Upgrading House Electrical

[theoldwizard1]

About 10 years ago, the building I used to work in upgraded all of the "motor" circuit or circuits that had separate disconnects (all were 3 phase, various voltages).

To me AFCI make most sense on circuit where the load has a high start current (motors). My gut says, it is another way for electrical suppliers to make more money (like mandatory "childproof" receptacles).

 

[n8n]

You just brought up another good point. If you're using tamper resistant receps (required by code now) order them ahead of time... spec grade ones are not readily available in the retail market, and I don't like installing anything less.

Sent from my XT897 using Tapatalk

 

[bgeery]

Take a look at the Square D HEPD80 for your whole house surge suppressor. $85 on Amazon, 80,000 amp Surge Current Rating, 25,000 amp SCC. Indoor or outdoor install. 5 year warranty, $50K connected equipment warranty. Best rated for the capacity and money.

PS: Completely off topic, but as you are doing electrical safely improvements, include a few fire extinguishers throughout the house as wll. These things can stop a fire quick, and save you all the water damage the fire department would create. Might even qualify for an insurance discount.

 

[westom]

Take a look at the Square D HEPD80 for your whole house surge suppressor. $85 on Amazon, 80,000 amp Surge Current Rating, 25,000 amp SCC. Indoor or outdoor install. 5 year warranty, $50K connected equipment warranty. Best rated for the capacity and money.

No protector does protection. The 'whole house' protector is so superior due to a low impedance (ie 'less than 10 feet') connection to what actually does protection. Protection is about where hundreds of thousands of joules are harmlessly absorbed. That is single point earth ground. All four words have electrical significance. Also upgrade the earth ground to both meet and exceed code requirements.

For example, if a grounding hardwire goes up over the foundation and down to an electrode, then protection is compromised. Too many sharp bends. Hardwire too long (higher impedance). Hardwire adjacent to non-grounding wires. Best is a hardwire through the foundation and down to an upgraded earth ground.

A protector is only as effective as its earth ground.

Second, a protector must be sized so as to not fail even with direct lightning strikes. Lightning is typically 20,000 amps. So a 'whole house' protector should be at least 50,000 amps.

Current rating for a protector ballparks its life expectancy over many surges. Quality of and connection to earth ground determines protection during each surge.

 

[volleyball]

The best surge protection is multi phased. You are not fully protected by a unit at the panel. You need to have protection at the devices too.
I go simple at the panel and do appropriate at the equipment.

 

[westom]

The best surge protection is multi phased. You are not fully protected by a unit at the panel. You need to have protection at the devices too.
I go simple at the panel and do appropriate at the equipment.

Anything a protector might do at the appliance is already inside the appliance. Often a surge too tiny to damage appliances also destroys a grossly undersized protector. Then the naive assume "My protector sacrificed itself to save my computer." Total nonsense. An ineffective protector contains thermal fuses to disconnect protector parts as fast as possible. That surge remains connected to attached appliances. Superior protection routinely found in all appliances protected that appliance.

Protection is also done in layers. A 'whole house' (at the panel) protector is the 'secondary' protection layer. No protector does protection. Each protector is effective when it connects to what does protection. Protection is what harmlessly absorbs hundreds of thousands of joules - earth ground.

So the 'secondary' protection layer is a 'whole house' protector connected low impedance to earth. A picture demonstrates what informed consumers inspect for their 'primary' surge protection layer:
http://www.tvtower.com/fpl.html

How does a tiny and adjacent hundreds joule protector work during destructive surges? A hundreds joules surge is often converted by electronics into electricity to power its semiconductors. Grossly undersized and adjacent protectors do what for larger surges? They fail.

Protection is always about layers. The 'primary' and 'secondary' protection layers are defined by each single point earth ground. Superior protection already inside appliances is then not overwhelmed.

BTW, an adjacent protector sometimes compromises protection inside electronics. Another fact ignored by advertising that promotes near zero and ineffective 'at the appliance' protectors. A protector is only as effective as its earth ground. Where do hundreds of thousands of joules harmlessly dissipate?

 

[sberry]

I agree that money spent on gadgets should be proceeded by upgrading the actually ground. As I mentioned earlier I had some problems early on with phones and puter modems. Since I bonded it to better electrodes with a larger direct wire the phone co equipment did its job vs it hunting for a ground thru my electrically connected puter.
It used to be the phone co at demark survived and my strip supressors took a hit. Got a half a dozen of them in short order and now havnt had a problem in years. Really a problem due to the fact the phone installer doesn't understand a couple basics and in leu of that doesn't follow the instructions found in 880

 

[sberry]

At times there can be a real problem, service men see it on occasion but,,,,,,,,,,,,, this is about likng to need an inch air line so I don't lose speed blowing up a tire.
Most people I know never had a problem and the ones that did jump to the assumption about how it occurred and assume if they did something different the outcome would be different. Now because they didn't have another problem in the short term what they did must be right. Lightning really didn't "hit the well" but the well pump was the termination for a strike as the rest of the electric system was faulty and was not bonded to the casing properly, missing ground rods etc.

