Technical -  Also see the H11-LIN Background -> SPECIFICATIONS NOTE: New test results showing this sensor's limits of response and radial symmetry should be available by January 2008. The results will be presented on this page.

The current model is the Model H11-LN. A new PHA (see link above) data output and selectable gain is now standard.  Particle count sensitivity has been dramatically increased over previous models.  The circuit board is now conformal coated virtually eliminating corrosion failure.

The cylindrical crystal is suspended between rubber mounts axially on a 2.54cm diameter stainless steel post.  The previous anodized shield that was glued on to the outer surface of the crystal has been eliminated.  The crystal surface is now nickel plated protecting it from impact damage and most importantly insures symmetrical radial response.

These sensors are designed to be completely wiring error safe. This means any wiring hookup errors caused by connecting any combination of wires of any polarity to 12VDC will not causing damage to the sensor electronics.  There are also 8 each, 20amp (100amp pulse) internal static lightning arrestors to protect against static charges produced by saltating particles and near lightning strikes.

The outputs are 1)number of particle impacts (or "PC", particle count), 2)kinetic energy (KE) are CMOS/TTL compatible pulses and, 3) the new PHA (pulse height analysis) output. See for more info.

A field data system that has pulse counting capability is required to record this type of data.  An alternative set of outputs is also provided for pulse width input to data loggers. The Particle Count output is straight forward. The KE pulse represents a fixed amount of kinetic energy.  This output has been empirically found to correlate to mass flux with a linearity r^2 => 0.997.

The following document has not been updated to include the new additional PHA data output but covers 90% of all technical issues. Please read the document for a detailed description of erosion site requirements and data acquisition.

The new model H11-LIN

Outputs:

Inputs:

Upgraded Model Number  - H11B  Wiring Hookup

NOTE:  New color code as of November 2006

The reason for the wire color change;  We used to use cable which had two large diameter wires and four small diameter wires. This forced the power (+12VDC and Ground) to be naturally be assigned to the larger diameter wires.  Unfortunately, these colors were black and white.  Now that all wires are the same diameter (and same color selection) we decided we must adhere to the conventional colors of red and black for power.

Outputs

Alternate outputs (seldom used)

Power

Original Model  - H11B - Standard Wiring Hookup

NOTE:  Original color code prior to November 2006

Outputs

Alternate outputs (seldom used)

Power

Data Processing and Calibration document - Main reference manual

The "Data Processing and Calibration" document contains theory of operation, catcher information and technical information about the wind eroding mass sensor.