In this post I have explained a simple yet useful 10 step selector switch circuit which can be operated using a singe push-to-ON switch. In the following design the circuit is used as a 3 step, single push motor speed controller unit. The circuit was requested by Mr.Edalcor.
Technical Specifications
hi sir good day to to you, can you please design me a circuit with only one switch (a push button) to control the speed of my dc motor 1st push low, 2nd push medium and 3rd push high the output will go to my 12 volts relay there are 3 relay for low med and high, and the output of my relay will be going to my dc motor with rheostat to control the speed i want to use it for my car air-con. thank you and more power to your blog.
Circuit Diagram
How it Works
The IC 4017 is a johnson decade counter IC with 10 decoded output, designed to produce sequential logic high outputs in response to high/low alternate logic switching at its pin#14.
Here pin#14 of the IC is switched or toggled using a push button switch, which generates the shifting high logic pulses across the output pinouts of the IC starting from pin#3 to pin#11.
However in the shown design since only 3 outputs are used for implementing 3 relay based switches, the IC is resets back to the first pinout as soon as the logic sequence reaches pin#7 of the IC.
If you want to implement a 10 relay operation in that case you can configure the transistor relay driver stages across all the 10 output pins of the IC.
Application Circuit:
The above concept can be applied as a 3 step LED brightness controller through a single push button, as shown below:
The above design can be further improved, as shown in the following diagram:
Questions & Answers
nice one sir thank you very much i will appreciate your effort of doing this i will try it. My last comment sir, if i push it on the fourth time it will be off?
Yes, the fourth push will reset the circuit to zero or pin#3 which is an unused output, rendering all the relays to off position.
hi sir, again I'm here to bother you. Can i have another request? Can you please design a PWM circuit that fit my A/C blower motor to replace my rotary switch? It is cool if a potentiometer vary the speed of my blower. More power to your blog and thank you.
hi edalcor, why don't you try a dimmer switch for it, you can get pretty cheaply from your local electrical shop?
I have explained it here:
https://www.homemade-circuits.com/2012/04/how-to-make-simplest-triac-flasher.html
i'm sorry sir i forgot to indicate A/C blower motor 12 volts for my car.
do you mean you want to operate a 220v ac motor with a 12V DC input??
no sir the my 12volt evaporator motor in my car air conditioning unit i want to convert the control unit i.e.(fan speed) to PWM instead of the conventional rotary type circuit. thanks for your time.
OK, you can use the following circuit for the application:
https://www.homemade-circuits.com/2012/05/make-this-pwm-based-dc-motor-speed.html
Good One Sir..!!!
Can this concept be used in Home used Mixer-Grinder???
yes surely, but the whole thing with the relays would become too expensive.
ZABARDAST !!!
😀
sir, I want a circuit for control three relay using touch switch(first touch ON and Second is OFF)
You can use the above circuit for the application, just replace the push button terminals with metal pads held close by, …..touching the pads together will enable touch triggering of the relays.
Hai sir: How ten relay circuit maiking tell me plz,,,
Use all the 10 outputs of the IC4017 and connect relays to them in the manner shown above.
For knowing the output pinout sequence order you can refer to the following article:
https://www.homemade-circuits.com/2011/12/how-to-understand-ic-4017-pin-outs.html
great information..
you can use an SPDT switch rated at 20 amps and wire the units through them.
one of the supply input can be wired as common to both the systems, this will engage two wires of the two loads with this common line, next pick the the other supply input and connect it with the center lead of the SPDT switch, after this the remaining two ends of the switch may be terminated with the free supply inputs of the loads individually.
Sir,
I'm here again to disturb you. Please……
If any of the out put terminal left open between two close out put terminal then wheather it will reset at open terminal switching or not ?
With regards,
k.kausik
Kikira, are you referring to the 4017 IC output pins? if yes then the answer is no…it won't reset if any of the output pins is left open….it will reset only if it's connected with pin15 of the IC
Sir,
Have a look on the above circuit and please inform 3v :1/3w zener number and other diodes are 4148 means must be zener but in figure they are simple .
As I have collected all the parts and ready to solder, expecting your final touch as soon as possible.
Thanking you,
K. Kausik
Kaushik, the diodes connected in parallel to the relay coils are all 1N4007.
The one which is marked 3V, 1/4w is the zener diode.
Sir,
What's the pin no. of ic-4017 just left behind of the pin 15.in the fig.
Thanking you,
K. Kausik
it's pin#16, the supply pin of the IC
Sir,
In this moment I'm under the debris. The above ckt that I made, is working well when I connect a led. But a 12v even if a 6v relay is'nt working.please help.
Egarly waiting for your kind guidance.
