Earth connection in Rotel components

[pbarata]

Why Rotel components like RSP-1066/68/98, RCD-1070/72 and RMB-1075 don't have the earth connector on power cords/back socket?

Compared to other manufacturers, like Arcam, NAD, all of them use earth connection in their designs. Is there any advantages doing so?

[Marlboroman]

Yes, I Think So.

[csuzor]

I have added an earth connection to my 1068. Without it (before, or if I forget to connect it), I always get electric shocks when I touch it or other components. Now, no more shocks from either 1068 or 1075. My 1075 doesnt have an earth, but it benefits from the earth connection on the 1068. It also reduced noise, but did not completely stop transformer hum, which depends on other factors (like the time of the day!) (I have heard that transformer hum is caused by DC voltage on the AC line, but have not bought special equipment to try to reduce it).

If you have another component with an earth connection (like RB-1080), then no need for 2 earth connections, excess charge will travel from other components through the analog connections to the earth.

[bigburner]

Why Rotel components like RSP-1066/68/98, RCD-1070/72 and RMB-1075 don't have the earth connector on power cords/back socket?

A piece of equipment with no earth pin is internally insulated from the external case to provide protection without the third wire.

[csuzor]

A piece of equipment with no earth pin is internally insulated from the external case to provide protection without the third wire.

Interesting, and that's theory. Why does the 1068 have such aweful electric discharge without the earth connection, and when I connect the external chassis to the earth there is no more discharge? Why does this same external chassis earth connection, remove electric discharge from the 1075 as well? I suspect there is a leak of current within the 1068 to the chassis. My kids were getting zapped quite strongly, it wasn't safe.


Let me add another experience: My computer and all the gear connected to it, was giving nasty electric discharges as well, but it did have an earth connection... It took me 3 years to unfold the mistery: The earth wire to that room was not connected to the earth in the household power distribution unit. When I did make the connection, no more electric discharge. If I now remove the earth pin on the PC, electric discharge occurs again.

[bigburner]

I suspect there is a leak of current within the 1068 to the chassis. My kids were getting zapped quite strongly, it wasn't safe.

Well that explains why you added an earth connection to your 1068!

Surely it must be a fault with your unit? It's hard to believe that there's a design fault in the 1068 that makes it unsafe. Imagine the law suit in America if just one unlucky punter got zapped.

Presumably most Western countries have a regulatory authority that verifies the safety of electrical equipment before it hits the shelves? New Zealand certainly does, and even Australia is probably thinking about it.

[csuzor]

There are several other owners of 1068 on this site with the static discharge problem... and those owners of 1068 but with an earthed amp (eg. 1080) won't notice it... No, I don't believe it's an isolated fault, more a design fault. Intentionally designing the preamp without an earth connection, to avoid potential extra "earth related noise", was not wise... maybe those engineers use the earthed amps, so they don't get zapped?

I'd like a Rotel official response on this. Please.

[pbarata]

There are several other owners of 1068 on this site with the static discharge problem... and those owners of 1068 but with an earthed amp (eg. 1080) won't notice it... No, I don't believe it's an isolated fault, more a design fault. Intentionally designing the preamp without an earth connection, to avoid potential extra "earth related noise", was not wise... maybe those engineers use the earthed amps, so they don't get zapped?

I'd like a Rotel official response on this. Please.

Speaking of danger, I think that with the RMB-1075/95 we could get really zapped from the face of the earth, if such a problem occurs.
:M

[miner]

Please explain Earth Connection to a novice.

[csuzor]

Earth connection add-on: I bought a do-it-yourself power plug, and connected a single wire to the earth pin. I connected a round lug on the other end of the wire, removed a screw from the body of the 1068, and replaced the screw including the lug.

This effectively connects the body of the 1068 to the household earth. If any loose wire inside the 1068 touches the body (or any other component such as 1075 or CD player or whatever), the current would immediately go the earth, and this would trip the household earth leakage protection, and shut off power everywhere. If I dont have this connection, I get tiny electric shocks every time I touch the unit, I am tough but my kids aren't. If there was a serious fault, and a wire inside the 1068 (or other component) touches the body of that component, that charge would be waiting for someone to touch it, and could kill.

imo, it is irresponsible to remove the earth connection from such components. Sure, internal insulation from the external case, as bigburner comments, is the minimum requirement... but not enough safety for me, and insufficient / faulty in the case of my 1068 (and others).

[Marcel B]

As far as I know static discharge is uncomfortable, but not dangerous.
Of course grounded equipment needs to be used with a grounded outlet but that's not for static electricity

Marcel B