TiVo Community
TiVo Community
TiVo Community
Go Back   TiVo Community > Main TiVo Forums > TiVo Roamio DVRs
TiVo Community
Reply
Forum Jump
 
Thread Tools Rate Thread
Old 01-16-2014, 02:06 PM   #91
jmpage2
Registered User
 
jmpage2's Avatar
 
Join Date: Jan 2004
Posts: 1,888
Quote:
Originally Posted by tarheelblue32 View Post
Well, better than nothing might have to do. I am open to other suggestions, but as the APC one is no longer manufactured and you appear to have cleaned out the stock on ebay, it won't be easy to find.

It will probably be fine. It looks like the APC one is available in a modular version.

http://www.apc.com/products/resource...m?base_sku=PVR

You would probably have to buy the four slot rack for it as well. Your other device seems more economically practical.
jmpage2 is offline   Reply With Quote
Old 01-16-2014, 02:13 PM   #92
tarheelblue32
Registered User
 
tarheelblue32's Avatar
 
Join Date: Jan 2014
Location: Raleigh, NC
Posts: 1,164
Quote:
Originally Posted by jmpage2 View Post
It will probably be fine. It looks like the APC one is available in a modular version.

http://www.apc.com/products/resource...m?base_sku=PVR

You would probably have to buy the four slot rack for it as well. Your other device seems more economically practical.

Yeah I think I'll just go with the Tii point-of-entry surge suppressor. I also have a grounded drop amp that supposedly has some surge suppression to it and I have the coax going to my Roamio going through the coax port on a surge protector power strip. Hopefully all that together will be enough to stop most surges from causing damage. I doubt there is anything on the market that is economically practical that can actually stop a direct lightning strike anyways.
tarheelblue32 is offline   Reply With Quote
Old 01-16-2014, 04:11 PM   #93
jmpage2
Registered User
 
jmpage2's Avatar
 
Join Date: Jan 2004
Posts: 1,888
Quote:
Originally Posted by tarheelblue32 View Post
Yeah I think I'll just go with the Tii point-of-entry surge suppressor. I also have a grounded drop amp that supposedly has some surge suppression to it and I have the coax going to my Roamio going through the coax port on a surge protector power strip. Hopefully all that together will be enough to stop most surges from causing damage. I doubt there is anything on the market that is economically practical that can actually stop a direct lightning strike anyways.
Direct lightning strikes on homes are uncommon. Where lightning is common, homes at higher elevations often have lightning rods to at least minimize the damage.

Believe it or not, but a high enough quality surge suppressor that also incorporates a fast fuse can actually sacrifice itself in order to save the connected equipment even in cases of "direct strike".

Nearly all surge damage from strikes is when the lightning hits close to the home location and travels through ground wiring, etc, to enter into the home.

Last edited by jmpage2 : 01-16-2014 at 04:34 PM.
jmpage2 is offline   Reply With Quote
Old 01-16-2014, 06:11 PM   #94
shrike4242
Registered User
 
Join Date: Nov 2006
Location: Saint Louis, MO
Posts: 276
Quote:
Originally Posted by jmpage2 View Post
Direct lightning strikes on homes are uncommon. Where lightning is common, homes at higher elevations often have lightning rods to at least minimize the damage.

Believe it or not, but a high enough quality surge suppressor that also incorporates a fast fuse can actually sacrifice itself in order to save the connected equipment even in cases of "direct strike".

Nearly all surge damage from strikes is when the lightning hits close to the home location and travels through ground wiring, etc, to enter into the home.
So, would the only thing needed be one at the cable POE between the entry feed and any splitters/etc from that entry feed?
shrike4242 is offline   Reply With Quote
Old 01-16-2014, 08:29 PM   #95
jmpage2
Registered User
 
jmpage2's Avatar
 
Join Date: Jan 2004
Posts: 1,888
Quote:
Originally Posted by shrike4242 View Post
So, would the only thing needed be one at the cable POE between the entry feed and any splitters/etc from that entry feed?
There is only a need for one at the point of entry. You don't need them anywhere else because surges should only enter over coax from outside of the home, unless you don't have adequate electrical surge suppression on your coax connected electronics which can then back feed over the coax network if they get zapped.
jmpage2 is offline   Reply With Quote
Old 01-16-2014, 11:58 PM   #96
westom
Registered User
 