With regards,
k.kausik
your relay might not be working due to one of the following reasons:
transistor emitter not connected to the circuit negative line.
transistor pins wrongly connected.
transistor is burnt or faulty.
relay coil resistance is too low for the transistor to make it work.
relay diode is faulty or with wrong polarity…which might eventually burn the transistor
connect a LED with a series 1k resistor parallel to the relay coil, to check the transistor response and whether the transistor is conducting as expected or not.
Sir,
Many many thanks for your quick and valuable advice. But sorry to say none of the relay is responding though leds are.
With regards,
K.kausik
Kaushik, please investigate and check the above mentioned points for finding the exact fault in your circuit.
Sir,
In this late night I have found a solution. I connected the base of a 557 with the collector
of 547 instead of a relay. Then a relay with the557 & a parallel diode 4007. For your kind information now the relay is working.
How is it possible ? Would you kindly explain it…….
Thanking you,
k.kausik
kaushik, it's because your relay has a low coil resistance and requires more current to operate…adding another transistor simply boosts the current and allows the relay to operate.
use 1K at the base of the BC547 and try the previous configuration, without the BC557
or you must use the type of relay which is shown below
1.bp.blogspot.com/-xpR6CBVr5RY/VB7jiU5puOI/AAAAAAAAIRA/gKnCI1xGHFA/s1600/relay%2Bpinout.png
Dear sir,
Good morning and many many thanks for your kind reply. Actually I belong small city of u.p. Though this is the SADAR but there is only one reliable electronic store. The relay that you maintioned is not available here and adding 1k resistor was unsuccessful.
I think it's O.K to add an extra 557 if it is not harmful for the ckt.
With regards and thanks a lot,
K. Kausik
OK kaushik, no problem you may go ahead with it…
alternatively you can also try a BC547 in the Darlington mode, that is by using two BC547 on each channel…this will give you the same results.
Good day sir,
Would you kind help me with the adjust ment to connect the ckt to a 12v/1.5 amp tr.
Thanking U….
K. Kausik
Kaushik, no adjustments would be required in the above circuit.
you just have to make a bridge rectifier and add a filter capacitor to it for converting the trafo secondary AC to DC…this rectified DC can be then connected with the above circuit.
Sir,
Sorry to disturb you. I have already a bridge rec. added with the tr. but 3 ic's has damaged… I think it's due to over current….any how thanks for your kind feedback. I have (already posted on realated ckt.) an another prob. realated with led.. if you kindly take care of it I wil be highly grateful to you….
With regards,
K. Kausik
it may be because of the stepped up voltage after rectification….use a 7812 IC after the trafo DC, this will safeguard the circuit and the IC.
Sir can we use above circuit for time interval switching (interval 3 sec) continuous switching? what is working lifespan of relay? Any other option for relay?
Ashok, yes you can use the circuit for 3 sec continuous switching….relays can have a permanent life and be stress resistant as long as the current through its contacts are much below the rated limit
other option will depend on the load and supply specs
Thanks for your circuit and working it fine, but I want to know will I keep all session in swich on state undil reset the circuit, that means in first push switch on session one and second push switch on session two keep the first session in on state? And what I have to do for this needs, I need 4 steps like these fucrionality
to keep the outputs switched ON you will need to replace the single transistors with a two transistor latch circuit as shown in the following article:
https://www.homemade-circuits.com/2011/12/simple-and-useful-transistor-latch.html
you may need 4 such circuits connected across the 4 outputs of the IC 4017
for resetting you may have to switch OFF the entire circuit and then switch it ON.
thank you for your suggestion and i added two transistors bc547 ,bc557 driven by output0 pin#3 bc557 output to T1 of entire circuit suggested by you. in each session spend 4 transistors. and now it working fine. it made for a led drive dimmer for mirror in my home. thank you again ,
I am glad it worked for you…..but 4 transistors on each channel is not required, the latch circuit uses two just transistors…so it should be two transistors and a relay on each channel??
Really thanking you again for quick response and spending time for my doubts and needs. I did that with total 4 transistors . and tried with 3 but not working. how can send my diagram i modified . ?
OK thanks, just forgot to mention that the outputs of the 4017 should be connected through a diode with the latch circuits, otherwise the latch cannot hold due to the negative trigger by the 4017 while it changes its sequence…
you can use 1N4148 diodes….anode to 4017 IC pins and cathode to the latch trigger inputs.
Ok thank you sir, and I have problem with touch when i extended my lead up to 15cm
Asainar, the above circuit is designed to work with a push switch, a touch sensor might require a different configuration…
Sir I used your touch sensor circuit using 4017 used 2 nos of bc557 in input signal of 4017,
what kind of problem are you facing?
Good useful ckt. you have posted. I would like to know whether the PUSH-TO-ON SWITCH – is it a momentary switch – or push to on and then push to off switch?