Looking for a Low Cost On Delay Timer

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Names can be confusing, so here's what I'm doing....

http://img43.imageshack.us/img43/7434/wvm.gif

When 12VDC is applied to the input, I need a 12VDC output for 5 seconds.  
 Then output will go back off and stay off until the input goes to zero.  
 Then cycle starts again.

Current for both legs is in the 10-50ma range.

A simple on-delay timer would work but I'm having trouble finding one  
with NC contacts.  Tons of stuff $100+, but for this application, it has  
to be under $20.

Thanks,


Bob


Re: Looking for a Low Cost On Delay Timer
Check the specs of an Altronix 6060



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Re: Looking for a Low Cost On Delay Timer
Bob La Londe Wrote:  

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Or the 6062.  I think they are about $30.

http://www.altronix.com/products/product.php?name=6062



--  

They who can give up essential liberty to obtain a little temporary safety,
 deserve neither liberty nor safety. - Ben Franklin

Re: Looking for a Low Cost On Delay Timer
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safety,

Thanks guys.  Grainger has it for $30.   Before I head up there... this  
is not something that has to be done right away...   would putting  
together a circuit with this work?

NTE955M Timer, (555 Type), 200 mA Iout, CMOS 8 DIP 1.20
http://www.alliedelec.com/search/productdetail.aspx?sku=70215850


Re: Looking for a Low Cost On Delay Timer
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A transistor /amplifier Ic, plus a capacitor, and a few resistors should
do it. What time scales you you need? How fast does it need to switch on
and switch off? What voltage tolerance do you need? -- ie if it is 11V
out is that OK? What supply voltage do you have? Can the input drop to
zero before 5 sec and what behaviour do you expect in that case?
How accurate must the 5 sec be? etc

Re: Looking for a Low Cost On Delay Timer
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safety,
this is not something that has to be done right away...   would putting  
together a circuit with this work?
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should
on

Hey unruh!

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should

Initially input voltage is zero.  When input goes to 12VDC, output  
should energize immediately to 12VDC, stay eneregized for 4-6 seconds,  
then drop to zero again.  When input goes to zero, output stays off  
until starts over.

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Within 1/2 second is fine.

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Yes, 9-13 out is fine.  Supply is typically 11-12VDC.

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expect in that case?
Yes it can.  Output should go on when input first goes on, then output  
should go off any time input is disconnected.

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4-6 seconds is fine.  Not critical.



Re: Looking for a Low Cost On Delay Timer
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Immediately does not mean anything. on a time of 5 sec?1 sec 1
millisecond? 10^-100 sec? If you are looking at relays, they are of
order 1/10 sec. Is that good enough?


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OK.


So a simple rc circuit opamp  should be fine.

The input goes through a resistor divider to the + input of an opamp,
the input also goes through a resistor (with a parallel reverse diode)) to a
capacitor to ground, and the junction of reistor and capacitor goes
to the - input of the opamp.  
When input goes up, the output of the opamp will peg out positively,
until the capacitor charges up sufficiently at which point the ouput
will go to zero the resistor/capacitor is chosen so that this is 5 sec. If
the output goes to 0, the capacitor is discharged by the divider  and the
output stays at 0. If the resistor bridge low enough (say 1K ohm) and
the risistor/capacitor high enough (eg R=100K C= 2uF) -- I have not
checked these values -- they are at best orders of magnitude-- you would
not need the diode.

You could run a very high resistor from the cap to the positive
rail as well, to make sure that when the input is low, the capacitor
remains slightly charged, and the opamp is driven to low output.  

Total cost ? < $1
Output current-- only limited by the opamp output current which could be
thousands of amps with suitable(very expensive) ouput transistors.
(for cheap opamps hundreds of mA.)


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Re: Looking for a Low Cost On Delay Timer
You could do it with some 555s and some resistors, relays, etc, but why?  

  

Re: Looking for a Low Cost On Delay Timer
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relays? why? His current demands are 10s of mA. That the opamp can
handle by itself.  
Cost? $1 vs $30? While the former may not matter to you or to most as a
oneoff, if he has to build 100000 of them, it can be significant.
We have no idea what he wants this for.
  
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Re: Looking for a Low Cost On Delay Timer
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I wouldn't build 10K of them.  I'ld post an RFQ and spend my time selling  
the second 10K.


  


Re: Looking for a Low Cost On Delay Timer
["Followup-To:" header set to alt.security.]
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He has not told us what he is doing. You are perfectly correct if a) it
is one off, b) it is a job, and c) he can actually get them in a
reasonable time. Remember it can take 10s of sheets of paperwork, 5
signatures and 2 week wait time sometimes to get one object. Whipping up
a little circuit with spare parts can be done in 10 min.

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Re: Looking for a Low Cost On Delay Timer
Names can be confusing, so here's what I'm doing....

http://img43.imageshack.us/img43/7434/wvm.gif

When 12VDC is applied to the input, I need a 12VDC output for 5 seconds.  
 Then output will go back off and stay off until the input goes to zero.  
 Then cycle starts again.

Current for both legs is in the 10-50ma range.

