# TiVo Series 1 Australian safety concerns



## Aussie (Jan 11, 2001)

Hi Folks

I'm could use some advice, ideally from somebody who is qualified to answer, but expert hobbyists are also welcome to contribute opinions.

As many of you know, there is an active community of TiVo users in Australia, and we love our TiVo's! They're totally unsupported by TiVo Inc here, but we've managed to achieve high level of functionality thanks to some truly brilliant linux hackers in our country! Starting from one TiVo in the year 2000 we've now got a self supporting community of over 1,000 Series 1 TiVos operating happily and without problems. (You probably know that if you have an ethernet card in a Series 1 TiVo you can thank the Australian TiVo Community for it!)

But suddenly a problem looms! A person, apparently an electrician, has posted a warning that our TiVos are unsafe to various Australian internet forums, you may see an example here and he has also claimed to have notified "the authorities." (Actually some of the responses to this thread are rather amusing, I think!)

He supplied more details of his concerns in another posting here but the nitty gritty of it (I'm no expert!) appears to boil down to the fact that earthing is provided via the antenna socket in the USA, but not in Australia. Here's a quote:



> "In the USA, STB's and computer TV, cable and satellite cards are earthed through the antenna connector via the shielded cable at the point of entry into the premises. The shielded cable and antenna are earthed to an earth electrode, mandatory wired to USA National Electrical Standards. A wiring diagram, list of components, USA National Electrical Standards clauses and safety warnings are included with the user manuals.
> 
> Therefore a three pin earthed mains connections plug and wall socket for STB's is not required. The mains connection made through the polarised two pin USA 110 volt mains plug is adequate and safe."


Can anybody offer any comments on this? If it's true then surely if the antenna is part of the earth path then not having an antenna plugged in would constitute a safety risk to you guys too, yet a TiVo can operate perfectly well without one?

Anybody want to offer any comments?

Cheers
Aussie


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## jafa (Jan 27, 2002)

Hi,

The TiVo uses a fully isolated power supply - there is no use or need to ground it.

Take a look at your video recorder... it is metal and it doesn't have a ground pin. It uses the same style of power supply.

The metal case and all electronic parts inside (excluding the input stage of the power supply) have no connection to mains electricity.

There are two saftey risks with a TiVo...
1) The the input stage of the power supply is exposed once you open the case - don't touch it!
2) The case has sharp metal edges - bleeding all over your tivo isn't good for it.

Nick


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## RonDawg (Jan 12, 2006)

Many relatively low-power electrical products in the USA only use a two-prong connection. Many of them are common appliances such as toaster ovens, mixers, can openers, fans, etc. which lack antenna connections, so I don't think that's the reason for the ability to get away with a lack of a grounding plug.

The safety of our appliances has to do with appliance design itself (I have some two-prong power tools that say "Double Insulated" on them) as well as the fact that we only operate at 110-120 volts, rather than the 220-240 volts common in the rest of the world. Our electrical outlets even lack the switches found on the higher-voltage counterparts; the only time you'll see an outlet with a built-in switch in the USA is one that's near a source of water (bathroom or kitchen counter), and it's only meant to test the internal "ground fault" circuitry to detect a circuit leak, rather than as an on/off switch.


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## Diana Collins (Aug 21, 2002)

From the above referenced post:


> ...The USA premises earthing standards are illegal and dangerous in Australia...


I had no idea that electricity worked differently in Australia than in the USA! 

A TiVo operating in Australia is no more, or less, dangerous than one operating in the US. I assume that coaxial leads entering a residence in Australia are earthed just as they are in the US. If not, lightning strikes on the attached antennas or distritbution junctions (which tend to be high off the ground) would introduce dangerous voltages and fire dangers into the residence.

The issue of multiple paths to earth is just as true here in the US. The National Electrical Code calls for all earths to unified (i.e. tied together) to avoid this problem.

So, this really boils down to two different questions:

1) The "safety" issue. This is no different in Australia than it is in the US. Some tight-arsed electrician's opinion notwithstanding.

2) The "legal" issue. This is quite real. If TiVos are imported into Australia without meeting the required governmental standards, the importer is liable for any damages arising from their use. The more significant concern is that an insurance company might deny a claim for fire damage if they discover an uncertified electrical device was in use, even if that device did not start the fire. In any event, this falls under the heading of "caveat emptor."


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