Receiver shut off into 'protection mode' when I touched the metal door (static discharge from carpet) - Normal or potential electrical wiring issue?

[njweb]

Yesterday evening my 2 hour old (yes 2 hours!) Marantz SR7013 shut off / went into 'protection mode' when I touched its metal front panel door (forgot to touch the metal foot of the AV stand first) and I felt a static discharge (carpeted room and dry winter air). Ironically I usually make it a point to touch the AV stand first...

I was worried it might not turn on again. However to my huge relief, the power turned on right away when I touched the power button seconds later and it has been working fine since the incident - I ran it for hours afterwards and checked all my HDMI sources (BD player, TiVO and Roku) worked fine.

I read on another forum where someone else had a similar issue with an amp (although they also heard a loud pop from their speakers and some other odd behavior which was NOT the case for me):
Many members who replied to that post (about a Klasse amp) seemed to think that the amp going into protection mode was just due to static and that they also had static issues and they discharged themselves first before touching electronics gear (like I do), but two members thought that the amp going into protection mode was not just due to the static discharge and that there was likely another issue that cause it to actually go into protection mode, such as due to a wiring issue / electrical issue / ground fault issue in the home (although one might have also taken into account the speaker popping that the OP there had mentioned).

So my two questions about MY situation:
1)
a) it is a normal for a receiver (or amp etc.) to go into 'protection mode' and shut off when one's static is discharged into it (from me) after touching it?
OR
b) is a receiver or amp going into protection mode from one's static discharge alone NOT normal and possibly due to a wiring / electrical issue in the house?
2) Given this was a SINGLE incident and that everything is still working fine with my receiver after the incident (ran it for hours afterwards and also successfully tested / checked all my sources with it), should I be concerned about any potential of "hidden" damage or long term issues such as premature wear on components) that could surface years later?
Just trying to get peace of mind.

While I will leave the receiver panel closed (had only opened it to check something out on the display) and I almost always use the remote to control the receiver, so the likelihood of my touching the receiver again should be minimal, I still want to prevent this from happening again - maybe a ground / static discharge mat on top of the carpet in front of the receiver?

PS: IF the people who suggested that (b) above are right, I could call an electrician to check out the house wiring / electrical system (assuming there is no easy tool for me to test and see which outlet may have a loose wire e.g.). And I assume PSE&G will tell me to contact a private electrician.

 

[PENG]

So my two questions about MY situation:
1)
a) it is a normal for a receiver (or amp etc.) to go into 'protection mode' and shut off when one's static is discharged into it (from me) after touching it?

I wouldn't call it normal but obviously it could happen, and you found out the hard way.

OR
b) is a receiver or amp going into protection mode from one's static discharge alone NOT normal and possibly due to a wiring / electrical issue in the house?

No, It depends ore on what you walked on, and the protection scheme used by the unit. In your case, again, its obvious, such discharge triggered the protection mode. It may, however, be possible that your unit somehow had the sensing circuitry a little more sensitive than "normal/as intended by Marantz" but it is hard to know, only time will tell. If it happens a lot then I would say it is too sensitive and you should get the unit replaced.

2) Given this was a SINGLE incident and that everything is still working fine with my receiver after the incident (ran it for hours afterwards and also successfully tested / checked all my sources with it), should I be concerned about any potential of "hidden" damage or long term issues such as premature wear on components) that could surface years later?

Just trying to get peace of mind.

If it tripped instantaneously then I am confident to say "no" don't worry about damage. The static voltage could have been quite high and would likely have caused damage if you were actually touching a part that is prone to such high voltage damage such as certain IC chips, or even FETs, but you only touched the chassis, that somehow got sensed by the protective circuit.

 

[TLS Guy]

Yesterday evening my 2 hour old (yes 2 hours!) Marantz SR7013 shut off / went into 'protection mode' when I touched its metal front panel door (forgot to touch the metal foot of the AV stand first) and I felt a static discharge (carpeted room and dry winter air). Ironically I usually make it a point to touch the AV stand first...