Join Date: Jan 2010
Posts: 83
Quote:
Originally Posted by shrike4242 View Post
So, would the only thing needed be one at the cable POE between the entry feed and any splitters/etc from that entry feed?
Assumed is that a protector works by blocking or absorbing a surge. Protectors that do that are for surges too tiny to damage appliances. Recommendations based in hearsay are easily separated from other recommendations based in science. Destructive surges can be hundreds of thousands of joules. How does any protector absorb that energy? Where is a number for how much energy it will absorb? That number even demonstrates why one device called a protector does virtually no protection. And a completely different device called a protector harmlessly earths hundreds of thousands of joules.

Learn how a protector and protection work. Two completely different components of a surge protection 'system'. Many discuss the item called a protector and completely ignore another more important item called protection. These concepts were originally introduced in elementary school science.

A surge current seeks earth ground. One conductive path to earth was a wooden church steeple. But wood was not conductive enough; creates a high voltage. A 10,000 amps surge current times a resulting high voltage means high energy dissipated destructively in a steeple.

How did Franklin avert damage? He simply diverted lightning to earth on a path that creates a near zero voltage. Then 10,000 amps times a resulting near zero voltage is near zero energy. No damage. Then hundreds of thousands of joules dissipate harmlessly in earth.

Will a power strip protector stop what three miles of sky could not? Of course not. Will its few hundred joules absorb those hundreds of thousands of joules that three miles of sky could not absorb? Of course not. Many make claims by ignoring spec numbers and what was even demonstrated by Franklin.

One 'whole house' protector means 10,000 amps creates a near zero voltage. Just like a lightning rod. But only if connected low impedance (ie 'less than 10 feet') to what actually does the protection - earth ground. Neither lightning rod nor protector do protection. Those are only connecting devices. Protection is always defined by what absorbs hundreds of thousands of joules - earth ground.

Potentially destructive surges occur maybe once every seven years. Facilities that cannot have damage always upgrade earthing to make a 'whole house' protector effective. So that protection already inside every appliance is not overwhelmed.

Numbers that define it. A lightning strike is maybe 20,000 amps. So an effective protector connects at least 50,000 amps low impedance to earth. This superior solution also costs less money; about $1 per protected appliance.

Is a device between entry point and splitter connected low impedance (ie 'less than 10 foot') to single point earth ground? If not, then it does not claim and will not discuss numbers that define effective protection. Protection about a connection to what harmlessly absorbs energy. Useful recommendations always discuss that well proven science.

Last edited by westom : 01-17-2014 at 12:07 AM.
westom is offline   Reply With Quote
Old 01-17-2014, 05:03 PM   #97
bud--
Registered User
 
Join Date: Jan 2014
Posts: 1
Excellent information on surges and surge protection is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
- "How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits" published by the IEEE (the IEEE is a major organization of electrical and electronic engineers).
And also:
http://www.eeel.nist.gov/817/pubs/sp...%20happen!.pdf
- "NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home" published by the US National Institute of Standards and Technology

The IEEE surge guide is aimed at people with some technical background.

Quote:
Originally Posted by westom View Post
Assumed is that a protector works by blocking or absorbing a surge.
Neither plug-in or service panel surge protectors work by "blocking" or "absorbing" surges.

Quote:
Originally Posted by westom View Post
Destructive surges can be hundreds of thousands of joules. How does any protector absorb that energy?
They don't.

An investigation by the author of the NIST surge guide looked at the amount of energy that could be absorbed at a plug-in protector. Branch circuits were 10m and longer, and surges coming in on power wires were up to 10,000A (which is the maximum probable surge, as below). The maximum energy was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. Plug-in protectors with much higher ratings are readily available.

