vibration detector

[Jimlhebert]

Need a circuit diagrame for a simple vibration detector that will sense when my
table saw is on and operate a small relay.

 

[CFoley1064]

Subject: vibration detector
From: jimlhebert@aol.com (Jimlhebert)
Date: 2/22/2004 8:08 PM Central Standard Time
Message-id: <20040222210839.09343.00000186@mb-m12.aol.com

Need a circuit diagrame for a simple vibration detector that will sense when
my
table saw is on and operate a small relay.

If you've got a 120VAC table saw, why not just put a 120VAC relay coil across
the motor wires?

Good luck
Chris

 

[John Popelish]

Jimlhebert wrote:

Need a circuit diagrame for a simple vibration detector that will sense when my
table saw is on and operate a small relay.

I would make a current relay in an extension cord that pulls in when
the load plugged into the cord is drawing current. Then plug the saw
into that extension cord. I once made one of these to turn the
furnace blower on when the window air conditioning compressor turned
on.

--
John Popelish

 

[Jamie]

well i think if you have it powered up you have power that you can use
to trip a relay, hook into the switch!.
or are you talking about the spin down ?
there are a couple of ways..
one is to place a hall effect or some optical sensor on the shaft ,
or place a round magnet around the shaft and use the spinning effects
to push onto a steel switch.
the other ways is to make a circuit that monitors the regeneration
of the motor as it spins down.. motors will act like generator when you
disconnect power , while waiting for it to spin down i will generate
AC.
so if you were to make a low voltage monitor device that will also
handle the line voltage when on you have a good indication of when the
blade stops spinning.
using a simple OP-Amp protecting the inputs via high value resisters
into a zener you can drive a voltage comparator..
etc...
if interested i guess you could ask more about it.


Jimlhebert wrote:

Need a circuit diagrame for a simple vibration detector that will sense when my
table saw is on and operate a small relay.

 

[JeffM]

Need..a simple vibration detector
that will sense when my table saw is on and operate a small relay.
Jimlhebert

make a current relay in an extension cord
that pulls in when the load plugged into the cord is drawing current.
John Popelish

Popelish has it right: 1st dump the vibration idea.

This question has been asked here before, in almost identical words.
(Google is your friend; learn to use it.)
http://groups.google.com/groups?num=100&hl=en&lr=lang_en&ie=ISO-8859-1&safe=off&scoring=d&q=group%3Asci.electronics.*+table-saw+switch+relay&btnG=Google+Search

Jim Thompson came up with a specific (and excellent) solution:
http://groups.google.com/groups?hl=en&lr=lang_en&ie=UTF-8&safe=off&threadm=a9ntqvsg77vtudh6b0sc8v5s6tnr3cschm%404ax.com&rnum=3&prev=/groups%3Fq%3Dgroup:sci.electronics.*%2Btable-saw%2Bswitch%2Brelay%2Bjim-thompson%26num%3D100%26hl%3Den%26lr%3Dlang_en%26ie%3DUTF-8%26safe%3Doff%26scoring%3Dd%26filter%3D0

Popelish's extension-cord-assembly idea is the final touch.