1N4001 for bridge rectifier?

[RogerTango]

Can I use the 1N4001 diode to build a full wave bridge rectifier for 110vac mains to dc?

Also- What is the max dc voltage an LM7805 regulator can take?

Thanks-
Andrew

 

[audioguru]

The peak voltage of 110VAC is 155V. If it rises to 120V then the peak voltage is 170V. Spikes might increase the peak to 380V.
A 1N4001 has a max allowed voltage of only 50V. Use 1N4004 diodes rated at 400V.

Look at the datasheet for a 7805. Texas Instruments recommends a max input of 25V. Of course the voltage across it times the current through it determines how hot it will get.

 

[RogerTango]

Thanks much Guru! You have really helped me to learn!!

Andrew

 

[Analog]

The peak voltage of 110VAC is 155V. If it rises to 120V then the peak voltage is 170V. Spikes might increase the peak to 380V.
A 1N4001 has a max allowed voltage of only 50V. Use 1N4004 diodes rated at 400V.

Look at the datasheet for a 7805. Texas Instruments recommends a max input of 25V. Of course the voltage across it times the current through it determines how hot it will get.

I agree with all that audioguru has mentioned, but you are not rectifying the mains directly, you are using a step down transformer, so the voltages mentioned will be substantially lower. Regardless, it would be better to over engineer the bridge, even if the 4001s work.

 

[Roff]

I agree with all that audioguru has mentioned, but you are not rectifying the mains directly, you are using a step down transformer, so the voltages mentioned will be substantially lower. Regardless, it would be better to over engineer the bridge, even if the 4001s work.

I must have missed the part about the step down transformer. Was it in another thread?

 

[Oblong]

" I must have missed the part about the step down transformer. Was it in another thread?"

Feeding a 7805 directly with rectified and filtered line voltage would result in poof

I usually use 1n4002's or even 01's Depending on what my secondary is.

 

[audioguru]

He said he wanted to rectify the mains (170VDC) and feed it to a 7805.
He wanted to make smoke signals.

I don't think anybody uses 1N4001 rectifiers today. So the higher voltage ones are sold more and are less expensive.

 

[Leftyretro]

He said he wanted to rectify the mains (170VDC) and feed it to a 7805.
He wanted to make smoke signals.

I don't think anybody uses 1N4001 rectifiers today. So the higher voltage ones are sold more and are less expensive.

Well even after upgrading the rectifiers the poor 7805 would launch right off the board.

edit: Hum, I guess Ron said that already. Never mind, it's been raining steady and I have cabin fever.

Lefty

 

[Willbe]

He said he wanted to rectify the mains (170VDC) and feed it to a 7805.
He wanted to make smoke signals.

I don't think anybody uses 1N4001 rectifiers today. So the higher voltage ones are sold more and are less expensive.

Yes, whatever diode is cheaper and still meets specs. Specs don't make the $, it's supply and demand.

 

[RogerTango]

I should have mentioned, a step down xformer will be used.

Thanks to all-
Andrew

 

[mvs sarma]

I should have mentioned, a step down xformer will be used.

Thanks to all-
Andrew

Audioguru's comment is still valid.
there is no need to make two doors for cat and kitten as the old story went. 1N400x7 can be well used for most jobs whether you make a bridge for 9V Ac or 110 /220V AC. This helps need for ordering separately for low voltage needs. Otherwise, courier companies benefit.

 

[Analog]

glad I could help!