(Protectors do not protect by absorbing the surge energy, but they absorb some energy in the process of protecting.)

Quote:
Originally Posted by westom View Post
Will a power strip protector stop what three miles of sky could not? Of course not.
Of course not.
Plug-in protectors do not work by "stopping".

But both the IEEE and NIST surge guides say plug-in protectors are effective. The only 2 detailed examples of protection in the IEEE surge guide use plug-in protectors.

If using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like coax also must go through the protector. As explained in the IEEE surge guide (starting page 30) plug-in protectors work primarily by limiting the voltage from each wire to the ground at the protector. To do that all wires must go through the protector.

Quote:
Originally Posted by westom View Post
One 'whole house' protector means 10,000 amps creates a near zero voltage.
Service panel protectors are a real good idea.
But from the NIST surge guide:
"Q - Will a surge protector installed at the service entrance be sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances [electronic equipment], No for two-link appliances [equipment connected to power AND cable or phone or....]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO - but that does not mean that a surge protector installed at the service entrance is useless."

Service panel protectors do not, by themselves, prevent high voltages from developing between power and cable/phone wires. The NIST surge guide suggests most equipment damage is from high voltage between power and signal wires. An example of where a service panel protector would provide no protection is the IEEE surge guide example starting page 30.

But service panel protectors are very likely to protect anything connected only to power wires from a very near very strong lightning strike.

If you have a service panel protector AND if you have an effective cable protector at the point of entry AND there is a short ground wire from both the panel and cable protector to a common connection point, then devices in the house that connect to both cable and power are likely safe.

Gas discharge tubes in a cable protector have a short time delay as the gas ionizes.

During a surge 'event' the wiring in the house may rise far above 'absolute' ground potential. Much of the protection is that all wiring rises together.

Quote:
Originally Posted by westom View Post
Numbers that define it. A lightning strike is maybe 20,000 amps. So an effective protector connects at least 50,000 amps low impedance to earth.
An "average" lightning strike is about 20,000A. But that is not the surge current to a house that is caused by the strike (unless lightning hits the house, which requires lighting rods for protection).

The author of the NIST surge guide looked at the surge current that could come in on residential power wires. The maximum with any reasonable probability of occurring was 10,000A per wire. That is based on a 100,000A lighting strike to a utility pole adjacent to the house in typical urban overhead distribution.

Recommended ratings for service panel protectors is in the IEEE surge guide on page 18. Ratings far higher than 10,000A per wire mean the protector will have a long life.
bud-- is offline   Reply With Quote
Old 01-18-2014, 12:26 PM   #98
aaronwt
HD Addict
 
aaronwt's Avatar
 
Join Date: Jan 2002
Location: Northern VA(Woodbridge)
Posts: 13,848
I just got the three year extended warranty from TiVo on my Roamio Basic I got from them in November. For only $40 it's not a bad deal. My Roamio Pro has a four year extended warranty from BestBuy. But that cost $70.

Although my Roamio Basic is not on lifetime service like my Roamio Pro is. My Roamio BAsic is on the $6.95 a month plan. But at that rate it takes 57 months to hit the break even point when compared with MSD $400 lifetime service.
__________________
Roamio Pro
TiVo Mini x4
Roamio Basic OTA
39TB unRAID1--53TB unRAID2--36TB unRAID3
XBL/PSN: WormholeXtreme
aaronwt is offline   Reply With Quote
Reply
Forum Jump




Thread Tools
Rate This Thread
Rate This Thread:


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Advertisements

TiVo Community
Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
vBulletin Skins by: Relivo Media

(C) 2013 Magenium Solutions - All Rights Reserved. No information may be posted elsewhere without written permission.
TiVoŽ is a registered trademark of TiVo Inc. This site is not owned or operated by TiVo Inc.
All times are GMT -5. The time now is 11:06 PM.
OUR NETWORK: MyOpenRouter | TechLore | SansaCommunity | RoboCommunity | MediaSmart Home | Explore3DTV | Dijit Community | DVR Playground |