At Home In The Woods

[Obed]

This week the electrician will run a conduit between the basement and the attic so that we have the option to run a wire to the attic for a 100 A sub panel later if case we ever want to finish the upstairs. We are almost ready for insulation work to begin - except we haven't picked the insulation sub yet.

Today we went and looked at a stone mason's work. A club house he stoned with stacked stone is in the attached picture. We will have stone on the dining room in the front of the house. The stacked stone on our house will not be as rustic looking as that in the picture. We had some trouble finding masons near Knoxville who will lay real stacked stone. Most of the stone masons near the city only lay the fake stone. We had get farther away from town to find people who have experience laying real stone.

We need to decide on insulation, stone, siding and gutters, drywall, and painting subs. We have most of the estimates but have not chosen the subs yet.

 

[dstig1]

Low Voltage Boxes


I had considered hiring out running the Cat 6 cabling but decided against it. I just don't think I would be satisfied with how the work would be done. There are specific rules about how close to run the wiring to existing electrical wires, etc. in order to prevent network noise. I'd rather run the wiring myself to make sure its done the way I want it. For example,

that go between the garage door openers and the control box. While running the blue Cat 5 wire right beside the yellow electrical wires might work for a garage door opener, that's a no-no for network wiring.

And you have another problem. Running LV and power wire in the same holes is a code violation (or should be - things do vary by area). If the insulation is breached, you can have 110V on your LV system (or 220V, depending on what the wires are carrying). Dat be bad. Insulation can get melted as the electrician pulls wire through holes due to friction (I've seen it happen) which is the base problem. Separation into different holes is a simple and bullet proof preventative.

The electrician should know better, frankly. What I see is laziness in not wanting to drill an extra hole. Unfortunately this is all too common in residential wiring. And that is a great reason to do it yourself.

-Dave

 

[shane]

I know there are a lot of people who believe that the incredible human body occurred as a result of pure chance. Personally, watching the thorn work its way out of my thumb makes it very difficult for me to conceive that such an amazing capability is complete luck. I believe a designer purposely formed the body in a way so that it can self-heal itself.

I give this a thumbs up!!!

 

[Obed]

For the security contacts for the doors, should I get normally open or normally closed contacts?

I'm trying to get some information on a good home automation system for our house. Does anyone have any suggestions? I'd think that I would want something that is not bare bones. I'm kind of thinking it would be good to have a system that you can connect to with your computer, maybe even over the internet, but doesn't require a computer to keep running.

Thanks,
Obed

 

[dstig1]

For the security contacts for the doors, should I get normally open or normally closed contacts?

Thanks,
Obed

I'm not sure if it matters. I have to imagine every alarm system out there can handle both (or has a version that can). Ask a couple of the alarm contractors you talked with if they care one way or the other. If everyone says one thing, there ya go. FYI, I checked our door sensors and they appear to be closed when the door is closed. Not sure if they call that NC or not in this case (i.e. what is "normal" in Normally closed? When the magnet is in contact or when nothing is in contact?)

-Dave

 

[eepete]

All my door sensors are set up such that the contacts are closed when the door is closed. While I'd call this NC, a few extra words can avoid confusion: "I want it so that when the door is closed the switch contacts are closed."
Three wins there:

1) If the "bad guys" cut the wires, it looks the same as a door entry.
2) If the wiring fails, you know right away because it looks like the door was left open. If the switch is wired so that it's open when the door is closed and then you have wiring probelms, you don't know you're in trouble until you open the door and notice something didn't work right.
2) Usually, one wire is ground and the other is the input to the alarm or automation system. So when the contacts are closed, the input is at ground vs. just floating out there. So things like near lightning strikes, near radio signals (from hand held radios) don't affect stuff. There is a YMMV factor on this one and since the word "lightning" is in there I'm wide open for a lot of flack.

There is also a technique that uses what is called an End of Line (EOL) resistor. This would put a resistor (usually about 2.2K) across (in parallel with) the switch (which is at the end of the line). The security system then has a 2.2K pull-up resistor to +5 at the unit. So if the switch is open, the unit sees 2.5 volts. If the switch is closed, it sees ground. If the wire is cut, you see 5V at the input. It's a great system (the stuff I do supports this feature). With a simple switch and just two wires, you can tell three states: open, closed, bad/cut wires. The problem is you've got to get the resistor installed at the end of the line at the switch. Not too hard to do, but it has confused a few installers. As a side comment, I solder the wires at the wire-switch interface. A little tape (Scotch 33+ or 88) and then heat shrink. I don't want plastic wire nuts buried in the wall where I can't get to them. Now imagine that with a little axial resistor in there too :confused2:.

A seconds problem: I can't tell you how many commercial fire alarms I've seen that the EOL resistor at the panel. Of course, it does no good there. The installer was either lazy or stupid. And the poor owner has no idea.

