Challenge of Voltage/Digital standards differences between USA and Asia

[watours]

Hello, I recently moved from USA to Singapore and my love for my 5 year old 65 inch plasma TV forced me to bring it along with me. After doing a lot of research, I thought I had covered all bases to address the voltage and digital standards differences between the 2 countries but every time i connect a local set-top-box to my TV via HDMI, my apartment's circuit breaker keeps tripping.

I bought a step down transformer (220->110 V) and PAL->NTSC converter and here are the steps I followed:

1. Connected step down transformer to Main Supply (220v) - > ok
2. Connected TV to transformer (110v) - > ok (tv switched on)
3. Connected Apple Tv (from US) to Main Supply (220v) - > ok (apple supports 110-220v)
4. Connected Apple Tv (from US) to TV via HDMI - > ok (works)
5. Connected Local Set-top box (from Singapore) to Main supply (220v) - > ok (powers up)
And Finally,
6. Connected Local Set-top box (from Singapore) to TV via HDMI -> circuit breaker trips

I cannot seem to understand what goes wrong every time i connect the set-top box to the TV. They have replaced the set-top-box with another but the issue still remains. I have tried plugging the set-top box to the converter (it supports 110-220v) and then connect to the TV but the issue still remains. Can anyone shed any light on how I investigate or fix this? Are there different HDMI standards in different regions? Any help will be greatly apprciated.

 

[davenn]

Can anyone shed any light on how I investigate or fix this? Are there different HDMI standards in different regions? Any help will be greatly appreciated.

hi there
welcome to EP

There may be a difference in grounding between the US and the local products ... maybe along the lines of how the neutral line and the ground interact

As far as I'm aware, HDMI is a worldwide standard

when the HDMI cable is connected and it causes the hassle. It's telling me that the chassis ground in the STB is at a different potential to the chassis ground in the TV

Dave

 

[Bluejets]

Is the "circuit breaker" tripping on overcurrent or on earth leakage (big difference).

 

[watours]

thanks for the quick reply davenn. Is there a way to verify that the problem is the different ground levels between the TV/STB. and if so, are there ways to correct it without blowing stuff up

 

[watours]

Is the "circuit breaker" tripping on overcurrent or on earth leakage (big difference).

thanks bulejets, is there a way to diagnose the problem?

 

[Bluejets]

Assuming it is neutral current from the isolated supply returning through the toroid on an earth leakage type breaker............
Yes but I doubt you would be able to follow the details or have the necessary equipment to do so.

 

[Harald Kapp]

I suspect a ground loop via Apple-TV ... TV ... Set-top box. As the Apple TV and the Set-top box are both directly connected to mains, stray capacitances (or intentional capacitors for EMC purposes) may create an AC ground loop triggering the RCD in you mains wiring.
Check this by disconnecting the Apple TV from the TV (or from mains). Or connect the apple TV to the transformer, too.

 

[watours]

I suspect a ground loop via Apple-TV ... TV ... Set-top box. As the Apple TV and the Set-top box are both directly connected to mains, stray capacitances (or intentional capacitors for EMC purposes) may create an AC ground loop triggering the RCD in you mains wiring.
Check this by disconnecting the Apple TV from the TV (or from mains). Or connect the apple TV to the transformer, too.

Removed the Apple tv and even when both, TV and STB, are getting their power from the same Step down transformer, the circuitbreaker still trips when i connect the two through an HDMI cable.

 

[shrtrnd]

Some people say it doesn't matter, but along with everything else, the US uses 60hz, and the parts of Asia I've been
to use 50Hz. All of the above comments are valid, I'm just throwing one more issue at you.
I'll also mention, the standards for the use of digital material are zoned differently for the US and Asia. Discs sold
where you are now, will not play on products produced for use in the US market. You may be running into issues due to that.
I'd be Googleing information on the differences, which may be interfering with your troubleshooting methods.

 

[Harald Kapp]

I'll also mention, the standards for the use of digital material are zoned differently for the US and Asia. Discs sold

This should not cause a trigger of the circuit breaker, though.

Removed the Apple tv and even when both, TV and STB, are getting their power from the same Step down transformer, the circuitbreaker still trips when i connect the two through an HDMI cable.

Could you, just for the purpose of testing, use two separate step down transformers?

 

[davenn]

Removed the Apple tv and even when both, TV and STB, are getting their power from the same Step down transformer, the circuitbreaker still trips when i connect the two through an HDMI cable.

Some people say it doesn't matter, but along with everything else, the US uses 60hz, and the parts of Asia I've been
to use 50Hz. All of the above comments are valid, I'm just throwing one more issue at you.
I'll also mention, the standards for the use of digital material are zoned differently for the US and Asia. Discs sold
where you are now, will not play on products produced for use in the US market. You may be running into issues due to that.
I'd be Googleing information on the differences, which may be interfering with your troubleshooting methods.

neither of those would be causing this problem

I still go with my comments in post #2 and bluejets comment in post #6
And this comment of his is very valid ....

Yes but I doubt you would be able to follow the details or have the necessary equipment to do so.

