Grounding the receiver

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yeshu26

Regular Member
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My Pace receiver is made in Eastern Europe, and it does not have an earth connection. Only phase and neutral plug.

1. Do satellite receivers must be grounded? Why not, and why yes?

2. Many times I have to "cold start" the receiver when some weak channels on Sirius disappear, thats when I can hear a BOOM from the TV speakers. Is it cause there is some residual charge in the receiver which has not grounded properly?

cheers
 
yeshu26 said:
My Pace receiver is made in Eastern Europe, and it does not have an earth connection. Only phase and neutral plug.

1. Do satellite receivers must be grounded? Why not, and why yes?

2. Many times I have to "cold start" the receiver when some weak channels on Sirius disappear, thats when I can hear a BOOM from the TV speakers. Is it cause there is some residual charge in the receiver which has not grounded properly?

cheers
Click to expand...

I've yet to come across a consumer receiver that has been earthed.
If you really want, you can connect a ground wire to the chassis. (NOT the ground wire from the wall outlet thought!)
But that's not advisable unless you know what you're doing.
Most cases, it'll make no difference as the device is designed to work without grounding.
The pop's you may hear are either analog surges (bad electronic design), or digital non-zero-crossing buffer fills.
I don't think the origin of your receiver in principle has any effect on the popping noise in your speakers.

Only thing I can think of is try to common-ground (i.e. connect the chassis's) of your STB and TV (BUT NOT TO THE WALL OUTLET!)
This is (partially) how pro-audio stuff works; the important thing is to have a common ground as reference for voltage differences. If you use the power ground, you may have hum induction etc. Easier to deign consumer stuff to be isolated from the power circuits and their ground.
 
It's a Class 2 (Double Insulated) Appliance that does not require an earth connection.

Indeed, you should not provide one

Here's the simplest explanation I could find _http://www.double-insulated.com/
 
What will happen if I ground it?

Me and my family, have got static shock from the receiver, and the coaxial cable 100's of time from it, especially during rains.



Tivù said:
It's a Class 2 (Double Insulated) Appliance that does not require an earth connection.

Indeed, you should not provide one

Here's the simplest explanation I could find _http://www.double-insulated.com/
Click to expand...
 
I suggest you read Internet Resources as protection against indirect contact and against direct contact is a fairly in depth matter more in the domain of electrical engineers and sparkies.

But, basically, the design is such that the case (even though it is metal) cannot become live at mains voltage even under fault conditions.

ie The case is isolated from the mains - so if you then attach a conductor (earth wire) from the case to the house wiring, you increase danger during fault conditions by creating the capacity for direct contact with mains voltage during fault conditions until such time as any protective device operates.


For the avoidance of doubt, the shocks you get are from circulating currents (not "static") and are not dangerous.
 
In your first post, you say the receiver is Eastern European. Is it therefore fitted with a two pin continental plug which you probably have running into the mains via a two pin to three pin (UK) adaptor? It's possible that you have the two pin plug 'reversed' with the live going to neutral and neutral going to live. (A situation which often occurs with double insulated appliances here in France) It shouldn't make any difference, however if the receiver is fitted with a mains lead that plugs into the rear of the receiver you could buy a replacement fitted with a UK 13A mains plug.
 
Yes, that is why I was thinking of running the walls ground into the chasis of the receiver.

sonnetpete said:
In your first post, you say the receiver is Eastern European. Is it therefore fitted with a two pin continental plug which you probably have running into the mains via a two pin to three pin (UK) adaptor? It's possible that you have the two pin plug 'reversed' with the live going to neutral and neutral going to live. (A situation which often occurs with double insulated appliances here in France) It shouldn't make any difference, however if the receiver is fitted with a mains lead that plugs into the rear of the receiver you could buy a replacement fitted with a UK 13A mains plug.
Click to expand...
 
No - you MUST NOT provide a connection fron the case to any part of the house's electrical system.

You destroy the designed protective measure (double insulation) and increase the risk of contact with dangerous voltages under fault conditions.
 
You've misunderstood what I wrote and I must also reinforce what Tivù has written. Do not attempt on any account to run an earth to the chassis of the receiver. My suggestion to exchange the mains lead for a UK one was only to ensure that the phasing of the live and neutral would be correct.
 
Precisely - By all means fit a BS1363 plug, but with only the L/N pins connected.
 
Tivù said:
It's a Class 2 (Double Insulated) Appliance that does not require an earth connection.
Click to expand...
I don't really understand this (and I'm a qualified electrician). Class II was always things like a Bosch drill with an outer case made of insulating material. With a Pace receiver the chassis (and rear 'F' connector) are conductors. So if something drops out (like a screw, or a wire) and bridges between the the 240v and the case the case will go live. How can that be considered double insulated? What am I missing?

And to be honest, after fiddling about with these boxes for several years I've had a few nasty belts off them and the aerial cable braid that have made me let go in a hurry.
 
sonnetpete said:
You've misunderstood what I wrote and I must also reinforce what Tivù has written. Do not attempt on any account to run an earth to the chassis of the receiver. My suggestion to exchange the mains lead for a UK one was only to ensure that the phasing of the live and neutral would be correct.
Click to expand...
Colour coding will usually make absolutely no difference if the mains lead is detachable from the receiver and fits into a figure of eight socket on the receiver - which is definitely not keyed to ensure connecting the right way round. Why they bother colour coding the wires on that sort of connector is beyond me.
 
Huevos: Without going into really rather a lot of detail about the design and protection concepts that is already freely available (so you can read at leisure), being a qualfied electrician doesn't mean familiarity with all standards, concepts, means of protection etc. - I'm a Fellow of the IET (Formerly IEE), Chartered Engineer and former Principal Electrical Specialist with our HSE. I've sat on BS/EN committees, contributed to Technical Guidance and Legal Instruments, carried out Investigations, Prosecutions etc, performed Trade Assessments on UK Sparkies - but I never ever did (or do now, even though I no longer practice) presume to know everything: Lots of updating, research etc. was always the order of the day. Big, big subject area!

But the fact remains that virtually all modern electronic devices are Double Insulated and require CE Marking to demonstrate compliance with all relevant EC Directives and Regulations. There are rogues - always have been and always will be - and the mere fixing of a Compliance Mark on its own is not good enough for someone with a deeper interest (Like I had when working) as one would often have to resort to asking for the Technical File allegedly supporting the addition of a CE Mark.



As for the unpleasant tingles, I suspect we all get those!



Edit: PS I have never examined in detail the precise design of the box in question nor consulted its Technical File, so how it complies I cannot say: But it claims to and that is what (In our Consumer hats) we rely upon unless given cause to think otherwise.
 
Yes, it's a very valid point that you can turn over the figure of eight plug, reversing the phase. I don't think it would happen too often but of course you should ensure you have it inserted correctly in the first place. Perhaps the days of applying a mains testing neon to an exposed part of the metal chassis and seeing if it glows are long gone.

I've also had my fair share of unpleasant tingles, thankfully nowadays they only occurr if I go to sleep resting on my arm.

The point still remains that the OP shouldn't run an earth to the receiver chassis!
 
Tivù said:
Huevos: Without going into really rather a lot of detail about the design and protection concepts that is already freely available (so you can read at leisure), being a qualfied electrician doesn't mean familiarity with all standards, concepts, means of protection etc
Click to expand...
What I meant is I'm not completely green. What I am really asking is if something formed a bridge between the live feed and the case is the case going to go live, or is there some mechanism in play that handles that. I know these days most installs are RCD protected but it still seems a bit dodgy to me having an exposed metal chassis.
 
Well you could refer to IEC 61140 which is the generic Standard (among many that were spawned by the venerable IEC1010) applicable to the common aspects of protection against electric shock for equipment.

There are many related and more specific standards up in the IEC 61xxx series which home in on groups of equipment for certain purposes.

Frankly, I cannot bring to mind the child Standard for Domestic Equipment up to 600v, but if you want to fully assuage your interest I'm sure you'll be able to track it down - but 61140 should suffice.



BTW RCDs provide only secondary protection as they are not a preventive measure, but a reactive one. ie They do not prevent shock, but (if they work) limit the duration of exposure to dangerous voltages. Class 11/Double Insulation is a primary measure intended to prevent exposure to dangerous voltages in the first place.

I suspect that we're in danger of going too far off topic now! So, if consluting the Standard(s) doesn't satisfy, there are a great many electrical/electronic related Forums out there.
 
Interesting post. Indeed helped me to learn why some things have 2 pins, and others not.

Cheers Lads!
 
If you ground the coax coming into the house from the satellite dish (as all coax to an antenna should be) you will ground the case of the receiver, (if the case is made of metal) no additional ground is needed.
 
I have a belkin AV surge protector with provision for modems, TV aerial, and Satellite cable surge protection also.

When I checked the "continuity " with a multi meter between the "ground" of the satellite sockets, and the "ground of the surge protector's Earth pin of the plug, it showed a short!

That means all the ground points of satellite, and TV aerial sockets of the protection unit WILL BE GROUNDED to the house earth.

I remember someone saying on this thread, that it is a very bad idea to "earth" your LNB?

Did belkin's engineer's got it wrong?
 
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