I was worried it might not turn on again. However to my huge relief, the power turned on right away when I touched the power button seconds later and it has been working fine since the incident - I ran it for hours afterwards and checked all my HDMI sources (BD player, TiVO and Roku) worked fine.

I read on another forum where someone else had a similar issue with an amp (although they also heard a loud pop from their speakers and some other odd behavior which was NOT the case for me):
Many members who replied to that post (about a Klasse amp) seemed to think that the amp going into protection mode was just due to static and that they also had static issues and they discharged themselves first before touching electronics gear (like I do), but two members thought that the amp going into protection mode was not just due to the static discharge and that there was likely another issue that cause it to actually go into protection mode, such as due to a wiring issue / electrical issue / ground fault issue in the home (although one might have also taken into account the speaker popping that the OP there had mentioned).

So my two questions about MY situation:
1)
a) it is a normal for a receiver (or amp etc.) to go into 'protection mode' and shut off when one's static is discharged into it (from me) after touching it?
OR
b) is a receiver or amp going into protection mode from one's static discharge alone NOT normal and possibly due to a wiring / electrical issue in the house?
2) Given this was a SINGLE incident and that everything is still working fine with my receiver after the incident (ran it for hours afterwards and also successfully tested / checked all my sources with it), should I be concerned about any potential of "hidden" damage or long term issues such as premature wear on components) that could surface years later?
Just trying to get peace of mind.

While I will leave the receiver panel closed (had only opened it to check something out on the display) and I almost always use the remote to control the receiver, so the likelihood of my touching the receiver again should be minimal, I still want to prevent this from happening again - maybe a ground / static discharge mat on top of the carpet in front of the receiver?

PS: IF the people who suggested that (b) above are right, I could call an electrician to check out the house wiring / electrical system (assuming there is no easy tool for me to test and see which outlet may have a loose wire e.g.). And I assume PSE&G will tell me to contact a private electrician.

That can certainly happen. The static that builds up on your body in the winter on a nylon carpet, is thousands of volts. When discharged through delicate electronics, it can do permanent severe damage.

There is nothing wrong with your house wiring. But you got a warning to be very careful. You are lucky your receiver still works.

So I go the the expense of wool carpet in my AV room and not synthetics, and that helps a lot. I also have a central humidifier, and keep it to around 40%. That not only helps to prevent static, but is the sweet spot for discouraging the spread of infectious diseases.

Even so I try and remember to touch the grounded rack before any equipment. However, with this plan, so far I have had zero static events.

 

[njweb]

I wouldn't call it normal but obviously it could happen, and you found out the hard way.



No, It depends ore on what you walked on, and the protection scheme used by the unit. In your case, again, its obvious, such discharge triggered the protection mode. It may, however, be possible that your unit somehow had the sensing circuitry a little more sensitive than "normal/as intended by Marantz" but it is hard to know, only time will tell. If it happens a lot then I would say it is too sensitive and you should get the unit replaced.




If it tripped instantaneously then I am confident to say "no" don't worry about damage. The static voltage could have been quite high and would likely have caused damage if you were actually touching a part that is prone to such high voltage damage such as certain IC chips, or even FETs, but you only touched the chassis, that somehow got sensed by the protective circuit.

Just got home, so could not reply to thank you earlier.
Thanks a lot!

Regarding the "it depends on what you walked on": I walked on the Berber carpet (so definitely very conducive to static buildup occurring) in the basement; this, combined with the drier / dry winter air, contributed to the ESD event.
Agreed - If it starts to shut off every time, it may be too sensitive; or then again perhaps that is a great thing (it did not have a shutdown period and I was able to power it back on as soon as I pushed the power button.
In any case, the shutting off sensitivity being a bit too high (f that is the case) would not bother me, since I won't touch it often anyway (use the remote most of the time) and when I do touch it, I will try to never agai forget to discharge myself first - I usually touch the sturdy metal foot of the Sanus AV rack before touching my receiver).

