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555 timer reverse polarity circuit

G'day, I'm nearly there with the build but have a query, after ordering the components i noticed my supplier supplied a 470uf 25v electrolytic capacitor as opposed to your suggestion of a 400uf 25v electrolytic capacitor. If i use this capacitor will i have to change the values of the resistors to suit ?
regards
Chris
 

CDRIVE

Hauling 10' pipe on a Trek Shift3
Electrolytics have a tolerance of +- 20%, so I wouldn't loose sleep over it. Yours is not a critical timing sequence anyway. I don't think it will matter much if the timing sequence is 1min or 2min as long as each Pos & Neg cycle is about the same. Keep in mind that the first couple of timing intervals will be longer and possibly unbalanced until the cap forms itself.

Chris
 
Welshdragon, can I ask you to somehow share your "cart" with me please? I'm new to this and want to start this project with all the parts, then I can build from there. Thank you so much for the help cdrive and others.

edit: this is what i put together, what do you think?

https://www.electronicspoint.com/atta...hi1minlo-3.jpg

************* Notes **************
All Resistors are 1/4W
All Disc Caps are rated >= 25VDC
C2: Electrolytic >=25VDC
K1: Can be any SPDT relay with a coil resistance >= 400 Ohms
and contacts rating >= 500mA

C3 100n
R3 10k
D1 1N914
R5 2M
C2 400u
C1 10n
R 4220k
555 timer U1 (anything accommodate 30 volts?
D2 1N4002
K1 12V SPDT
R1 120
R2 200

1/4 LEDS, RED AND GREEN ?

My left over questions are what do i put this stuff in after its done? and where is the best one stop shop for all of these parts?
 
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CDRIVE

Hauling 10' pipe on a Trek Shift3
Welshdragon, can I ask you to somehow share your "cart" with me please? I'm new to this and want to start this project with all the parts, then I can build from there. Thank you so much for the help cdrive and others.

Actually, I've never really known what the project does. I assumed it was some type of electrolysis but I'm short on the details. ;)

Chris
 
Shoot I cant pm you because my post count is so low cdrive. Were basically making the "perfect" silver water or also known as colloidal water. It fixes all sorts of heath issues.
 

CDRIVE

Hauling 10' pipe on a Trek Shift3
Shoot I cant pm you because my post count is so low cdrive. Were basically making the "perfect" silver water or also known as colloidal water. It fixes all sorts of heath issues.

That's OK, I don't answer questions via PM anyway. It's not conducive to the purpose of the forum. Thanks for filling me in on silver water though.

Chris
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Shoot I cant pm you because my post count is so low cdrive. Were basically making the "perfect" silver water or also known as colloidal water. It fixes all sorts of heath issues.

I have a bridge I need to sell
 
Hopefully this will be the last version of this. The LEDs were moved into the constant current legs of the supply as ElectroBrain suggested.

************* Notes **************
All Resistors are 1/4W
All Disc Caps are rated >= 25VDC
C2: Electrolytic >=25VDC
K1: Can be any SPDT relay with a coil resistance >= 400 Ohms
and contacts rating >= 500mA
http://www.mpja.com/12VDC-SPDT-Essex-Relay/productinfo/18454+RL/

Hello CDRIVE,

I am late to the party, hoping you are still out there. Just wanted to say thank you very much! Having zero experience, your design is the perfect starting place for me to get my feet wet.

A clarification question... Regarding "COM" to ground. I have been trying to look this up as I did with everything else. Can you (or anyone) clarify what those 2 are and the "OUT" above the bottom COM?

Thanks again and have a great day.
 

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Bypass Capacitors?

Are those 3 Bypass Capacitors? If so, would .1uF 25V be sufficient?

For the sake of illustration, I will refer to the 3 from top to bottom as 1 COM, 2 OUT and 3 COM

1 COM - Neg to Ground - Nothing to Positive (side).
2 OUT - Positive into circuit - Nothing to Negative (side).
3 COM - Neg to Ground - Nothing to Positive (side).

Thank you to anyone that can validate or say "hit the books buddy".

Have a great day.
 

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I have not been following this thread which seems to have gone on and on.

COM is short for common, in other words all these points should be connected together. It would be clearer if a line were drawn across the bottom of the diagram and all the connections went to this. I do not like lumps of ground floating in the sky. :)

There is a relay which connects either +30V or -30V to the output terminal (relative to COM).
 
COM/OUT

Hi Duke37,

Thank you for taking the time to reply. I really appreciate it.

I think I've had to much fluoride... so please forgive my ignorance I as I try to grasp these floaters...

OUT will connect to Pin 3 on the 555. This next part I am hazy on... COMs connect to Pin1? The reason I ask is because Pin1 is already Grounded. So obviously I am missing something. :confused: I guess I am unclear as to what is being grounded in these 2 cases.

Thank you for your patience and time. :)

Michael
 
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davenn

Moderator
OUT will connect to Pin 3 on the 555.

No, Out is the output from the relay contacts it goes to what ever other circuit is being controlled
( if it went to pin 3 of the 555 it would have shown that)

This next part I am hazy on... COMs connect to Pin1? The reason I ask is because Pin1 is already Grounded. So obviously I am missing something. :confused: I guess I am unclear as to what is being grounded in these 2 cases.
Thank you for your patience and time. :)
Michael

Yes everything that has COM and the ground symbol are connected together .... NOTE the input from the negative lead of the power supply also goes there


Dave
 
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The common is wallpak -,C1,C2,C3,P1 and const current COM.
These are all at the same potential.

P3 is the output of the 555 which drives the relay coil.
 
COM/OUT

The common is wallpak -,C1,C2,C3,P1 and const current COM.
These are all at the same potential..

Hi Duke,

I guess that is what my problem is... with these floaters. I understand that they are grounded. But without lines connecting the dots, I don't get the other side of the equation. What is being grounded (2 COM) (and where does OUT go)?

I have learned so much about the components from the connected diagram. It took me six hours to order the parts as I researched each... But these floaters are in the same boat as those dust particles that float in your eye and drive you crazy trying to watch them.

Losing my mind on this... but probably just need a good nights sleep to look it over again and study more diagrams ;) If anything, I think it wise to start on breadboard and test/learn, before I fry parts with a solder gun. :eek:

Thank you for your guidance. I know the answer is very obvious to you all...
 

davenn

Moderator
......and where does OUT go?
whatever is receiving the switched voltage

follow the out back see where it comes from .... the common of the relay contacts.
the other contacts of the relay are +30V and - 30V
when the relay is operated on and off by the timer circuit, the out connection has either +30 or -30 Volts

Dave
 
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whatever is receiving the switched voltage

follow the out back see where it comes from .... the common of the relay contacts.
the other contacts of the relay are +30V and - 30V
when the relay is operated on and off by the timer circuit, the out connection has either +30 or -30 Volts

Dave

Hello Dave,

Thank you very much for that explanation. This really clears it up for me.

Out of curiosity... Are all diagrams like this? In that a designer uses "shorthand" when drawing diagrams up? If so, I think I will be buying some books. :D

Thanks again and have a great day.

Michael
 
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