Forums

Power supply for Buck dc-dc

Started by Unknown January 10, 2013
Hi,
Please, could I use a half-bridge diode circuit to power this buck power supply ?
http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-power-supply-module-/190649685203?pt=LH_DefaultDomain_0&hash=item2c639b54d3

This power supply accepts 62VDC input, so if I use one  rectifier diode to rectify 
120Vac home's power (decay to ~ 54Vdc), it will work ? 

120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. 
Thanks.
<contracer11@gmail.com>
> > Please, could I use a half-bridge diode circuit to power this buck power > supply ? > > http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-power-supply-module-/190649685203?pt=LH_DefaultDomain_0&hash=item2c639b54d3 > > This power supply accepts 62VDC input, so if I use one rectifier diode to > rectify > 120Vac home's power (decay to ~ 54Vdc), it will work ?
** No way.
> 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply.
** Your math is all screwy. 120VAC > 170V peak - so that will be the DC output voltage after one diode and a filter cap. PLUS - you have NO SAFETY ISOLATION !!!! For most applications, such a set up would be LETHAL !! Forget it. ..... Phil
On Thu, 10 Jan 2013 19:02:04 -0800, contracer11 wrote:

> Hi, > Please, could I use a half-bridge diode circuit to power this buck power > supply ? > http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-
power-supply-module-/190649685203? pt=LH_DefaultDomain_0&hash=item2c639b54d3
> > This power supply accepts 62VDC input, so if I use one rectifier diode > to rectify 120Vac home's power (decay to ~ 54Vdc), it will work ? > > 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. Thanks.
Oi. Wrong in so many ways. Where should we start? The short answer is, given what you know, don't even try. Learn more about electronics first, then start playing with power from the wall when you're not going to kill yourself, burn your house down, or shock your kids silly. If you don't understand why you can't connect your equipment straight to the wall power without isolation, then you need to learn more about electronics and about how houses are wired for power before you can safely proceed to play with 120V. While it isn't always instantly LETHAL!!!, getting a shock from 120V always hurts a lot, it _can_ kill you on a bad day, and there's a lot of ways that you can build your equipment so that it doesn't kill you or your loved ones, but still burns down your house. Get yourself a copy of the ARRL manual. They've got whole chapters in there on power supply design, electric safety, how houses in North America are wired, and all that useful stuff. Then READ IT. If you don't feel you understand what it says, don't mess around with 120V -- just find a wall-wart that delivers what you need, and be happy. -- My liberal friends think I'm a conservative kook. My conservative friends think I'm a liberal kook. Why am I not happy that they have found common ground? Tim Wescott, Communications, Control, Circuits & Software http://www.wescottdesign.com
On Friday, January 11, 2013 4:05:27 AM UTC-2, Tim Wescott wrote:
> On Thu, 10 Jan 2013 19:02:04 -0800, contracer11 wrote: > > > > > Hi, > > > Please, could I use a half-bridge diode circuit to power this buck power > > > supply ? > > > http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant- > > power-supply-module-/190649685203? > > pt=LH_DefaultDomain_0&hash=item2c639b54d3 > > > > > > This power supply accepts 62VDC input, so if I use one rectifier diode > > > to rectify 120Vac home's power (decay to ~ 54Vdc), it will work ? > > > > > > 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. Thanks. > > > > Oi. Wrong in so many ways. Where should we start? > > > > The short answer is, given what you know, don't even try. Learn more > > about electronics first, then start playing with power from the wall when > > you're not going to kill yourself, burn your house down, or shock your > > kids silly. > > > > If you don't understand why you can't connect your equipment straight to > > the wall power without isolation, then you need to learn more about > > electronics and about how houses are wired for power before you can > > safely proceed to play with 120V. While it isn't always instantly > > LETHAL!!!, getting a shock from 120V always hurts a lot, it _can_ kill > > you on a bad day, and there's a lot of ways that you can build your > > equipment so that it doesn't kill you or your loved ones, but still burns > > down your house. > > > > Get yourself a copy of the ARRL manual. They've got whole chapters in > > there on power supply design, electric safety, how houses in North > > America are wired, and all that useful stuff. Then READ IT. If you > > don't feel you understand what it says, don't mess around with 120V -- > > just find a wall-wart that delivers what you need, and be happy. > > > > -- > > My liberal friends think I'm a conservative kook. > > My conservative friends think I'm a liberal kook. > > Why am I not happy that they have found common ground? > > > > Tim Wescott, Communications, Control, Circuits & Software > > http://www.wescottdesign.com
