Pressure Vs Time Plot for Dwyer MPR1-1 Pressure Regulator with Lunt Double Stack Solar Telescope

This plot shows the results of an experiment to assess the utility of the Dwyer MPR1-1 miniature pressure regulator for use in remote pressure tuning the etalons on a Lunt solar telescope. Using a supply pressure of 50 PSI from an ordinary 6-gallon oil-free air compressor with inline desiccant filter, I used the Dwyer pressure regulator to reduce and control the pressure applied to the two etalons of a Lunt LS80THa double stack solar telescope. A tee was used to apply a common pressure to both etalons using a 3D-printed replacement plunger available on Thingiverse in each pressure tuning knob. The experiment was conducted indoors in an airconditioned room at a temperature of 72F. Starting at zero gauge pressure, the dial on the pressure regulator was rotated until a pressure of 11.58 PSI was output (a typical pressure for getting on band). The output pressure was recorded at 2 minute intervals for a little over 6.5 hours. The resulting plot shows that the pressure was regulated to within about +/- 0.25 PSI over the entire period. This regulation seems to be entirely satisfactory for keeping the solar image on band over a long period of time, as would be required for time lapse photography of the Sun. In the future, I will test the telescope outside under the Sun, where the temperature will not be controlled.