Receiving a mild shock in AVR

[Love4sound]

I have been observing the same from my Onkyo TX AV receiver for quite a while over the past year. I think its an earthing issue as the plug for the power supply is a 2-pin plug only.

However, I don't observes this with my Yamaha AS300 Amplifier at all which also has a 2-pin power plug

Is it intermittent ate every time you touch the avr there is a mild shock ?

 

[sahoork]

Dear Fm’s

Lately I noticed if I touch the top of my avr exactly at the vents with mild pressure I get an electric shock. What can be the reason? I have connected my avr to a vertex stabilizer.

Use RCCB 30ma(residual current) and check whether RCCB get tripped ( there is problem with earthing) also Measure neutral current it should be minimum zero is best.

 

[superczar]

These (very mild) shocks are on account of what is termed as a floating ground.
Most new AV devices use a two pronged connector - primarily because not having a third wire for earthing eliminates the chances of ground loops (that create noise and hums) altogether.

In absence of the earthing wire, some voltage differential will build up between the chassis and the rest of the circuit on account of the electromagnetic induction created within the circuits - the manifestatiom is typically greater for circuits operating at a high switching frequency (which is why HDMI connections are a typical culprit)
Normally this isn't a problem ...As long as the shock as you termed it is like a tingling sensation, it is almost always due to a floating ground.

As another FM advised, do put a high sensitivity RCCB when you can - as A) if the problem is something else (current leakage somewhere), the RCCB will trip and if it doesn't, you know you don't have a real problem
B) Despite being one of the most important safety devices one should use at home, RCCBs are surprisingly uncommon in India - everyone should install one for safety (and I don't mean safeguarding your AV equipment )

On a related note, Some people / forums (and electricians) will advise you to manually earth the device , esp devices with a metal chassis like your AVR - Do Not do that. Not only will you create the risk of ground loops but worse, may end up frying the video board on your AVR or TV

 

[VRavichandar]

If it is a two pin plug on the avr, try reversing it - this has helped in an electrical appliance.

 

[Love4sound]

These (very mild) shocks are on account of what is termed as a floating ground.
Most new AV devices use a two pronged connector - primarily because not having a third wire for earthing eliminates the chances of ground loops (that create noise and hums) altogether.

In absence of the earthing wire, some voltage differential will build up between the chassis and the rest of the circuit on account of the electromagnetic induction created within the circuits - the manifestatiom is typically greater for circuits operating at a high switching frequency (which is why HDMI connections are a typical culprit)
Normally this isn't a problem ...As long as the shock as you termed it is like a tingling sensation, it is almost always due to a floating ground.

As another FM advised, do put a high sensitivity RCCB when you can - as A) if the problem is something else (current leakage somewhere), the RCCB will trip and if it doesn't, you know you don't have a real problem
B) Despite being one of the most important safety devices one should use at home, RCCBs are surprisingly uncommon in India - everyone should install one for safety (and I don't mean safeguarding your AV equipment )

On a related note, Some people / forums (and electricians) will advise you to manually earth the device , esp devices with a metal chassis like your AVR - Do Not do that. Not only will you create the risk of ground loops but worse, may end up frying the video board on your AVR or TV

Yes it was just a mild tingling shock that I get when i feather touch the avr accidentally. I tried manually earthing but the speakers make a lot of crackling noise so removed it immediately. RCCB should be installed in the MCB?

 

[Love4sound]

Use RCCB 30ma(residual current) and check whether RCCB get tripped ( there is problem with earthing) also Measure neutral current it should be minimum zero is best.

Ok I will try this approach. Not heard of RCCB. Where should I connect it? In the MCB with an electrician or we can do it ourselves?

 

[TheAudioGuy]

Is it intermittent ate every time you touch the avr there is a mild shock ?

It occurs 80% of the time. Will try to make a mental note of ambient temperature and weather conditions next time it happens. Sometimes its unbearable and sometimes its very mild.

 

[Vivek Batra]

Ok I will try this approach. Not heard of RCCB. Where should I connect it? In the MCB with an electrician or we can do it ourselves?

This is the new device now days. Residual Current Circuit Breaker (RCCB). MCBs are bygone. This is installed the same way as MCB. I don't think you would gain anything by replacing MCB with RCCB. RCCBs are just more sensitive to current leakage.As another Fm suggested try matching the Netural and Live on the amp to the socket in wall or power strip.