A third problem: The value of the EOL resistor, along with the pull up voltage, follows no standards. So you have to decide what system you are using and then you are sort of locked into it short of tearing your door casings apart.

The key concept here is that you are aware of this approach. You can see where in a commercial setting, systems that can distinguish between wiring problems and sensor activation is a win. In a home setting, particularly with doors, the value is less clear. This technique can be used on any contact closure device such as smoke and motion detectors. But in those cases, you have access to the device and wiring with little difficultly.

As for a good home automation system, if you can't wait about 2 years for mine to be done, some units to look at are JDS Stargate and the HAI systems. You can google them. A good security system (and cheaper too) with some more advanced systems is made by Elk Products. You could start with that and then add the automation system later (like in two years....). I suspect this is a "post fog" matter, and if so we can talk some night when you're all nestled into you wonderful new house :thumbsup:.

Pete

 

[dstig1]

Cool - Thanks Pete, I learned something more there too.

 

[dcyrilc]

A seconds problem: I can't tell you how many commercial fire alarms I've seen that the EOL resistor at the panel. Of course, it does no good there. The installer was either lazy or stupid. And the poor owner has no idea.

Pete

Pete,

It may not all be the installers fault. My 15 year old panel at the farm called out in the owners manual for the resistors to be in the panel. This might be for a different purpose, but I remember that either the NO or NC configuration called for resisters in the panel. My panel did both and didn't care as long as the resistor was put in for the correct configuration.

 

[Obed]

There is also a technique that uses what is called an End of Line (EOL) resistor. This would put a resistor (usually about 2.2K) across (in parallel with) the switch (which is at the end of the line). Pete

Pete, You're a wealth of information. Thanks!

The security guy installs the security wiring this Wed. I may go with the HAI system. It uses 1K EOL resistors (optional) for the door contacts. What I'm trying to figure out is, do I put each door on its own zone or can multiple doors share the same zone? We have 5 exterior doors, plus the door to the basement and the door to the garage that we want contacts installed in. We will also install contacts on 2 interior doors per your suggestion. The HAI web site says to install an EOL resistor for a zone ( On the Omni/Omni Pro systems, you must use a 1K ohm end-of-line resistor for each zone input. With the Omni LT, Omni II, Omni IIe, and Omni Pro II, Lumina, and Lumina Pro, resistors are optional) . So do I put all 5 exterior doors on one zone, the door to the garage and to the basement on a zone, and the 2 interior doors on a zone? Or does each door go on a zone? I'm trying to figure out where the EOL resistors need to be installed. I'm guessing I will use contacts that are closed when the doors are closed.

Thanks for your help,
Ken

 

[eepete]

As for the doors and zones question:

In general, you want a single door that is the one you will use when the system is armed (ready to yell if someone comes in the house) and you are entering the house so you can turn it off. For most people, this is the door to the garage. There should be a keypad at this location.

If you thought you might sometimes enter via a different door that the garage than that door should be on it's own circuit (zone) too and there should be a keypad in that area too. So if you think you'd be out tractoring and then come in via your basement tractor garage, the basement door would be good to have. The basement door is also a good interior door for future alarm stuff just like your 2 interior doors you'll be wiring.

As for all your other doors, the decision to "string them together" into a zone vs. home run each door is (IMHO) an automation vs. alarm decision. For automation it's nice to have each door on it's own so you can announce which door is opening. When your daughter has learned to open doors, you'll appreciate knowing which door opened up. All the doors in my house are individually home runned.

In the HAI line, the Omni II systems have 16 contact closure zone inputs, so you'll be all set. On the Omni LT, thee are less but you can add up to 24 zones with add on boards. The wiring effort is virtually the same. Think about the work to run from door to door, vs. run from each door to your closet with the alarm/automation system in it. Not much difference.

Lots of people buy and install this system on their own, I know you can do that.

Finally, note that since your doors will be a normally closed contact, you can home run all the doors (so each door could be it's own zone) and then just series up the wires to connect a number of doors to one zone. It's all just one bit closed circuit until a single door opens. And each door can have an EOL resistor on it because it is normally shorted out when the door is closed. That way, you have the versatility of each door announcing but you can start out with a lower cost system will less zones in it. And if there is any kind of wiring failure, you aren't trying to figure out where/which door has the problem. This is another win with the pre-wire doing the contacts closed when door is closed approach.

The 1K resistor is fine. On my system, I use a 2.2K pull up. You can set the threshold voltage on the input so that it can work with any sized EOL resistor. Both mine and the HAI take the input, protect it, and run it to an A2D converter so it can see the 3 voltages that could be there (near gnd, middle determined by the EOL resistors, and near some pull up resistance).

Summary: Wire each door on it's own with a home run to the alarm panel, and put the 1K EOL resistor where you connect the wire to the magnetic sensor. The doors per zone can be figured out later.

Pete