 

[sberry]

My phone co had a big ole copper sheathed cable come in, brings a strike right in and then,,,,,,,,,,,,,, no where to go except thru modem and to grounded puter case. Now I bond the sheath to the uffer,,, don't need the suppressor.

 

[sberry]

I like that Westom goes in to this. In more basic terms you want to give it a place to pass a strike thru direct so it isn't searching. On phones they call for 14 insulated wire I believe, I went a little farther and went 12. In some cases where there are primary and secondary electrodes they (as in minds greater than my own) want larger wire on the primary.

 

[sberry]

I forget the code art antennas are under but its worth a read thru as it may help understand the nature of the problem.

 

[volleyball]

Westom goes into some of the details but fails on several levels. He assume the unit is built into the machine. Also he assumes you are using some cheap unit at the devices. And that the panel is secondary. It is only secondary if the surge is generated past the panel.
You may only need a cheap unit for a simple appliance.
You need to assess your probability. And how much insurance you want. A house in a neighborhood where property is close to each other is less vulnerable than a place miles from the next user on the grid. Plus what kind of weather you get.

 

[bczygan]

This brings up another question.

Lightning protection.....

For not just antennas, but the whole house.

Nobody seems to have it anymore.

When I was working for a builder, we lost a 1/2 mil homearama house to a lightning strike and fire.

My house has the tallest trees in the neighborhood, all around it, which makes us a target.

And I want to install a tall Ham antenna.

 

[volleyball]

Lucky for you, your antenna will be the lightning rod. I think you will need some HAM's to offer suggestions.
When I did pro radio we grounded to the tower and that to ground rods.

 

[bczygan]

Lucky for you, your antenna will be the lightning rod. I think you will need some HAM's to offer suggestions.
When I did pro radio we grounded to the tower and that to ground rods.

The trees also can attract a lightening strike. I know that trees can also be protected with a system that shunts a strike to ground.

In my case, with trees overhanging the house, I can see a tree strike jumping to the house gutters and downspouts or the antenna and guy wires and then the gutters and downspouts. And then to metal storm windows or aluminum siding. Lacking a path to ground, it will try to get to any wet wood sheathing or framing, etc.

I already have the biggest TV antenna I could find, on a tripod, on a second floor roof. Time to get some protection on that!

 

[volleyball]

I don't like trees close to the house , especially if they are tall and or old. Maybe get rid of those that can damage the house.

 

[theoldwizard1]

And I want to install a tall Ham antenna.

I am sure your fellow Hams will talk your ear off on lightning protection ! Pun intended !

 

[bczygan]

I am sure your fellow Hams will talk your ear off on lightning protection ! Pun intended !

It's what we do........

 

[sberry]

Read the NEC on antenna.

 

[westom]

Read the NEC on antenna.

NEC only discusses what is necessary for human safety. Equipment safety means donig and *exceeding* what is required by the NEC.

For example, NEC discusses wire thickness because resistance is important to human safety. Equipment protection involves wire shortness because impedance is important for equipment protection.

Concept relevant to equipment grounding are discussed in a QST (ARRL magazine) July 2002 entitled "Lightning Protection for the Amateur Radio Station"

The purpose of the ground connection is to take the energy arriving on the antenna feed line cables and control lines (and to a lesser extent on the power and telephone lines) and give it a path back to the earth, our energy sink. The impedance of the ground connection should be low so the energy prefers this path and is dispersed harmlessly. To achieve a low impedance the ground connection needs to be short (distance), straight, and wide.
...
The goal is to make the ground path leading away from the SPGP more desirable than any other path.

Also relevant are Technical Notes from Polyphaser. NEC does not discuss this due to purpose of those NEC codes.

 

[westom]

I don't like trees close to the house , especially if they are tall and or old. Maybe get rid of those that can damage the house.

One long time observer of lightning strikes noted something rather curious. Tall white pines tend to protect a house from lightning. Nothing averts the strike (despite popular myths from the ESE insdustry). He noted that best white pines are those with capillary tubes that do not spiral as they rise inside the trunk. These trees tend to act as lightning rods. And in most cases, are not damaged when struck directly.

 

[volleyball]

I can see why white pines would tend to attract lightning. Straight, tall and lots of moisture. But if they get hit and fall on the house, is that better?
Trees are good. Just at a little distance.

 

[sberry]

We have lost a lot of these from lightning. We lost a couple in a fire, we lose one once in a while but some smaller ones have grown a bit in my lifetime. There were another half a dozen in my parents front yard that got hit over the years.

 

[westom]

I can see why white pines would tend to attract lightning. Straight, tall and lots of moisture. But if they get hit and fall on the house, is that better?

Most see the exception. Then assume that is the rule. As documented by the US Forestry Service, well over 90% of lightning struck trees have no appreciable damage. Rare is for a lightning struck tree to suffer catastrophic damage. Which is why that observer recommended planting white pines.

Trees located too far away would provide diminished protection.

Of course, better than an earth tree is a properly earthed lightning rod.