HDMI sparking - earth loop issue?

[jguk]

Hey,

Been trying to add a 37" Sharp TV and PS3 to an existing setup of 21" TV, HD recorder, VHS and digibox.

These are all powered from 2 double 13A wall sockets, with a couple of 3-way bricks and a trailing 4-way.

Initially I added the TV and connected it to the coaxial aerial, the HD recorder via HDMI and the digibox via composite video. All working fine, no problems at all, we watched the footy last night.

Then this morning I added the PS3, connected the PS3 power cable and the HDMI into the back of the PS3 and then went to connect the HDMI to the TV's 2nd HDMI socket. I noticed that when the metal sleeve of the HDMI cable touched the metal chassis of the TV (around the TV connectors etc) there was some small blue/white sparks visible and audible. It smelled like my dads old train set.

Understandably I didn't want to plug the HDMI cable into the TV for fear of damage, so I tried a few things to see what was going on:

- using a digital multimeter i measured the voltage between the TV chassis and the earth on the 13A 4-way - this was 19V AC.

- disconnecting all cables (bar power) to the TV reduced that to 13V AC

- voltage between the PS3's HDMI cable metal sleeve and the TV chassis was 19V AC

- voltage between the PS3's HDMI cable metal sleeve and the earth on the 4-way is zero.

- using a 13A extension with NO EARTH and plugging the PS3 into that prevented any sparking - so isolating the PS3 from the earth cures the problem.

So from that and some googling it must be some kind of earth problem... All the devices are not earthed (2 core mains cables), except the PS3 which has an earth, and according to the manual should be earthed.

I had no problems with the PS3 and TV in their previous location in another house.

Is this normal? Any ideas what I can do to fix this problem please?


Thanks,

James

 

[stef]

Hi jguk,
take your multimeter and measure the voltage between earth and neutral on your socket outlet,
also measure it with meter in ac and then in dc position. Is there a voltage potential present?

 

[jguk]

Hi Stef,

between Earth and Neutral on 13A 4-way there is no voltage in either AC or DC

between Earth and Live there is 246V on AC, nothing on DC (but it is a digital meter)


Thanks


James

 

[stef]

I just had a look at my PS3, it is a PS3 slim, two core mains lead, no earth. I suppose you have the
older model with 40GB hard drive ? As you say the fault comes when plugging in the HDMI from the
PS3 I suspect that the PS3 switch mode power supply has developed a fault. Can you check with
someone else's PS3 if the situation is the same then I don't know

 

[jguk]

I'm sure it's not a problem with the PS3, like I said I've never had an issue with it.

To me it seems like the PS3 is the only device with an earth and therefore whatever issues are in the aerial / electrics / pre-existing AV devices are being earthed through the PS3 and its HDMI cable.

Might need to do some more testing on the existing setup, if anyone has any suggestions?


James

 

[nickblake]

Most appliances IE TVs video PS ,DVD's Free views are what is called class 2 and are double insulated ,they dont require an earth from the supply ,they use the Ov of the power supply to earth the chasis of the appliance , to prevent damage all appliance should be disconnected from the supply prior to swapping on inserting plugs etc , its is possible that the sparks that were seen we static charges ,or from an earth that has a lower potential than the chasis of the appliance

 

[anton1210]

I'm sure it's not a problem with the PS3, like I said I've never had an issue with it.

To me it seems like the PS3 is the only device with an earth and therefore whatever issues are in the aerial / electrics / pre-existing AV devices are being earthed through the PS3 and its HDMI cable.

Might need to do some more testing on the existing setup, if anyone has any suggestions?


James

just because you havent had any 'issues' before, it doesnt mean you havent had an earth leakage on the PS3, as it would not effect its performance, and would not trip at the board unless you had an RCD.

 

[jguk]

True, but what I mean is I've had this unit for 3 years and plugged it (and hot plugged it) into numerous TVs and various other equipment and never seen sparks like I've seen today.

Of course, if I had plugged in the HDMI first and then the power cable I probably never would have noticed the issue - assuming of course that the voltage differential wouldn't have fried the HDMI ports, and that the ground issue wouldn't have affected its use.

So unless it's spontaneously developed a fault in the last 24 hours i think the problem lies with the setup / wiring / combination of devices in this location.

Will move it around and test in other rooms, see if I can figure it out.

 

[jguk]

Most appliances IE TVs video PS ,DVD's Free views are what is called class 2 and are double insulated ,they dont require an earth from the supply ,they use the Ov of the power supply to earth the chasis of the appliance , to prevent damage all appliance should be disconnected from the supply prior to swapping on inserting plugs etc , its is possible that the sparks that were seen we static charges ,or from an earth that has a lower potential than the chasis of the appliance

Heya,

Don't think it was static as there was no indication that the charge or sparks were dissipating, just a steady voltage differential like a train set short (albeit much, much lower power)

So if it's an earth potential thing - is it a problem? Am I going to fry my HDMI ports? should I unplug everything, connect the HDMI and then replug and power up, fingers crossed?

Or is there a practical solution?


Cheers,

James