I'm in the process of running 120/240 VAC power as well as low-voltage
> signal wiring to an underfloor grid in the crawlspace under my
> workshop. I'm tired of tripping over power cables laying on the floor
> (I'm a klutz- I admit it) and decided to go ahead with the low-voltage
> signal wires when I took care of the power distribution. The signal
> wiring is for a DC control system similar to that designed and
> described by Robert Reed in Issue 91 (Feb, 2005) of Woodwork Magazine
>
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>
> That DC control system is designed to sense the current flow and
> automatically turn on the DC when a power tool is turned on. (See the
> article referenced above for details.) That is all well and good, but
> I'm somewhat lazy as well as being klutzy and would like the DC blast
> gate to be automatically actuated as well. Of course, that requires
> some kind of actuator.
>
> I'm aware of the EcoGate line of DC products which looks pretty good
>
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But, the MSRP of $85/4",
> $149/5", and $248/6" makes me want to investigate other possibilities.
> Especially since I've tried to follow Bill Pentz's advice and used 6"
> S&D piping
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$248
> per gate has a pretty high shudder factor. I'm perfectly willing to
> invest sweat-equity to bring the out-of-pocket expense down to a lower > value.
Had this in the back of my mind, when the blast gate is opened, a window type burglar alarm sensor opens or closes, (haven't thought that far yet) a circut to a relay to start the DC. Window sensors are a few bucks each, relay 25/30$ Close the blast gate, DC shuts down.