Re: Toggling a latch
From: Terry Pinnell (terrypinDELETE_at_THESEdial.pipex.com)
Date: 12/13/04
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Date: Mon, 13 Dec 2004 07:56:28 +0000
Fred Bloggs <nospam@nospam.com> wrote:
>
>
>Terry Pinnell wrote:
>>
>> Meanwhile here's a schematic and notes on the present power supply
>>
>> http://www.terrypin.dial.pipex.com/Images/CurtainControllerSupply.gif
>>
>>
>
>Can this motor be PWM'ed? You might give that a try- you need something
>like 25% duty off the 12V. And since there is not a lot of difference
>between stall/run current, this is even more reason to go with a thermal
>fuse on the case to break the power.
I did think about PWM at one stage, but decided that it was probably a
bit OTT for a curtain controller. The motor is now running at a
reasonably 'calm' speed.
Re the stall/run delta, did you see my latest figures measurements?
They appear to show a quite large difference. My earlier 3.0/2.4A were
recalled from trying identical motor on the bench, fed from variable
power supply. I now realise that supply was probably inadequately
rated to give a reliable result. The *actual* motor is powered by a
heavier duty fixed 13V supply, via long cable pair to bedroom, and -
as you saw - measuring current proved more difficult than I'd
expected.
>Getting back to the suggested circuit in this subthread- although the
>LIMIT switches do not require debouncing in manual mode due to the
>latching action of the 4013, they do require debouncing in EXT mode
>because the bounce transmits directly through the SODR output
>enabling/disabling the OPEN/CLOSE outputs.
OK, good point, thanks.
>This is fixed with a 555
>one-shot which catches any bounce having effect on your final relay
>drivers, and it debounces the EXT MODE switch as well. Once again ,
>there is no memory and operation is immune to power failures which I
>assume may be of some importance to unattended operation.
I reckon my next step will be to redesign the connectors, so that I
can swap trial circuits more readily. At present, all wires go to a
set of 14 connector blocks on outside of enclosure, and then by
permanent wires to circuits. I need to isolate the relay/motor section
and make the rest easily 'pluggable'.
I'll then try your alternative circuit below, and at least the two
others from you and John Fields that are pending experiment.
I assume you saw my simulations described in
news:di3mr0lahl2g7aug1fp38ch881vucntfo2@4ax.com
and shown at
http://www.terrypin.dial.pipex.com/Images/Sim1.gif
http://www.terrypin.dial.pipex.com/Images/Sim2.gif
http://www.terrypin.dial.pipex.com/Images/Sim3.gif
http://www.terrypin.dial.pipex.com/Images/Sim4.gif
http://www.terrypin.dial.pipex.com/Images/CircuitSims1-4.gif
I have yet to simulate the toggle version.
-- Terry Pinnell Hobbyist, West Sussex, UK > View in a fixed-width font such as Courier. > > . > . __ > . +------------+-------\ \ > . U4:A | U4:B | | o->CLOSE > . +--4013-+ | +--4013--+ | +---/__/ > . TOGGLE | | +-|D /Q|-+ | U3:A > . -+- | | | | | __ > . +---o o----+-----+-|CK Q|-+--|CK Q|---------\ \ > . | | | | | | | FF | | | o->OPEN > . | [1K] | | ONE | | | | +---/__/ > . | | | | SHOT | | | SET RST| | U3:B > . | GND | +-------+ | +--------+ | > . | | | | | | > . | | | | | | > . | | | | | | > . | | | | | | > . | | | | | | > . | +--------------------------+ | > . | | TGL1 TGL2 C O| | > . | | | | > . | EXT>-|EXT | | > . | | EXTERNAL OVERDRIVE | | > . | | | | > . | | OL CL SODR | | > . | +--------------------------+ | > . | | | | | > . | | | | | > . | | | +-------------------+ > . | | | > . | C.LIMIT | | > . +----o/ o------------+ > . | | | > . | | | > . | O.LIMIT | | > . 12V-+----o/ o------+ | > . | | > . [10K] [10K] > . | | > . GND GND > . > . > . +--------------------- EXTERNAL OVERDRIVE --------------------+ > . | __ | > . | OL --------------------------------------------\ \ | > . | | >- C | > . | +--------------/__/ | > . | | U2:A | > . | | __ | > . | CL -----------------------------|--------------\ \ | > . | | | >- O | > . | | +----------/__/ | > . | __ | | U2:B | > . |TGL2---------------\ \ | | | > . | | >---------|---|--------+ | > . |TGL1---------------/__/ | | | | > . | U2:D | | | | > . | __ | | | | > . |EXT ---+---|>|---+-------\ \ | | | | > . | | | | o---|---+ | | > . | OL ---|---------|-------/__/ | | | | > . | | | U1:A | | | __ | > . | | | | | __ +-\ \ | > . | | | __ | +--\ \ | o--SODR | > . | CL ---|---------|-------\ \ | | >-+-/__/ | > . | +-\ \ | | o---+------/__/ | U3:C | > . | | | o---|-|>|-+-/__/ U2:C | | > . | +-/__/ | | | | > . | | | U1:C +--|>|--+ | > . | U1:B | | | | > . | | | | | > . | [10K] [10K] | | > . | | | | | > . | +-----+-----+ | | > . | __ | | | > . | __ +-\ \ | | | > . | +-\ \ | | o-+ | | > . | | | o---+-/__/ | | > . | 12V-[10K]-+-/__/ U1:D | | > . | | U3:D | | > . | | | | > . | | | | > . | | | | > . | | +-555---+ 1N | | > . | | | TRG|--+--||--+---+ | > . | | | | | | | > . | +-o/ o---|OUT |[10K] [100K] | > . | EXT MODE | | | | | > . | SW | | +----------+ | > . | | | | | > . | CLOSE=MODE ON | DIS|--+ | | > . | | | | | | > . | OPEN =MODE OFF | THR|--+--[470K]--+-12V | > . | | | | | | > . | | RST | ===1U | | > . | +-------+ | | | > . | | GND | | > . | +-----------------+ | > . | | > . | | > . | CLOSE | > . | ----- | > . | | | | > . | EXT-> | | | > . | | | | > . | OPEN | | OPEN | > . | ----- ------ | > . | | > . | (from LDR ckt ) | > . | | > . +-------------------------------------------------------------+ > . >
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