Re: electrical / surge question

[w_tom <w_tom1@xxxxxxxxxxx>]

  Jack Painter, Richard Harrison, and other industry
professional discuss the most critical aspect of protection in
the newsgroup rec.radio.amateur.antenna  entitled "House
ground rod question" starting 22 April 2005 .  Protection is
not the protector.  Protection is earthing.  The protector
will only be as effective as its earthing.

  If all wires entering your building were earthed, then
destructive transients could not harm your RC80.  But then no
utility services are provided.  We must both earth those
utility wires AND have utility service.  So we install a
protector to earth those wires only during transients.

  Wires that enter your appliances that are no different from
antennas, which is why that other discussion is relevant.   We
install a protector to earth each wire only during the
transient.  No effective protector will stop, block, or absorb
transients as urban myths so often will claim.  If your
Leviton 51120 did not earth a destructive transient, then the
Leviton 51120 may not be properly connected to earth.  Again,
earthing is also discussed in "House ground rod question".

  If your earthing is compromised - disconnected, too long,
wire has splices or sharp bends or is bundled with other
wires, not using a single point ground, etc; then you would
not have effective earthing.

   Electricians understand installations to protect humans -
as required by code.  But electricians may not understand
additional requirements to protect transistors.  There are no
code requirements for transistor protection.

  All utilities must first make a 'less than 10 foot'
connection to a single point earth ground where utilities
enter the building.  All utilities must enter at the same
location.  The Leviton 51120 can only earth each utility wire
if the 51120 is properly earthed.  That earthing connection
must be short (less than 10 foot), direct (no splices, no
sharp bends), and independent (must not be shared with any
other ground until all grounds meet at the same ground
electrode  AND  must not be bundled with any other
non-grounding wires).  If these principles are violated, then
the Leviton 51120 may not provide the protection (the
earthing) that  RC80 transistor protection requires.

  When a protector does not provide protection, well, the
first thing to suspect is the quality of and connections to
protection.  To be effective, that protector must connected to
protection.  Protection is the single point earth ground - ie
that ground rod.  A protector is only as effective as that
earth ground.

ssg4605 wrote:
> Here is my basic setup:
>
> HAI Omni LT w/ 2 RC80's and an outdoor temp sensor.
>
> I also have a Leviton 51120-PTC Multimedia Surge Suppression Panel installed.
>
> Last night I we had a lighting storm.  The power went off once for
> about a second. Now one of my RC80's appears to be dead.  I took
> the second RC80 and installed it in the first location and
> verified that it is not the wiring.  When the bad RC80 is plugged
> in the Omni reports the heating/cooling setpoints correctly, but
> the temp is set to '0'.  The installer guide tells me when the
> temp sensor is broken, the tstat will appear dead, so I am
> assuming this is what got fried.
>
> My first question:  Did the lighting/power surge/something
> electrical destroy my tstat, even with the 51120-PTC?
>
> My second question:  I know absolutely nothing about electricity.
> Is there any chance the 51120-PTC is installed incorrectly?  The
> reason I ask is that there are 2 circuit breakers on my panel
> that are labeled "Surge Surpressor".  My understanding was that
> the surpressor would sit between the incoming electricity and the
> house.  Is that the case?  Could the surpressor just be
> protecting certain areas of the house?
>
> thank you so much for your help.  I have been following these forums
> for a while and I  really respect your opinions.
>
> steve