A simple on-delay timer would work but I'm having trouble finding one  
with NC contacts.  Tons of stuff $100+, but for this application, it has  
to be under $20.

===

Thanks for all the tips and good info.  I had wanted to put something  
together from components but my brain is too far behind these days.  I'm  
going to give this a shot and hopefully I'm not picking the wrong one.  
It's $5 at Frys...

Velleman MK111
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf








Re: Looking for a Low Cost On Delay Timer
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Except that looks like an oscillator rather than a "oneshot"  
You said that you wanted something that if the input was larger than 5
sec, the output would go high for 5 sec, and then drop to 0. If the
input droped before 5 sec was up, you wanted the output to drop as well.
Then you wanted it to wait until the input went high again before doing
that again.
This device has a relay (why would you need a relay for 50ma? Most ICs
can handle an ouput current of 50mA at 12V without the need of a relay.

This kit is an oscillator, where you can adjust the time it is on and the
time it is off with the pots. It has no input.  

It uses a 555 timer chip. The primary design of the 555 is to initiate a
pulse when the input goes high, and stays high for the requsite time
even if the input drops again. If the input stays high beyond the time
Ie, I think you want to think your way through what you need carefully.

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Re: Looking for a Low Cost On Delay Timer
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seconds.  Then output will go back off and stay off until the input goes  
to zero.  Then cycle starts again.
Quoted text here. Click to load it
one with NC contacts.  Tons of stuff $100+, but for this application, it  
has to be under $20.
Quoted text here. Click to load it
something together from components but my brain is too far behind these  
days.  I'm going to give this a shot and hopefully I'm not picking the  
wrong one.  It's $5 at Frys...
Quoted text here. Click to load it
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
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well.
doing
relay.
the
a
carefully.

Thanks, yes you're right.   What value resistor could I substitute for  
RV1 to give a pause time between pulse to 10 minutes?







Re: Looking for a Low Cost On Delay Timer
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seconds.  Then output will go back off and stay off until the input goes  
to zero.  Then cycle starts again.
Quoted text here. Click to load it
one with NC contacts.  Tons of stuff $100+, but for this application, it  
has to be under $20.
Quoted text here. Click to load it
something together from components but my brain is too far behind these  
days.  I'm going to give this a shot and hopefully I'm not picking the  
wrong one.  It's $5 at Frys...
Quoted text here. Click to load it
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
Quoted text here. Click to load it
well.
doing
relay.
the
a
carefully.

- Thanks, yes you're right.   What value resistor could I substitute for  
RV1 to give a pause time between pulse to 10 minutes?

PS -- This will actually give me another option I can use instead of  
just the one-shot.






Re: Looking for a Low Cost On Delay Timer
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RC=t roughly. (depends on exactlywhee in the charge/discharge cycle the
thing triggers). But R probably should not be much over 1Mohm, as
otherwise the input resistance of the ic becomes important.  
Then C should be about 600uF (probably not electrolytic as the internal
resistance can become important but finding anything else at that size
is pretty impossible)

)



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Re: Looking for a Low Cost On Delay Timer
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seconds.  Then output will go back off and stay off until the input goes  
to zero.  Then cycle starts again.
Quoted text here. Click to load it
finding one with NC contacts.  Tons of stuff $100+, but for this  
application, it has to be under $20.
Quoted text here. Click to load it
something together from components but my brain is too far behind these  
days.  I'm going to give this a shot and hopefully I'm not picking the  
wrong one.  It's $5 at Frys...
Quoted text here. Click to load it
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
Quoted text here. Click to load it
than 5
well.
doing
ICs
relay.
and the
initiate a
time
time
carefully.
for RV1 to give a pause time between pulse to 10 minutes?
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the
internal

Thanks.   I think I'll put a fixed 2M ohm in series and see if I can get  
a 3-5 minute range.


Re: Looking for a Low Cost On Delay Timer
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seconds.  Then output will go back off and stay off until the input goes  
to zero.  Then cycle starts again.
Quoted text here. Click to load it
finding one with NC contacts.  Tons of stuff $100+, but for this  
application, it has to be under $20.
Quoted text here. Click to load it
something together from components but my brain is too far behind these  
days.  I'm going to give this a shot and hopefully I'm not picking the  
wrong one.  It's $5 at Frys...
Quoted text here. Click to load it
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
Quoted text here. Click to load it
than 5
well.
doing
ICs
relay.
and the
initiate a
time
time
carefully.
for RV1 to give a pause time between pulse to 10 minutes?
Quoted text here. Click to load it
the
internal

- Thanks.   I think I'll put a fixed 2M ohm in series and see if I can  
get a 3-5 minute range.

http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf

If I disconnect pin 7, would that make it a one-shot pulse?