 

[rsjaurr]

I too get very mild shock like tingling sensation when I touch my marantz 6013 which has two pin power plug.

It is inserted into custom made power extension board which is a dedicated line from distribution box with mcb.
This board also powers APC ups for oled tv.

Initially avr was connected to the surge only socket on the ups but I would still get same mild shock.

Crown xls 2502 is also connected to same extension board and i get tingling sensation from crown too.

Unfortunately I can not remove that extension board.

 

[Love4sound]

It occurs 80% of the time. Will try to make a mental note of ambient temperature and weather conditions next time it happens. Sometimes its unbearable and sometimes its very mild.

Ok I think you should have it checked.

 

[superczar]

Yes it was just a mild tingling shock that I get when i feather touch the avr accidentally. I tried manually earthing but the speakers make a lot of crackling noise so removed it immediately. RCCB should be installed in the MCB?

Ignore it .. It is not a problem
Do install a RCCB at the mains at the main circuit-breaker for an entirely different reason - to keep yourself and the family safe

 

[Love4sound]

Ignore it .. It is not a problem
Do install a RCCB at the mains at the main circuit-breaker for an entirely different reason - to keep yourself and the family safe

Sure will check with the electrician regarding the RCCB and ignore the avr mild shock for now

 

[Nitin K]

Sure will check with the electrician regarding the RCCB and ignore the avr mild shock for now

Hi Navin,

After getting the strong initial jolt of hearing the prices of AV equipment in India, all the other shocks given out by the equipment seem very minor and you get use to it.

Rgs,
Nitin

 

[Vivek Batra]

Hey Vivek

Thanks for confirming.Do let me know if installing a dedicated line helped.

Hi Navin

I still felt it last night. So dedicated line doesn't help either.

 

[Love4sound]

Hi Navin

I still felt it last night. So dedicated line doesn't help either.

Ok thanks for checking. Many fm’s confirmed they also get a mild shock time to time. Guess we have to live with it

 

[Vivek Batra]

Ok thanks for checking. Many fm’s confirmed they also get a mild shock time to time. Guess we have to live with it

True.

 

[balavignesh002]

@Love4sound please measure the volt of neutral and phase the same value you should receive when measured the volt with earth and phase.

If earth + phase volt is less significantly compared to neutral + phase, there is a grounding issue. Check for loose connection of ground wire. If connection good check if grounding post got dehydrated, you can check if earth improve by dehydrating the grounding post.

I recently used a vertex isolation transformer, which is 3 pin and I get 115 volt on ground + phase. And 250v on negative + phase.

My denon CDP and amp are 2 pin only so I didn't have any issue in it. But I got tickling shock on microwave oven, dishwasher fridge etc. I poured some 500 ml of water on the ground post. Now I get 230 on ground + phase. All my shock issues gone.

 

[Love4sound]

@Love4sound please measure the volt of neutral and phase the same value you should receive when measured the volt with earth and phase.

If earth + phase volt is less significantly compared to neutral + phase, there is a grounding issue. Check for loose connection of ground wire. If connection good check if grounding post got dehydrated, you can check if earth improve by dehydrating the grounding post.

I recently used a vertex isolation transformer, which is 3 pin and I get 115 volt on ground + phase. And 250v on negative + phase.

My denon CDP and amp are 2 pin only so I didn't have any issue in it. But I got tickling shock on microwave oven, dishwasher fridge etc. I poured some 500 ml of water on the ground post. Now I get 230 on ground + phase. All my shock issues gone.

Sure will check it. But for now I am not receiving any mild shocks haven’t done any changes but it’s all good now. Last week there was heavy thunder and rains can that have lead to the mild shocks ?

 

[Jupiter]

Sure will check it. But for now I am not receiving any mild shocks haven’t done any changes but it’s all good now. Last week there was heavy thunder and rains can that have lead to the mild shocks ?

Yeah in rainy season due to dampness i have also experience mild shock in various switches so maybe this is the reason

 

[Jupiter]

You have received the mild shock when you are touching the avr bare foot right

I have the same problem but with my air cooler i contacted local electrician he has done proper earthing after that i stopped receiving mild shock when touching it bare foot