| Author |
need to turn switch on/off at 1 - 5 second intervals
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| Robert Harmon 2007-05-08, 1:25 pm |
| The subject pretty well defines my quest: need to turn switch on/off at 1 -
5 second intervals
Here's some background; I have a thermoblock that generates steam that is
too *wet*. I'd like to mount a valve (solenoid?) between the water mains &
the thermoblock that can be opened/closed at varying intervals. Can someone
point me toward a VERY cheap way to do this?
Robert Harmon
--
http://www.tinyurl.com/mb4uj - My coffee pages.
http://www.tinyurl.com/2tnv87 - My 'Guidelines For Newbies' page.
http://www.tinyurl.com/2cr3e2 - I have things for sale here.
Remove "Z" to reply via email.
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Robert Harmon wrote:
> The subject pretty well defines my quest: need to turn switch on/off at 1 -
> 5 second intervals
>
> Here's some background; I have a thermoblock that generates steam that is
> too *wet*. I'd like to mount a valve (solenoid?) between the water mains &
> the thermoblock that can be opened/closed at varying intervals. Can someone
> point me toward a VERY cheap way to do this?
Generally speaking, things in this power and timing range (1-5 secs,
AC Water solenoid) are cheapest when done mechanically. Think motor,
cam and microswitch.
| |
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| Robert Harmon wrote:
> The subject pretty well defines my quest: need to turn switch on/off at 1 -
> 5 second intervals
>
> Here's some background; I have a thermoblock that generates steam that is
> too *wet*. I'd like to mount a valve (solenoid?) between the water mains &
> the thermoblock that can be opened/closed at varying intervals. Can someone
> point me toward a VERY cheap way to do this?
>
>
> Robert Harmon
> --
> http://www.tinyurl.com/mb4uj - My coffee pages.
> http://www.tinyurl.com/2tnv87 - My 'Guidelines For Newbies' page.
> http://www.tinyurl.com/2cr3e2 - I have things for sale here.
>
> Remove "Z" to reply via email.
Assuming you have a mains powered solenoid:
+12 ---+----------------------------+-------+
|a | |
[D1] [Relay] [D2]
| | |a
+-----+-----------+---+ +-------+
| | | | |
| [1K] --------- |
| | | 8 4 | |
| +--------|7 | |
| | | | |
| P | 555 | |
| O<---+---|6 3|---+
|+ T | | |
[100uF] | | | |
| +----+---|2 |
| | | 5 1 |
| |+ ---------
| [100uF] | |
| | [.1uF] |
| | | |
Gnd ---+-----+-----------+---+
Use a wall wart 12V power supply like DCTX-1234 from
Allelectronics and a relay with contacts suitable for
your solenoid's current draw. Relay RLY-451 from
Allelectronics will handle 30 amps, so it would work.
The pot value is 100K.
Wire the relay contact in series with the solenoid
and the mains. If you don't have a solenoid, scrounge
one from an old clothes washer that is being thrown
away.
Ed
| |
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| ehsjr wrote:
> Robert Harmon wrote:
>
>
>
> Assuming you have a mains powered solenoid:
>
> +12 ---+----------------------------+-------+
> |a | |
> [D1] [Relay] [D2]
> | | |a
> +-----+-----------+---+ +-------+
> | | | | |
> | [1K] --------- |
> | | | 8 4 | |
> | +--------|7 | |
> | | | | |
> | P | 555 | |
> | O<---+---|6 3|---+
> |+ T | | |
> [100uF] | | | |
> | +----+---|2 |
> | | | 5 1 |
> | |+ ---------
> | [100uF] | |
> | | [.1uF] |
> | | | |
> Gnd ---+-----+-----------+---+
>
> Use a wall wart 12V power supply like DCTX-1234 from
> Allelectronics and a relay with contacts suitable for
> your solenoid's current draw. Relay RLY-451 from
> Allelectronics will handle 30 amps, so it would work.
> The pot value is 100K.
>
> Wire the relay contact in series with the solenoid
> and the mains. If you don't have a solenoid, scrounge
> one from an old clothes washer that is being thrown
> away.
>
> Ed
>
An equivalent adjustable commercial repeat cycle relay is available for
about $54 - may not be "VERY cheap"
http://macromatic.com/search/produc...uct=TR-53122-05
These are available 12/24/120V AC/DC and 240VAC for the timer, with
isolated contacts.
New solenoid valves might start around $20 - depends on flow rate.
--
bud--
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