Regarding your comment - "if it tripped instantly".... "being confident there is no permanent damage" - Thanks, that feedback gives me (extra) peace of mind!
Right, while 'instant' is a relative term since ESD can happen in nanoseconds (correct me if I am wrong all), it certainly tripped within a second of my touching it (and not later which would obviously be far more concerning), so I think that qualifies as "instant" in the sense you were referring to it.
And it did power up right away afterwards.

Finally, regarding this part - "The static voltage could have been quite high and would likely have caused damage if you were actually touching a part that is prone to such high voltage damage such as certain IC chips, or even FETs, but you only touched the chassis, that somehow got sensed by the protective circuit."
Thanks! Very useful information! I had read something quite similar earlier today where someone said (to a similar thread I found on ESD events) that since only the chassis was touched, it was likely nothing internal was impacted / damaged by the ESD event.

In any case, I will be far more careful going forward.
Also bought an outlet tester earlier today (not expensive, but very highly rated) just to check the outlets out easily to rule any outlet issues out.

Thanks again for the very helpful and reassuring feedback!

 

[njweb]

That can certainly happen. The static that builds up on your body in the winter on a nylon carpet, is thousands of volts. When discharged through delicate electronics, it can do permanent severe damage.

There is nothing wrong with your house wiring. But you got a warning to be very careful. You are lucky your receiver still works.

So I go the the expense of wool carpet in my AV room and not synthetics, and that helps a lot. I also have a central humidifier, and keep it to around 40%. That not only helps to prevent static, but is the sweet spot for discouraging the spread of infectious diseases.

Even so I try and remember to touch the grounded rack before any equipment. However, with this plan, so far I have had zero static events.

Thanks!
Yes, I felt very lucky not to have damaged it (keep in mind I had received it earlier yesterday and only had it hooked up for 2 hours when the ESD event occurred), trust me. I was really concerned that it would not power on or have other issues; thankfully my concern was short lived (when it powered right back on).

Many many years ago I blew both my speaker's tweeters (which I replaced myself easily for only $70 for the pair thankfully) when, while my receiver was turned on, I removed the 2 jumpers on my 'Pre Out / Main' jacks on my expensive stereo receiver (this was before surround sound even existed).

Ever since I have been careful and never blown anything; in fact, last night is the first time I even tripped a receiver (and I have owned many - close to 8 or 9 - over the years). I still own my last 2 surround sound receivers which I owned for a number of years (will sell one or both in the fall) and both still work fine - only upgraded each time to get support for the latest surround sound formats and latest technological enhancements.
Ironically, I always try to discharge myself by simply touching the metal foot of the AV stand my receiver is on, but I occasionally forget (like last night unfortunately)...

Smart moves with your carpet and central humidifier. I have nice Berber carpet and it is a large basement, so not going to redo it.
My house came with a central humidifier, so I can use it if needed. I will check the humidity level again (ironically I checked them a few weeks ago and they were in the upper 30's, close to 40% relative humidity, which was within the 30% - 40% range I had read about as being optimal (not for ESD, but for health reasons etc. I mean). Above 40% was considered "too humid" per the articles I read.

 

[lovinthehd]

Do not miss that static electricity stuff like when I lived in the midwest! I used to dig it somewhat as a kid, shuffling in your socks as much as possible and watching sparks fly onto a doorknob or something.....but don't think I ever killed anything electronic....

 

[M Code]

Today most AVRs are tested for ESD....
The ESD (electro static discharge) may be as high as 5KV but no current, however they will often push the unit to shutdown. This is very common in car audio electronics, that's why they will have a reset button..
Inside the CE product, memory and CPU chips don't like the ESD charge but today most CE products are designed to handle this without any issues just requires rebooting the product..

Just my $0.02....