@watours, if you really want to use this gear, you will probably have to employ an electronics tech to sort it out for you ... either that or buy a local TV

Dave

 

[shrtrnd]

I've been spanked.
I thought I was adding additional comments that watours might or might not have been aware of.
I did not stick to the main failure he described.
The main problem was fuse blowing, and I took it for granted that, that particular issue was being addressed by
other posts here.
My comments were intended to make watours aware, if he was not, that the digital standards between the US
and Asia are different. And that if (after solving the fuse problem), he tried to view media not compliant with his
US market model, he'd still think he had an electronic problem, and not a one of standards.
Harald might appreciate this. A guy sold me a box of German movies that looked pretty good to me.
Unfortunately, I found out the hard way they were coded for the European market, and I can't view them on
my US player.

 

[davenn]

I've been spanked.
I thought I was adding additional comments that watours might or might not have been aware of.
I did not stick to the main failure he described.
The main problem was fuse blowing, and I took it for granted that, that particular issue was being addressed by
other posts here.
My comments were intended to make watours aware, if he was not, that the digital standards between the US
and Asia are different. And that if (after solving the fuse problem), he tried to view media not compliant with his
US market model, he'd still think he had an electronic problem, and not a one of standards.
Harald might appreciate this. A guy sold me a box of German movies that looked pretty good to me.
Unfortunately, I found out the hard way they were coded for the European market, and I can't view them on
my US player.

all good, no probs

 

[watours]

This should not cause a trigger of the circuit breaker, though.
Could you, just for the purpose of testing, use two separate step down transformers?

Unfortunately i have only 1 step down at the moment; but i have noticed another interesting quirk. I have connected my step down transformer to a fancy belkin surge protector that i have been using for some time. It has two indicators that read "Protected" and "Not Grounded".

I noticed that the "Not Grounded" LED glows up when i connect the surge protector to the step down transformer; However, when i connect the surge protector directly to the mains, the "Not Grounded" light stays off. It seems to me that the transformer is somehow screwing up the grounding voltage and it might be causing issues. So I had a couple of questions that i hope you guys can guide me on:

1. Seeing the "Not Grounded" LED behavior, does it make sense to buy another transformer that does not have the grounding problem?
2. Assuming the transformer is the problem, why would my Apple TV work (through HDMI) when its connected to main supply? shouldn't it face the same problem as the STB?

 

[(*steve*)]

It sounds like your step down transformer is either an isolating transformer WITHOUT the earth connection being maintained, or possibly that you are using a plug somewhere that can be connected either way around and that you have an autotransformer which is connected so that neutral is not connected straight through.

 

[Harald Kapp]

Unfortunately, I found out the hard way they were coded for the European market, and I can't view them on
my US player.

That works the other way round, too. To circumvent this, a PC with a region code free DVD player can be used to play back these movies. The region code of a PC DVD drive can be set a few times (afaik max. 5, at least on older drives). You'd need two drives, one set for region 1, the other for region 2 to be able to play back both types of DVDs on your PC.

It sounds like your step down transformer is either an isolating transformer WITHOUT the earth connection being maintained, or possibly that you are using a plug somewhere that can be connected either way around and that you have an autotransformer which is connected so that neutral is not connected straight through.

@watours : Do you have a multimeter? In your original setup, without actually connecting the HDMI cable from the set top box to the TV, measure the voltage differential between the TV's ground (chassis) and the set top box's ground (e.g. the metallic shiled of teh HDMI cable not plugged into the TV). Set the multimeter to high voltage (e.g. 1000 V AC). If you see mains voltage (230 V), you definitely have an issue with grounding. Try pluging the various plugs in a 180 ° rotated position. Is there a setup where the voltage difference vanishes? You may be able to use this configuration. I do not recommend this as a permanent solution as any change of the plug configuration can make the problem appear again.
A proper grounding scheme would be required. This may or may not involve getting a new step-down transformer (not the auto-transformer type). Of course, buying a new TV may be the easier way.

 

[shrtrnd]

Thanks for the tip Harald (Again, though not a part of watours original post).
I really do want to see these movies I bought. They appear to be good movies that I had not heard of before.

 

[watours]

It sounds like your step down transformer is either an isolating transformer WITHOUT the earth connection being maintained, or possibly that you are using a plug somewhere that can be connected either way around and that you have an autotransformer which is connected so that neutral is not connected straight through.

I suspect a ground loop via Apple-TV ... TV ... Set-top box. As the Apple TV and the Set-top box are both directly connected to mains, stray capacitances (or intentional capacitors for EMC purposes) may create an AC ground loop triggering the RCD in you mains wiring.
Check this by disconnecting the Apple TV from the TV (or from mains). Or connect the apple TV to the transformer, too.

hi there
welcome to EP

There may be a difference in grounding between the US and the local products ... maybe along the lines of how the neutral line and the ground interact

As far as I'm aware, HDMI is a worldwide standard

when the HDMI cable is connected and it causes the hassle. It's telling me that the chassis ground in the STB is at a different potential to the chassis ground in the TV

Dave

Thank you so much for your help; this problem has been fixed now. As it turns out, my step down was causing the problem. I got a new "high end" transformer and the entire setup works like magic now. Had to use the PAL to NTSC converter as well; the US tv didn't understand the refresh rate of this region.

once again, thank you so much for your help!

 

[davenn]

Thank you so much for your help; this problem has been fixed now. As it turns out, my step down was causing the problem. I got a new "high end" transformer and the entire setup works like magic now. Had to use the PAL to NTSC converter as well; the US tv didn't understand the refresh rate of this region.

once again, thank you so much for your help!

outstanding
good to hear