[TowerTalk] grounding

[Mahlon Haunschild]

"Neutral" is also bonded to the power distribution neutral feeder and a 
ground rod/wire of some sort at each service pole, so it's probably more 
difficult for the transformer secondary neutral to float than it appears.

regards,

Mahlon - K4OQ

Eric Scace K3NA wrote:

>    Pardon me, but I'm a little slow at this.
> 
>    Isn't it true that, at the pole/pad transformer, your house's neutral is derived from the transformer's center tap and tied to
> earth ground?
> 
>    If that is correct, then is it a correct understanding of your message that you are concerned about a surge on the electric
> utility's earth conductor which is not fully earthed at the transformer neutral... and continues on to your local ground?
> 
>    And if that is a correct understanding, then wouldn't the induced current on the other lines be a common mode current?  In that
> case all four lines (ground, neutral, +120 and -120) rise together, so the differential voltages between neutral and +120/-120
> should be rather small?  Wouldn't the surge protector at the common point of entry into the house divert this to the excellent local
> earth ground at the single point of entrance?  (Isn't that what the surge protector is for?)
> 
> -- Eric K3NA
> 
> -----Original Message-----
> From: towertalk-bounces at contesting.com
> [mailto:towertalk-bounces at contesting.com]On Behalf Of Glenn Noska
> Sent: 2004 January 19 20:45
> To: towertalk at contesting.com
> Cc: nazgul34 at hotmail.com
> Subject: [TowerTalk] grounding
> 
> 
>      i'm an electrician in the surge capital of the world, Orlando ( did
> lightning just hit that house?), Florida. the last three days were spent
> devouring old towertalk threads on grounding, super informative! well, surge
> protectors are pretty useless without a good ground and armed with towertalk
> knowledge i was ready to give my customer's the best ground their money
> could buy.
>      then, a really sharp engineer at Intermatic dropped this little
> bombshell. if your ground is a lot better than the utility's ground at the
> transformer then all the neighborhood's surges are coming for a visit. and
> you might think they're just coming to your ground, but, as they travel the
> common they induce surges in the two hots. So, you may have dodged the big
> surge, and bought yourself a whole lot of little ones.
>       is this significant? do i need to put a big horkin MOV on the neutral
> to the meter that'll add a couple dozen ohms and keep the neighborhood's
> surges out? is there such a thing?
>      all kidding aside, i'm guaranteeing all appliances and electronics to
> $10,000.00 or the homeowner's deductable (installing Intermatic
> IG1300-4T-2C). please help.