 

[sterling shoote]

That can certainly happen. The static that builds up on your body in the winter on a nylon carpet, is thousands of volts. When discharged through delicate electronics, it can do permanent severe damage.

There is nothing wrong with your house wiring. But you got a warning to be very careful. You are lucky your receiver still works.

So I go the the expense of wool carpet in my AV room and not synthetics, and that helps a lot. I also have a central humidifier, and keep it to around 40%. That not only helps to prevent static, but is the sweet spot for discouraging the spread of infectious diseases.

Even so I try and remember to touch the grounded rack before any equipment. However, with this plan, so far I have had zero static events.

Yep, gotta have wool carpet.

 

[highfigh]

Just got home, so could not reply to thank you earlier.
Thanks a lot!

Regarding the "it depends on what you walked on": I walked on the Berber carpet (so definitely very conducive to static buildup occurring) in the basement; this, combined with the drier / dry winter air, contributed to the ESD event.
Agreed - If it starts to shut off every time, it may be too sensitive; or then again perhaps that is a great thing (it did not have a shutdown period and I was able to power it back on as soon as I pushed the power button.
In any case, the shutting off sensitivity being a bit too high (f that is the case) would not bother me, since I won't touch it often anyway (use the remote most of the time) and when I do touch it, I will try to never agai forget to discharge myself first - I usually touch the sturdy metal foot of the Sanus AV rack before touching my receiver).

Regarding your comment - "if it tripped instantly".... "being confident there is no permanent damage" - Thanks, that feedback gives me (extra) peace of mind!
Right, while 'instant' is a relative term since ESD can happen in nanoseconds (correct me if I am wrong all), it certainly tripped within a second of my touching it (and not later which would obviously be far more concerning), so I think that qualifies as "instant" in the sense you were referring to it.
And it did power up right away afterwards.

Finally, regarding this part - "The static voltage could have been quite high and would likely have caused damage if you were actually touching a part that is prone to such high voltage damage such as certain IC chips, or even FETs, but you only touched the chassis, that somehow got sensed by the protective circuit."
Thanks! Very useful information! I had read something quite similar earlier today where someone said (to a similar thread I found on ESD events) that since only the chassis was touched, it was likely nothing internal was impacted / damaged by the ESD event.

In any case, I will be far more careful going forward.
Also bought an outlet tester earlier today (not expensive, but very highly rated) just to check the outlets out easily to rule any outlet issues out.

Thanks again for the very helpful and reassuring feedback!

If the carpet was conductive, you wouldn't accumulate a static electrical charge- the whole reason it's called 'static' is because it doesn't go anywhere until you discharge it.

If you want to prevent this, you can do a few things-

1) buy a 1 Meg Ohm resistor and attach it to some part of the system that's grounded. If it means that you have to attach a wire to the screw on the wall plate for the outlet used for powering the system to provide the ground, do that. Touch the resistor's bare wire before touching any part of the system to discharge the electricity- it happens quickly, but you won't get a big shock and it will be far better for the equipment.

2) increase the humidity in your house.

There's nothing wrong with your electrical service- static electricity discharge means that whatever you touched is grounded. If you never get a shock, it means there's no path to ground.

 

[highfigh]

Do not miss that static electricity stuff like when I lived in the midwest! I used to dig it somewhat as a kid, shuffling in your socks as much as possible and watching sparks fly onto a doorknob or something.....but don't think I ever killed anything electronic....

When we were kids, there wasn't much that COULD have been killed by static electricity. Light bulbs, old TVs and motors? Nah.

I cut my finger just under the nail and when I touched something that was grounded, guess where the shock occurred- yup, right at the cut. Good times!

 

[highfigh]

That can certainly happen. The static that builds up on your body in the winter on a nylon carpet, is thousands of volts. When discharged through delicate electronics, it can do permanent severe damage.

There is nothing wrong with your house wiring. But you got a warning to be very careful. You are lucky your receiver still works.

