Sensor Head Mounting Summary - HID Lumidigm M Series Mechanical Integration Manual

Lumidigm M-Series M3xx Modules Mechanical Integration Guide, PLT-02217, Rev. A.0
Once the pressure set and compressive properties of the gasket material are determined,
the final design consideration is reviewing the overall design for part-to-part tolerances so
that when the M3xx is secured to the enclosure, the required minimum gasket pressure is
achieved for the loosest part-to-part stack up. In addition, the tightest part-to-part stack up
should not exceed the maximum pressure allowable on the M3xx sensor head platen with
respect to the M3xx sensor head mounting features of 18psi. Figure 10 provides an example
of a positive stop design using the mounting ring shown in Figure 9.
Figure 10: Example mounting, detail

3.3 Sensor Head Mounting Summary

The features that capture and hold the M3xx sensor head should be designed to reliably
achieve the customer-required solid and liquid intrusion ratings.
The area around the platen should not allow standing water to accumulate or provide areas
that trap dust and other debris. Tilting the platen surface to provide drainage should be
considered when the enclosure is placed outdoors and exposed to precipitation.
The design should make allowances for easy cleaning of the platen surface.
The mounting method should be a positive stop design so that the reliability of the seal is
independent of manufacturing technique.
Allowances for the connecting cables and strain relief of those cables must be considered.
Page 13 of 28 December 2014