Hi! the other day I had my DVD player(Pioneer Dv-563A) unplug (RCA input)from my Gainclone LM3875 but.and I was listen to TV using my Gainclone and I hear sometimes like static from speakers.I started checking for the source where it came from(took me like two hrs)and I finally found that the output(RCA) had 48 volts AC. I touched the from RCA to chassis of my cable box and starting to hear static.is this possible that a chassis can get 48 volts AC? the DVD is playing fine but the chassis has 48 volts AC.and the DVD is not too old(14 months).so now I have to buy a new DVD,Lucky me!
What was the reference of the measurement.
10M insulation resistance (e.g. of a transformer) measured with a DMM of 10M input resistance will read half the voltage.
Gajanan Phadte
10M insulation resistance (e.g. of a transformer) measured with a DMM of 10M input resistance will read half the voltage.
Gajanan Phadte
Your chassis is floating (2 pin plug right) and you're measuring leakage current through DVM resistance (>10Mohm)
If you can find out why this current is flowing if you want to fix static. It could be something to do with the TV or cable connection or phases on the mains outlets.
Is it a problem when everything is plugged in?
If you can find out why this current is flowing if you want to fix static. It could be something to do with the TV or cable connection or phases on the mains outlets.
Is it a problem when everything is plugged in?
Well,I have a Isotel-6 Ultra surge protector and my Gainclone,Tv,DVD,satellite receiver are connected to it.right now I unplugged the DVD from AC.the satellite receiver has two plugs(power cord) and I measured from chassis to ground and I do not get any voltage but,when I connect the DVD player and I measure from chassis to ground,I get 48v AC.My Gainclone has three plugs(one is ground).but,I am sure the DVD payer is danger to keep it plugged in(I have children).so that is why I have it unplugged and soon I will have to get a new one with no voltage on the chassis lol.
AC on Chassis
Guys
What you are seeing is normal from a pice of equipment using an SMPS PSU. On a 240V DVD Player STB etc, this figure can be as high as 120VAC. All of these SMPS powered devices have a special high voltage capacitor between the mains side and the "earth" of the player RCA sockets etc. You will get a "bite" when plugging in to an earthed preamp or power amplifier, whether switched on or not. I brought this up in the "Destroyer" thread a little while back.
SandyK
Guys
What you are seeing is normal from a pice of equipment using an SMPS PSU. On a 240V DVD Player STB etc, this figure can be as high as 120VAC. All of these SMPS powered devices have a special high voltage capacitor between the mains side and the "earth" of the player RCA sockets etc. You will get a "bite" when plugging in to an earthed preamp or power amplifier, whether switched on or not. I brought this up in the "Destroyer" thread a little while back.
SandyK
But,where should I get the ground from?.if the power cord is just two plugs.is it safe to do it like that?something is wrong for sure!.
AC on Chassis Post #7
Guys
What you are seeing is normal from a piece of equipment using an SMPS PSU. On a 240V DVD Player STB etc, this figure can be as high as 120VAC. All of these SMPS powered devices have a special high voltage capacitor between the mains side and the "earth" of the player RCA sockets etc. You will get a "bite" when plugging in to an earthed preamp or power amplifier, whether switched on or not. I brought this up in the "Destroyer" thread a little while back.
SandyK.
Well Sandyk. if this is "normal" to get 48v AC,this is the first time that I hear a"chassis" getting a voltage!who ever design this piece of junk,should be shot!. that is for sure.
Guys
What you are seeing is normal from a piece of equipment using an SMPS PSU. On a 240V DVD Player STB etc, this figure can be as high as 120VAC. All of these SMPS powered devices have a special high voltage capacitor between the mains side and the "earth" of the player RCA sockets etc. You will get a "bite" when plugging in to an earthed preamp or power amplifier, whether switched on or not. I brought this up in the "Destroyer" thread a little while back.
SandyK.
Well Sandyk. if this is "normal" to get 48v AC,this is the first time that I hear a"chassis" getting a voltage!who ever design this piece of junk,should be shot!. that is for sure.
AC on Chassis
DV563A SMPS - This is typical. THe AC voltage is at very low current and not dangerous. It may however cause a small hum on it's input of an earthed preamp/poweramp.
SandyK
DV563A SMPS - This is typical. THe AC voltage is at very low current and not dangerous. It may however cause a small hum on it's input of an earthed preamp/poweramp.
SandyK
An externally hosted image should be here but it was not working when we last tested it.
AC on chassis
Guys
Sorry, but we will all have to learn to live with it !
SMPS PSUs have been mandated by EU, as well as the state of California, to replace linear PSUs. It will be world wide soon, like it or not !
Blame the "greenies" !
SandyK
BTW, My Oppo DV981HD DVD-A/SACD player , which works on 240VAC, readsa approx 82VAC to earth.