Re: Looking for a Low Cost On Delay Timer
On Thursday, August 29, 2013 1:17:30 PM UTC-4, Guv Bob wrote:
guvbob2003@yahooooooooooooooo.com> wrote in message news:1_udnQ7rBpNjRo7PnZ
2dnUVZ_sidnZ2d@earthlink.com... > >> > Names can be confusing, so here's wh
at I'm doing.... > >> >> > >> >> http://img43.imageshack.us/img43/7434/wvm .
gif > >> >> > >> >> When 12VDC is applied to the input, I need a 12VDC outp
ut for 5 seconds. Then output will go back off and stay off until the input
 goes to zero. Then cycle starts again. > >> >> > >> >> Current for both le
gs is in the 10-50ma range. > >> >> > >> >> A simple on-delay timer would w
ork but I'm having trouble finding one with NC contacts. Tons of stuff $100
+, but for this application, it has to be under $20. > >> >> > >> >>==
= > >> > > >> > Thanks for all the tips and good info. I had wanted to pu
t something together from components but my brain is too far behind these d
ays. I'm going to give this a shot and hopefully I'm not picking the wrong  
one. It's $5 at Frys... > >> > > >> > Velleman MK111 > >> > http://www.vell
emanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf > >> > >> Except  
that looks like an oscillator rather than a "oneshot" > >> You said that yo
u wanted something that if the input was larger than 5 > >> sec, the output
 would go high for 5 sec, and then drop to 0. If the > >> input droped befo
re 5 sec was up, you wanted the output to drop as well. > >> Then you wante
d it to wait until the input went high again before doing > >> that again.  
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 > >> can handle an ouput current of 50mA at 12V without the need of a rela
y. > >> > >> This kit is an oscillator, where you can adjust the time it is
 on and the > >> time it is off with the pots. It has no input. > >> > >> I
t uses a 555 timer chip. The primary design of the 555 is to initiate a > >
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 even if the input drops again. If the input stays high beyond the time > >
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 > > > Thanks, yes you're right. What value resistor could I substitute for
 RV1 to give a pause time between pulse to 10 minutes? > > RC=t roughly.  
(depends on exactlywhee in the charge/discharge cycle the > thing triggers)
. But R probably should not be much over 1Mohm, as > otherwise the input re
sistance of the ic becomes important. > Then C should be about 600uF (proba
bly not electrolytic as the internal > resistance can become important but  
finding anything else at that size > is pretty impossible) - Thanks. I thin
k I'll put a fixed 2M ohm in series and see if I can get a 3-5 minute range
. http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
If I disconnect pin 7, would that make it a one-shot pulse?

Jeeeeeze, If you'd have bought the damn Altronix 6062 you'd have been up an
d running in 15 minutes instead of EF-en around with this $5.00 piece of cr
ap.  

I just don't understand some people I guess.



Re: Looking for a Low Cost On Delay Timer

On Thursday, August 29, 2013 1:17:30 PM UTC-4, Guv Bob wrote:
be confusing, so here's what I'm doing.... > >> >> > >> >>  
http://img43.imageshack.us/img43/7434/wvm.gifWhen 12VDC  
is applied to the input, I need a 12VDC output for 5 seconds. Then  
output will go back off and stay off until the input goes to zero. Then  
cycle starts again. > >> >> > >> >> Current for both legs is in the  
10-50ma range. > >> >> > >> >> A simple on-delay timer would work but  
I'm having trouble finding one with NC contacts. Tons of stuff $100+,  
but for this application, it has to be under $20. > >> >> > >>  
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wanted to put something together from components but my brain is too far  
behind these days. I'm going to give this a shot and hopefully I'm not  
picking the wrong one. It's $5 at Frys... > >> > > >> > Velleman MK111 >  
Quoted text here. Click to load it
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
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5 > >> sec, the output would go high for 5 sec, and then drop to 0. If  
the > >> input droped before 5 sec was up, you wanted the output to drop  
as well. > >> Then you wanted it to wait until the input went high again  
before doing > >> that again. > >> This device has a relay (why would  
you need a relay for 50ma? Most ICs > >> can handle an ouput current of  
50mA at 12V without the need of a relay. > >> > >> This kit is an  
oscillator, where you can adjust the time it is on and the > >> time it  
is off with the pots. It has no input. > >> > >> It uses a 555 timer  
chip. The primary design of the 555 is to initiate a > >> pulse when the  
input goes high, and stays high for the requsite time > >> even if the  
input drops again. If the input stays high beyond the time > >> Ie, I  
think you want to think your way through what you need carefully. > > >  
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RV1 to give a pause time between pulse to 10 minutes? > > RC=t  
roughly. (depends on exactlywhee in the charge/discharge cycle the >  
thing triggers). But R probably should not be much over 1Mohm, as >  
otherwise the input resistance of the ic becomes important. > Then C  
should be about 600uF (probably not electrolytic as the internal >  
resistance can become important but finding anything else at that size >  
is pretty impossible) - Thanks. I think I'll put a fixed 2M ohm in  
series and see if I can get a 3-5 minute range.  
http://www.vellemanusa.com/downloads/0/minikits/manuals/manual_mk111.pdf
If I disconnect pin 7, would that make it a one-shot pulse?

Jeeeeeze, If you'd have bought the damn Altronix 6062 you'd have been up  
and running in 15 minutes instead of EF-en around with this $5.00 piece  
of crap.  

I just don't understand some people I guess.

===

Time is not a big deal for me.   This is more of a learning project for  
me.


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