion of a size channel) to cover the total size range multiplied by a
diameter weighting (diameter to some power) and multiplied by appropriate constants for the selected
weighting and other settings: