 tschmidtPremium,MVM
join:2000-11-12
Milford, NH
kudos:5
 ·Fairpoint Commun..
 ·Hollis Hosting
| reply to skuv
Re: Bureaucracy or safety? said by skuv :
Doesn't everyone know that the FIOS ONT's have coax in them?
Why do people keep thinking the whole thing is fiber?
The main safety issue is whether or not copper exits the building. FYI, internally the ONT has more then just coax interface, it also has twisted pair for Ethernet and voice.
If you hook up a rabbit ear indoor antenna it does not need to be grounded just because it uses coax. The purpose of grounding/bonding is protection from foreign induced voltage. Wiring that exits the building is vulnerable to this either from lightning or power crosses. I agree with cdru  that most consumer AV equipment is two-wire rather then three-wire (safety ground) as such it is likely there will be some leakage to coax shield. However if leakage current results in dangerous levels of voltage on the coax bonding ONT reduces but does not eliminate danger since disconnecting coax from ONT also removes ground.
If what cdru posted is correct that ONT power supply uses a two wire plug then the only source of safety ground is bonding ONT to residential ground system.
Regardless - having a high quality ground improves safety, often reduces susceptible to RF interference, and is best practice.
/tom |
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 cdruGo ColtsPremium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:5
 ·Frontier FiOS
| said by tschmidt:If what cdru posted is correct that ONT power supply uses a two wire plug then the only source of safety ground is bonding ONT to residential ground system. I was mistaken. It was flat, but was a 3-conductor cord. However, that was only to the power supply. To the battery pack, it was just a 2-wire connection. |
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tschmidtPremium,MVM
join:2000-11-12
Milford, NH
kudos:5 Reviews:
·Fairpoint Commun..
·Hollis Hosting
| said by cdru: To the battery pack, it was just a 2-wire connection. In other posts in this thread it appears some of the early ONTs did use two wire AC plug.
With two wire DC supply that begs the question: is DC supply safety ground referenced or floating?
If I had to venture a guess I'd say it was ground referenced. If this was the computer industry mostly likely negative rail would be connected to safety ground. Being a Telcom ONT that may not be the case as phone companies like -48 volts.
/tom |
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