Guys
Sorry, but we will all have to learn to live with it !
SMPS PSUs have been mandated by EU, as well as the state of California, to replace linear PSUs. It will be world wide soon, like it or not !
Blame the "greenies" !
SandyK
BTW, My Oppo DV981HD DVD-A/SACD player , which works on 240VAC, readsa approx 82VAC to earth.
Sandyk! is it against the law lol! to get a "hot"chassis.48vAC is something!.next time I buy one, I will bring my Multimeter with me lol.that way I will be sure I do not get any voltage on chassis.
Sandyk! but,this 48volts AC,will this voltage damage my Gainclone?,any damage or bad things to my Gainclone?.here we use 120 AC.
because,I would rader put it in the garbage if it will damage the sound or damage my Gainclone.
because,I would rader put it in the garbage if it will damage the sound or damage my Gainclone.
AC on Chassis
lanchile07
Lots of luck. I doubt that you will be readily able to buy a DVD player etc that isn't using an SMPS supply. All the linear PSU ones will be phased out, if they haven't been already. The problem even extends now to headphone amplifiers, where a talented English designer had to start using SMPS plug packs, and had a few similar reports to yours. Sometimes you could feel a "vibration" if you rubbed your fingers across the unit's metal case.
SandyK
lanchile07
Lots of luck. I doubt that you will be readily able to buy a DVD player etc that isn't using an SMPS supply. All the linear PSU ones will be phased out, if they haven't been already. The problem even extends now to headphone amplifiers, where a talented English designer had to start using SMPS plug packs, and had a few similar reports to yours. Sometimes you could feel a "vibration" if you rubbed your fingers across the unit's metal case.
SandyK
AC on chassis
lanchile07
No damage will result. As I said previously, it is due to the very
small current flowing through that capacitor,which I highlighted in red, on the attachment. You may feel a tingle when plugging in to an earthed preamp etc, but it is not dangerous. Some linear PSU devices also have a small AC voltage present between them and earth. My old S-VHS recorder had >3VAC to earth. I used to notice a "bite" when plugging in leads or antenna.
SandyK
lanchile07
No damage will result. As I said previously, it is due to the very
small current flowing through that capacitor,which I highlighted in red, on the attachment. You may feel a tingle when plugging in to an earthed preamp etc, but it is not dangerous. Some linear PSU devices also have a small AC voltage present between them and earth. My old S-VHS recorder had >3VAC to earth. I used to notice a "bite" when plugging in leads or antenna.
SandyK
Sandyk,but why now they use "SMPS supply"?
is it better to have voltage on the chassis?.
what is going on?maybe who ever invented this "new" way,does not have kids!.
is it better to have voltage on the chassis?.
what is going on?maybe who ever invented this "new" way,does not have kids!.
Thank you Sandyk!
Thank you Sandyk! for you time explaining the AC chassis question. just in case if you do not see me here anymore,you know where I am going to be... "heaven".lol
Thank you Sandyk! for you time explaining the AC chassis question. just in case if you do not see me here anymore,you know where I am going to be... "heaven".lol
AC on chassis
lanchile07
As I said previously, it is at such a low current that it is harmless.
SMPS supplies have been mandated by legislation to help reduce power consumption, and thus, greenhouse gas emissions.
These supplies will also soon all be intelligent, and adjust themselves to the actual current demands. This will make all of these players ,STBs etc ,much more energy efficient.
It's just like some countries have recently legislated to ban incandescent lighting in favour of Energy Saver lamps.
I don't particularly like them either, but that's what we all have to look forward to.
SandyK
lanchile07
As I said previously, it is at such a low current that it is harmless.
SMPS supplies have been mandated by legislation to help reduce power consumption, and thus, greenhouse gas emissions.
These supplies will also soon all be intelligent, and adjust themselves to the actual current demands. This will make all of these players ,STBs etc ,much more energy efficient.
It's just like some countries have recently legislated to ban incandescent lighting in favour of Energy Saver lamps.
I don't particularly like them either, but that's what we all have to look forward to.
SandyK
Thank you!
Now,I understand!.you were so kind explaining everything I was looking for.clear as my Gainclone lol.thank you so much for all your help.
PS: My Gainclone will never have any kind of voltage on the chassis.lol
Now,I understand!.you were so kind explaining everything I was looking for.clear as my Gainclone lol.thank you so much for all your help.
PS: My Gainclone will never have any kind of voltage on the chassis.lol
don't blame the 'greenies' !
Manufacturers are free to reduce the standby-losses by other means.
Build in real, easy accessible, power switches or adding an additional standby power supply should be possible.
But smps are cheap...😀
regards
Manufacturers are free to reduce the standby-losses by other means.
Build in real, easy accessible, power switches or adding an additional standby power supply should be possible.
But smps are cheap...😀
regards
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