automatically controlling vacuum when cut motor is running

[Jrdarrah]

I finished a downdraft dust collector and air blast for my CW. I'd like to have them on only when the cut motor is running. Has anyone figured a good way to do that?

[Steven Alford]

If you connect your air blast to the out put of the cut motor (that exhaust dust bag on the back of the machine) it well then work when you have the cut motor on. But as for your dust collector, not sure about that one.

[roughcut]

If you connect your air blast to the out put of the cut motor (that exhaust dust bag on the back of the machine) it well then work when you have the cut motor on. But as for your dust collector, not sure about that one.

You could also have a pressure switch connected to the out put it could make a contactor to turn on the dust collector

[Digitalwoodshop]

I have this wired... Check out this switch.

http://www.rockler.com/product.cfm?page=17351

You plug your router OR CW into this box and when you turn on your router this box see's the current increase and turns on the bottom receptacle. You plug your vacuum cleaner into the bottom plug and now the vacuum cleaner turns on with the router and OFF with the router..... Pretty COOL.....

Does it work with the CW.... Your darn right it does.... I tried it.....

While measuring the board the vacuum stays off, as soon as the cut motor starts the vacuum starts.... Cut Motor OFF... Vacuum OFF......

The weakness with this I Switch is the Transistor or SCR used to turn on or off the Vacuum.... Draw TOO much current and it will FAIL....

My answer to this is to buy a Wall Wort AC Adaptor... You know the cube thing that turns AC Voltage into DC Voltage....

Plug the Wall Wort into the Vacuum Plug and the I Switch will last for YEARS.... The Wall Wort then operates a DC Relay that you wire to turn on and off your vacuum.... In my case, it will operate a relay that will turn on and off a 220 Volt Dust Collector. Finding the proper relay to switch the dust collector is easy on eBay. Lots of electrical relays in surplus.

In my case I have a 115 VAC to 24 Volts AC transformer and a few Power Relays that operate on 24 Volts AC.

This way when the machine stops for bit change, the blower stops...

AL:mrgreen:

[HighTechOkie]

Pretty slick Al. I like this approach since it also allows you to run the dust collector on a different circuit then the CW and I-socket are on.

Why not just use one SCR off the cut motor though rather than piggybacking them?

Rob

[HighTechOkie]

I highly advise NOT to use an extension cord connected to the cut motor. You WILL fry the power supply ($85+). A relay is much safer approach. Keep in mind, relays do fail/wear out. It is best to locate it outside of the machine.

After thinking about it a little more, Al's I-socket/wall wart/relay approach is probably the best and safest. No point in risking $100s to save $40 or so.

Rob

[Digitalwoodshop]

Pretty slick Al. I like this approach since it also allows you to run the dust collector on a different circuit then the CW and I-socket are on.

Why not just use one SCR off the cut motor though rather than piggybacking them?

Rob

Because the Cut Motor runs at different speeds it is computer controlled. Adding a 115 volt relay in parallel with the cut motor was my first idea but then you change the motor impedance. It's not by much, but it does make a difference. I asked Tech Support about it last year and they said NOT to do that....

The I switch is the ticket.... That way it controls a dust collector and air blast from another 115 VAC Circuit.

And NO you should never use use an extension cord with the CW. The voltage drop in a 16 gage cord will make the power supply work harder to make up on the loss of line voltage. That is when they can fail.

Relays last YEARS.... I would not worry about a relay failing.... In 30 years in electronics and Factory Automation using hundreds of relays, I have only seen 2 relay failures... One was on a 30 year old Navy Warship on a ventilation controller and the other at Sony a loose screw on the power wire got hot as the motor ran and melted the plastic case. They had a company come in every month and look at every control panel with a IR Camera to look for hot parts. It was found then.

You buy a receptacle for your dust collector and a corded plug like a dryer cord if it is 220 and a gray plastic electrical box. Get a power relay and a transformer to activate it and your all set... You could add a second relay to operate a air blast too.

AL:mrgreen:

[Jrdarrah]

I'm going to order one and give it a try. My vacuum for the CW is a shopvac so 110 will be fine. The big vac is across the shop and isn't powerful enough to pull from that distance. Thanks to all who replied. Jim