So I go the the expense of wool carpet in my AV room and not synthetics, and that helps a lot. I also have a central humidifier, and keep it to around 40%. That not only helps to prevent static, but is the sweet spot for discouraging the spread of infectious diseases.

Even so I try and remember to touch the grounded rack before any equipment. However, with this plan, so far I have had zero static events.

My parents' house had wool loop pile carpeting- we used to shock the hell out of ourselves but it depends on what's on the feet- leather soled shoes aren't so bad, but synthetic soles or in socks, watch out!

Best practice- use a remote control or if the equipment has to be touched, add the resistor I mentioned in another post if the shocks are bad.

 

[njweb]

Today most AVRs are tested for ESD....
The ESD (electro static discharge) may be as high as 5KV but no current, however they will often push the unit to shutdown. This is very common in car audio electronics, that's why they will have a reset button..
Inside the CE product, memory and CPU chips don't like the ESD charge but today most CE products are designed to handle this without any issues just requires rebooting the product..

Just my $0.02....

Thanks a lot! That is reassuring.
Of course I will also do the following:
1) Continue to use the remote control as much as possible and not touch the receiver metal front panel or metal front panel door again.
2) Continue to touch the AV stand's metal leg before touching the receiver. I usually do this, but I neglected to do it Friday evening when the incident occurred.

3) Instead of point #2, or in addition to #2, I am also considering buying a 'CONDUCTIVE' antistatic mat to place in front of my AV stand and attaching the wire to the the screw in the middle of the double outlet plate behind my gear.

American Floor Mats

American Floor Mats brings you 25 years of floor mat experience. We are proud to offer you the most comprehensive selection of high quality door mats.

www.americanfloormats.com

But not entirely sure which type of ESD mat I need for my intended use (see link above which tries to explain the difference).
At first it seemed a 'conductive' antistatic mat was the right type (as opposed to 'static dissipative' antistatic mat)?
But re-thinking it through I am not sure now.

From the site:
Static Dissipative Mats and Conductive Mats are designed to protect sensitive equipment, such as computers and explosive chemicals, by quickly drawing the static electricity off workers before they touch such items. Humans quickly generate static electricity by walking, shifting their position or even rolling on a chair. Even the slightest touch can pass electricity onto sensitive equipment, which can destroy processors or cause flammable chemicals to ignite. In order to prevent such problems, we provide both Electrically Conductive and Static Dissipative mats. Conductive mats can disperse static electricity quicker than can static dissipative mats. Thus, conductive mats should be used near extra sensitive equipment. All conductive matting and dissipative matting needs to be grounded to function properly. For this, we provide ground cords, heel grounders and wrist straps.

 

[highfigh]

Thanks a lot! That is reassuring.
Of course I will also do the following:
1) Continue to use the remote control as much as possible and not touch the receiver metal front panel or metal front panel door again.
2) Continue to touch the AV stand's metal leg before touching the receiver. I usually do this, but I neglected to do it Friday evening when the incident occurred.

3) Instead of point #2, or in addition to #2, I am also considering buying a 'CONDUCTIVE' antistatic mat to place in front of my AV stand and attaching the wire to the the screw in the middle of the double outlet plate behind my gear.

American Floor Mats

American Floor Mats brings you 25 years of floor mat experience. We are proud to offer you the most comprehensive selection of high quality door mats.

www.americanfloormats.com

But not entirely sure which type of ESD mat I need for my intended use (see link above which tries to explain the difference).
At first it seemed a 'conductive' antistatic mat was the right type (as opposed to 'static dissipative' antistatic mat)?
But re-thinking it through I am not sure now.

