can anyone help what voltage poly cap do i need

[gasket]

hiya guys im trying to build an led tachometer but I don't know what voltage the polyprop capacitors are I have attached the wiring diagram and here is the parts list any help would be appreciated
LEDs:21 LEDs of any color you want. I used bright white ones. You can use some green, some yellow & some red for the red zone. You MUST use bright ones if you are planning to put paper covers over the LEDs or they are going to be simply invisible
The first LED is continously lit as long as the +12V source is connected. The remaining 20 will be lit one by one as you increase the engine speed

Diodes:
1 x 1N4007
1 x 1N4148
1 x Zener diode 12 Volts

Resistors:
1 x 220 Kohm Trimpot variable resistor (for calibration)
2 x 1 Kohm
3 x 10 Kohm
1 x 22 Kohm
1 x 2.2 Kohm
1 x 470 ohm

Electrolytic Capacitors:
1 x 470 µFarad 25 Volts (µ = micro)
1 x 2.2 µF 16 Volts

Polypropylene Capacitors:
3 x 100 nF (nano)
1 x 47 nF
1 x 1 µF

 

[Inquisitive]

Photos? Please attach photos.

 

[gasket]

should be a wiring diagram there now

 

[DerStrom8]

I imagine you couldn't go too far wrong with 25v, seeing as your powering the system off of 12v. It'll allow for any voltage spikes that the circuit might see. In general you could probably use any voltage between 16v and 50v (possibly higher?) but I imagine 25 volts would be your best bet.

 

[eTech]

Hi

eT

 

[ScottS]

I imagine you couldn't go too far wrong with 25v, seeing as your powering the system off of 12v. It'll allow for any voltage spikes that the circuit might see. In general you could probably use any voltage between 16v and 50v (possibly higher?) but I imagine 25 volts would be your best bet.

A common design adage when it comes to caps is the almost universal "rule of three" it falls in in first aid ( three minutes with out breathing and so on) three miles before having to stop for the wife to pee, three hours and the move is too long... one of those odd truisms of life. so in the design world we look for a capacitor rated the closest to three times the DC input voltage, as both a safety and longevity factor. In relatively recent times, 10 to 15 years, many cut rate computer motherboard manufacturers had been going below this unwritten rule, and using "as rated" or as close to possible, caps to cut costs, only to have them fail in short order. Usually within a half year after going out of warranty, even though the electrolytic would bulge before completely failing. Never go less than double your DC source voltage, try to go triple, or as close as possible and you will do fine. It just one of Life's odd truisms like needing anti diarrhea medicine the most when there is no toilet available

 

[tvtech]

A common design adage when it comes to caps is the almost universal "rule of three" it falls in in first aid ( three minutes with out breathing and so on) three miles before having to stop for the wife to pee, three hours and the move is too long... one of those odd truisms of life. so in the design world we look for a capacitor rated the closest to three times the DC input voltage, as both a safety and longevity factor. In relatively recent times, 10 to 15 years, many cut rate computer motherboard manufacturers had been going below this unwritten rule, and using "as rated" or as close to possible, caps to cut costs, only to have them fail in short order. Usually within a half year after going out of warranty, even though the electrolytic would bulge before completely failing. Never go less than double your DC source voltage, try to go triple, or as close as possible and you will do fine. It just one of Life's odd truisms like needing anti diarrhea medicine the most when there is no toilet available

Hi Scott

Now that is an interesting post. I am all ears (I have big ones ).

Regards,
tvtech