by SharpeCreations » Sun Nov 14, 2010 8:33 pm
I would like to get my hands on a small, inline flow switch to serve as an interlock, protecting the laser tube from loss of flow. I have done a good deal of searching for such a thing, and all I find are industrial units for big$$, and PC cooling stuff that outputs a pulse per rev signal (acting as a flow METER). I currently have a spinning-ball flow sight in the return line, which for all practical purposes, serves just fine, although a bit restrictive to flow.
One approach I may try, is to use a Dwyer low pressure switch, similar to what is used in furnaces to verify operation of combustion blowers. I would tee the switch into the pump discharge hose, where it would close a set of contacts once the pump starts to build a little pressure. The big flaw in this plan is that it only verifies presence of pressure, not flow. If a line were kinked, and not flowing, the switch would still signal an OK condition. I am not worried about a kinked line as much as a pump failure, which the pressure switch would detect. I think I will give this a try, as I have a switch I could try out.
Ideally, I would like to find a small, cheap, inline flow switch to protect the laser tube. Has anyone found a source?
Thanks in advance!