From the site:
Static Dissipative Mats and Conductive Mats are designed to protect sensitive equipment, such as computers and explosive chemicals, by quickly drawing the static electricity off workers before they touch such items. Humans quickly generate static electricity by walking, shifting their position or even rolling on a chair. Even the slightest touch can pass electricity onto sensitive equipment, which can destroy processors or cause flammable chemicals to ignite. In order to prevent such problems, we provide both Electrically Conductive and Static Dissipative mats. Conductive mats can disperse static electricity quicker than can static dissipative mats. Thus, conductive mats should be used near extra sensitive equipment. All conductive matting and dissipative matting needs to be grounded to function properly. For this, we provide ground cords, heel grounders and wrist straps.

Or, you could keep it simple and use a resistor, like I do. I have never had an issue in over ten years and don't expect to.

 

[Pogre]

That can certainly happen. The static that builds up on your body in the winter on a nylon carpet, is thousands of volts. When discharged through delicate electronics, it can do permanent severe damage.

There is nothing wrong with your house wiring. But you got a warning to be very careful. You are lucky your receiver still works.

So I go the the expense of wool carpet in my AV room and not synthetics, and that helps a lot. I also have a central humidifier, and keep it to around 40%. That not only helps to prevent static, but is the sweet spot for discouraging the spread of infectious diseases.

Even so I try and remember to touch the grounded rack before any equipment. However, with this plan, so far I have had zero static events.

There you are! I hadn't seen any of your posts the last day or 2 and was hoping all is week with you. Good seeing you again doc!

I've never had a receiver do that but it doesn't sound like something that's TOO far outside of unusual. Now, my minidsp will do that sometimes when I dust. If I touch it and discharge a static shock it shuts off for a second then comes back on again. I do try to discharge on something else before touching my equipment when I dust.

 

[njweb]

Or, you could keep it simple and use a resistor, like I do. I have never had an issue in over ten years and don't expect to.

Thanks a lot!

I currently already use the technique of touching the metal feet of the AV stand to absorb the static electricity (I can hear / feel the discharge and it is not painful at all), so that works as well as the resistor approach IMHO.
Unfortunately forgot to do it Friday evening.

But both my method and the resistor method require me (or someone else) to remember to do so before touching the receiver.
Therefore I was thinking of the mat approach since there is no way to miss it, I would have to step on it before touching the receiver.
Hope that makes sense, thanks!

If I am missing something in the resistor technique, let me know.

Just not sure which mat would be the most appropriate.
Perhaps this one? But it does not explicitly say' conductive' in the item title...

American Floor Mats

American Floor Mats brings you 25 years of floor mat experience. We are proud to offer you the most comprehensive selection of high quality door mats.

www.americanfloormats.com

But they do not separate the
Static Dissipative Mats (ESD Mats)
from the
Conductive Mats

 

[njweb]

There you are! I hadn't seen any of your posts the last day or 2 and was hoping all is week with you. Good seeing you again doc!

I've never had a receiver do that but it doesn't sound like something that's TOO far outside of unusual. Now, my minidsp will do that sometimes when I dust. If I touch it and discharge a static shock it shuts off for a second then comes back on again. I do try to discharge on something else before touching my equipment when I dust.

I have also never had a receiver shut off before due to static discharge from my finger and I have had 7 or 8 of them, most of which had metal front panels.
As PENG suggested above, maybe the SR7013 (or mine specifically) has extra sensitive protection built into it.
It has been fine since the incident.
My last one (before the SR7013) had even more metal (the entire front panel was metal - on the SR7013, the left outer and right outer portion are plastic, including where the power button is).
That last receiver (which was in the same exact location as my new SR7013) never reacted to me when I touched the metal front panel, other than the tiny power standby button which was metal coated - only that button used to give me a very small static shock, but it never shut off from it. I have owned that receiver (Newcastle R-972 Trinnov receiver) for 8 years and it still works flawlessly.
It just does not support the latest surround formats, hence I got the SR7013...

 

[highfigh]

Thanks a lot!

I currently already use the technique of touching the metal feet of the AV stand to absorb the static electricity (I can hear / feel the discharge and it is not painful at all), so that works as well as the resistor approach IMHO.
Unfortunately forgot to do it Friday evening.