Yesterday I took my digital multimeter, insert a 1N4007 diode in power's home, and I got 52Vdc from that !
On 11/01/2013 11:36, contracer11@gmail.com wrote:
> On Friday, January 11, 2013 4:05:27 AM UTC-2, Tim Wescott wrote: >> On Thu, 10 Jan 2013 19:02:04 -0800, contracer11 wrote: >>
>> >> Oi. Wrong in so many ways. Where should we start? >> >> The short answer is, given what you know, don't even try. Learn >> more about electronics first, then start playing with power from >> the wall when you're not going to kill yourself, burn your house >> down, or shock your kids silly. >> >> If you don't understand why you can't connect your equipment >> straight to the wall power without isolation, then you need to >> learn more about electronics and about how houses are wired for >> power before you can safely proceed to play with 120V. While it >> isn't always instantly LETHAL!!!, getting a shock from 120V always >> hurts a lot, it _can_ kill you on a bad day, and there's a lot of >> ways that you can build your equipment so that it doesn't kill you >> or your loved ones, but still burns down your house. >> >> Get yourself a copy of the ARRL manual. They've got whole chapters >> in there on power supply design, electric safety, how houses in >> North America are wired, and all that useful stuff. Then READ IT. >> If you don't feel you understand what it says, don't mess around >> with 120V -- just find a wall-wart that delivers what you need, and >> be happy. >> > > Yesterday I took my digital multimeter, insert a 1N4007 diode in > power's home, and I got 52Vdc from that ! >
Tim is right. When you understand why you measure 52VDC with your digital multimeter you'll be in much safer position to move forward. -- Mike Perkins Video Solutions Ltd www.videosolutions.ltd.uk
On Friday, January 11, 2013 1:02:04 AM UTC-2, contr...@gmail.com wrote:
> Hi, >=20 > Please, could I use a half-bridge diode circuit to power this buck power =
supply ?
>=20 > http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-po=
wer-supply-module-/190649685203?pt=3DLH_DefaultDomain_0&hash=3Ditem2c639b54= d3
>=20 >=20 >=20 > This power supply accepts 62VDC input, so if I use one rectifier diode t=
o rectify=20
>=20 > 120Vac home's power (decay to ~ 54Vdc), it will work ?=20 >=20 >=20 >=20 > 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply.=20 >=20 > Thanks.
Is there any way to bypass transformer=B4s usage to power this buck ? It=B4s only for school work, not for real usage...
On Jan 11, 6:36=A0am, contrace...@gmail.com wrote:
> On Friday, January 11, 2013 4:05:27 AM UTC-2, Tim Wescott wrote: > > On Thu, 10 Jan 2013 19:02:04 -0800, contracer11 wrote: > > > > Hi, > > > > Please, could I use a half-bridge diode circuit to power this buck po=
wer
> > > > supply ? > > > >http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant=
-
> > > power-supply-module-/190649685203? > > > pt=3DLH_DefaultDomain_0&hash=3Ditem2c639b54d3 > > > > This power supply accepts 62VDC input, so if I use one =A0rectifier d=
iode
> > > > to rectify 120Vac home's power (decay to ~ 54Vdc), it will work ? > > > > 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. Than=
ks.
> > > Oi. =A0Wrong in so many ways. =A0Where should we start? > > > The short answer is, given what you know, don't even try. =A0Learn more > > > about electronics first, then start playing with power from the wall wh=
en
> > > you're not going to kill yourself, burn your house down, or shock your > > > kids silly. > > > If you don't understand why you can't connect your equipment straight t=
o
> > > the wall power without isolation, then you need to learn more about > > > electronics and about how houses are wired for power before you can > > > safely proceed to play with 120V. =A0While it isn't always instantly > > > LETHAL!!!, getting a shock from 120V always hurts a lot, it _can_ kill > > > you on a bad day, and there's a lot of ways that you can build your > > > equipment so that it doesn't kill you or your loved ones, but still bur=
ns
> > > down your house. > > > Get yourself a copy of the ARRL manual. =A0They've got whole chapters i=
n
> > > there on power supply design, electric safety, how houses in North > > > America are wired, and all that useful stuff. =A0Then READ IT. =A0If yo=
u
> > > don't feel you understand what it says, don't mess around with 120V -- > > > just find a wall-wart that delivers what you need, and be happy. > > > -- > > > My liberal friends think I'm a conservative kook. > > > My conservative friends think I'm a liberal kook. > > > Why am I not happy that they have found common ground? > > > Tim Wescott, Communications, Control, Circuits & Software > > >http://www.wescottdesign.com > > Yesterday I took my digital multimeter, insert a 1N4007 diode in power's =
home, and I got 52Vdc from that !- Hide quoted text -
> > - Show quoted text -
That makes no sense to me. Have you been zapped by 120 Vac yet? Keep one hand in your pocket. You can buy a nice linear power supply from Mastek ~50V @3A for a bit more than $100. George H.
On a sunny day (Fri, 11 Jan 2013 06:41:26 -0800 (PST)) it happened
contracer11@gmail.com wrote in
<012a44f1-f4e8-4503-a682-e0030c467f35@googlegroups.com>:

>On Friday, January 11, 2013 1:02:04 AM UTC-2, contr...@gmail.com wrote: >> Hi, >> >> Please, could I use a half-bridge diode circuit to power this buck power = >supply ? >> >> http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-po= >wer-supply-module-/190649685203?pt=LH_DefaultDomain_0&hash=item2c639b54= >d3 >> >> >> >> This power supply accepts 62VDC input, so if I use one rectifier diode t= >o rectify >> >> 120Vac home's power (decay to ~ 54Vdc), it will work ? >> >> >> >> 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. >> >> Thanks. > > >Is there any way to bypass transformer&acute;s usage to power this buck ? >It&acute;s only for school work, not for real usage...
No. And if you single phase rectify 120V AC you still get 120 /2 * sqrt(2) = 85 V DC peak. Add some for main tolerances. And you would not be insolated form mains.
On Fri, 11 Jan 2013 15:29:24 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>On a sunny day (Fri, 11 Jan 2013 06:41:26 -0800 (PST)) it happened >contracer11@gmail.com wrote in ><012a44f1-f4e8-4503-a682-e0030c467f35@googlegroups.com>: > >>On Friday, January 11, 2013 1:02:04 AM UTC-2, contr...@gmail.com wrote: >>> Hi, >>> >>> Please, could I use a half-bridge diode circuit to power this buck power = >>supply ? >>> >>> http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-po= >>wer-supply-module-/190649685203?pt=LH_DefaultDomain_0&hash=item2c639b54= >>d3 >>> >>> >>> >>> This power supply accepts 62VDC input, so if I use one rectifier diode t= >>o rectify >>> >>> 120Vac home's power (decay to ~ 54Vdc), it will work ? >>> >>> >>> >>> 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. >>> >>> Thanks. >> >> >>Is there any way to bypass transformer&acute;s usage to power this buck ? >>It&acute;s only for school work, not for real usage... > >No.
--- Right. ---
>And if you single phase rectify 120V AC you still get 120 /2 * sqrt(2) = 85 V DC peak.
--- No, you get 120 * sqrt(2) = 170VDC, but you'll need twice the capacitance for the same ripple you'd get with full-wave rectification. -- JF
On a sunny day (Fri, 11 Jan 2013 09:56:17 -0600) it happened John Fields
<jfields@austininstruments.com> wrote in
<q0d0f899un8imu5cihpgocapvp2p0vcaq7@4ax.com>:

>On Fri, 11 Jan 2013 15:29:24 GMT, Jan Panteltje ><pNaonStpealmtje@yahoo.com> wrote: > >>On a sunny day (Fri, 11 Jan 2013 06:41:26 -0800 (PST)) it happened >>contracer11@gmail.com wrote in >><012a44f1-f4e8-4503-a682-e0030c467f35@googlegroups.com>: >> >>>On Friday, January 11, 2013 1:02:04 AM UTC-2, contr...@gmail.com wrote: >>>> Hi, >>>> >>>> Please, could I use a half-bridge diode circuit to power this buck power = >>>supply ? >>>> >>>> http://www.ebay.com/itm/ZXY6005-DC-DC-60V-voltage-and-current-constant-po= >>>wer-supply-module-/190649685203?pt=LH_DefaultDomain_0&hash=item2c639b54= >>>d3 >>>> >>>> >>>> >>>> This power supply accepts 62VDC input, so if I use one rectifier diode t= >>>o rectify >>>> >>>> 120Vac home's power (decay to ~ 54Vdc), it will work ? >>>> >>>> >>>> >>>> 120Vac -> 1 rectifier diode -> 54Vdc -> Buck DC-DC power supply. >>>> >>>> Thanks. >>> >>> >>>Is there any way to bypass transformer&acute;s usage to power this buck ? >>>It&acute;s only for school work, not for real usage... >> >>No. > >--- >Right. >--- > >>And if you single phase rectify 120V AC you still get 120 /2 * sqrt(2) = 85 V DC peak. > >--- >No, you get 120 * sqrt(2) = 170VDC, but you'll need twice the >capacitance for the same ripple you'd get with full-wave >rectification.
Oops! I must be getting old.... Thanks for the correction... :-)