switch help

D

dave_bert

New Member

• Oct 10, 2010

• #1

hello
I am trying to automate a process in a machine.
the machine has an input for an external trigger.

I am in need of a programmable on off switch?

depending on the way the machine is set defines how long the system has to be ON.

from a first timer

thank you

Dave

 

MikeMl

Well-Known Member

Most Helpful Member

• Oct 10, 2010

• #2

Dave,

I have difficulty understanding what you need?

Do you need a circuit that periodically generates a pulse to trigger your machine with no user intervention?
How long should the trigger last?
How long before the next trigger happens?
What voltage level does it take to trigger the machine?

 

D

dave_bert

New Member

• Oct 10, 2010

• #3

the machine just needs a circuit completed to cause it to function

the length of time the circuit is dependent on how the machine is set.(this is y i am looking for something programmable)

sorry for sounding so dumb but electronics is not my field

thank you

Dave

 

MikeMl

Well-Known Member

Most Helpful Member

• Oct 10, 2010

• #4

Ok, so the output from the "trigger" is a contact-closure, like a relay?

What voltage does it take to operate the machine?
AC or DC?
How much current does the machine require?

How do you want to program the trigger? Turn a knob? Turn a screwdriver? Using a computer?

 

Last edited: Oct 10, 2010

D

dave_bert

New Member

• Oct 10, 2010

• #5

the current trigger is a momentary switch

i am wanting to use a computer to program the switch

i am hoping this is helping

thanks
Dave

 

MikeMl

Well-Known Member

Most Helpful Member

• Oct 10, 2010

• #6

Hang in there, Dave.

A computer like a Windows PC?

How often do you push the switch?

How long before you push the switch a second time?

 

D

dave_bert

New Member

• Oct 10, 2010

• #7

i would like to use a PC or laptop

i push and hold the switch for various lengths of time depending on the setting of the machine(the switch must be held for the cycle to complete)

i would like to also be able to program the time between each cycle(?) from seconds to minutes

from as few as once ( as a test) to however many times

thank you for the help

Dave

 

MikeMl

Well-Known Member

Most Helpful Member

• Oct 10, 2010

• #8

Suppose you could turn a relay on/off via USB, a serial port, or a parallel port on your computer, are up to creating the program that would control it?

There is off-the-shelf hardware available to control a relay from a computer, but it requires creating a program in Visual Basic, or other programming language.

Read this thread in the other forum. It seems like this deals with your topic.

 

Last edited: Oct 10, 2010

D

dave_bert

New Member

• Oct 10, 2010

• #9

is their a thread on the actual hardware

thank you

Dave

 

MikeMl

Well-Known Member

Most Helpful Member

• Oct 10, 2010

• #10

The voltage levels that come out of a serial port are well documented. A circuit that would pull-in a small relay based on the state of the DTR or RTS line in a serial port is something I can post here.

Or Google is your friend: use "control a relay with serial port" as the search keywords.

 

Last edited: Oct 10, 2010