But both my method and the resistor method require me (or someone else) to remember to do so before touching the receiver.
Therefore I was thinking of the mat approach since there is no way to miss it, I would have to step on it before touching the receiver.
Hope that makes sense, thanks!

If I am missing something in the resistor technique, let me know.

Just not sure which mat would be the most appropriate.
Perhaps this one? But it does not explicitly say' conductive' in the item title...

American Floor Mats

American Floor Mats brings you 25 years of floor mat experience. We are proud to offer you the most comprehensive selection of high quality door mats.

www.americanfloormats.com

But they do not separate the
Static Dissipative Mats (ESD Mats)
from the
Conductive Mats

Your body is storing the energy- the mat will help, but you'll still be charged if it doesn't make the connection well, for some reason.

Make it visible- why spend a ton of money when you don't have to?

 

[njweb]

Your body is storing the energy- the mat will help, but you'll still be charged if it doesn't make the connection well, for some reason.

Make it visible- why spend a ton of money when you don't have to?

Understood that the mat may not be foolproof, depending also on how quickly one steps onto the mat and subsequently touches the receiver...

Been debating back and forth.
Well, the $62 + tax (-10% coupon) for the mat would be a protection plan of sorts and, to me, would be better than the hassle and downtime (as well as expense post warranty) of getting the receiver (or other gear) repaired since i may not be so lucky next time I touch it, or someone else touches it for that matter.

Luckily, I mostly use the remote and plan on keeping the door closed from now on; plus for the few times I may need to touch the receiver, I will now make an even more concerted effort (than I did before even) to touch the metal feet of my AV stand first.
It's discontinued, just sharing the photo to illustrate where the metal legs are.

Cutting Edge AV Products

The SANUS brand manufactures sleek, high-quality mounts, AV furniture, speaker stands, AV racks and accessories. Our products are engineered for top-of-the-line performance and tested to the highest safety standards.

www.sanus.com

Other methods require me, or anyone else who comes near it, to discharge themselves.
The mat is equally to prevent issues with other people touching it (I can see a family member or guest innocently touching it).
In my case it will remind me to discharge myself which I will do anyway.
My only concern is how the mat would look since they only have a dark pewter color and my carpet is much lighter.

Anyway, let me think about it. Thanks for the resistor suggestion as well.
I appreciate all the feedback from everyone. Great forum!

 

[njweb]

PS:
I would love to know, with some level of certainty, whether or not touching the front metal panel or front metal door, as a location, limits any electrical pulse's path /surge's path to just the chassis (as opposed to traveling to the internals (internal components such as circuitry and internal wiring etc.) of the receiver (directly or indirectly).
I guess an engineer or Marantz tech might have a good idea.
I thought I read something about this on a forum / online, but not sure.

I mean this as opposed to touching a metal connection at the back (speaker or HDMI input connection e.g.) which in turn directly connects to the internals (circuit boards, chips, wiring etc.); then you can almost guarantee the ESD event's pulse / surge will also travel to the connected internal components of the receiver.

 

[PENG]

PS:
I would love to know, with some level of certainty, whether or not touching the front metal panel or front metal door, as a location, limits any electrical pulse's path /surge's path to just the chassis (as opposed to traveling to the internals (internal components such as circuitry and internal wiring etc.) of the receiver (directly or indirectly).
I guess an engineer or Marantz tech might have a good idea.
I thought I read something about this on a forum / online, but not sure.

I mean this as opposed to touching a metal connection at the back (speaker or HDMI input connection e.g.) which in turn directly connects to the internals (circuit boards, chips, wiring etc.); then you can almost guarantee the ESD event's pulse / surge will also travel to the connected internal components of the receiver.

No need to be a Marantz engineer to say "yes". That would obviously be the direct path, but there would be other paths via capacitive coupling, that's likely why it triggered the protection.