Academics - Courses
Engineering 382 Instrumentation Projects
Snow Sensing
The system described herein detects and reports snow and/or ice on the roof of DeVries Hall. A self-heated senor plate adhered to a patio stone on the roof of DeVries Hall is designed to melt and detect snow or ice that accumulates on it (Figure 1).
Figure 1. Sensor on Roof of DeVries Hall
This moisture recognition is accomplished when the melted water functions as a closed switch to the printed circuit on the sensor face (Figure 2). However, no signal of moisture presence will be sent out until the ambient temperature is below 5 °C; then the temperature sensor, connected in series with the senor plate, will allow a moisture signal to be transmitted (Figure 2).
Figure 2. Sensor Unit
This signal then goes to the system junction box in the DeVries Hall Penthouse which causes a solid state relay to close (Figure 3).
Figure 3. Junction Box and FieldPoint Module
The closing of this relay (switch) sends a 24 [mV] signal to a FieldPoint
Module which indicates to LabVIEW, a software package, that snow or
ice is present on the roof of Devries Hall. With this information LabVIEW
will then turn on a pump that circulates a Glycol/H2O solution through
a snow melt loop under the patio stones (See
Solar Thermal). Consequently, if the temperature rises above 5 °C,
or moisture is no longer detected below this point the relay opens which
corresponds to a 0[mV] signal sent to the FieldPoint Module alerting
LabVIEW that snow or ice are not present and in due course disengaging
the pump.
To see if snow or ice is currently detected please click on this link and look to the bottom left portion of the screen: Snow Detection.
Snow and Ice Sensing System
Engineering 382 Design Project – Spring 2005
Matt Scholten - Jeff Blech - David Allen - Chris Wiesehan
Author - David Allen
