LaserUser.com Forum (formerly RDWorksLab)

FWIW, the Ruida controller has several digital inputs including one for "water protect". (Others are for other safety inputs). If the incoming signal is not active (I forget if it's looking for Vcc or GND) then the controller software will not activate the laser. IIRC, the HV power supplies have an "Enable" and a "Power" input that come from the controller.

My point is that perhaps your DIY laser can do something like this and avoid having to relay the HV power supply.

I presume you are building your own flow sensor because you're interested in the challenge, and not because you're unaware that they exist and may be purchased.

You are 100% correct.
I have been looking at the 6442g.

The RDC6445G seem like the way to go if I decide to use their controller.

I have bought a number components for my build already. Ruida RDC6445 controller, DM556S stepper controllers and a few other components. The steppers and power supplies are next on my list. I'm thinking of running the steppers on 48v. Hence needing a 24v and a 48v power supply. Will use a buck converter to step down to 12v for case fans from 24v supply. I will use ac powered extraction fan system with relay control. I'm trying to buy the more expensive parts first before the trade war begins to bite.

I would like to buy a red dot laser and would like to find some Chinese sources with US outlets if possible. Any pointers appreciated.