drvnbysound
Senior Member
The maximum length (provided by the spec, I believe) is 328ft. It's not suggested/recommended to go beyond this, however I am certain of longer runs that have been in use for many years.
New Project - Need pointers so I get focused
- Thread starter tonti
- Start date
apostolakisl
Senior Member
tonti said:
I suggest asking an expert since I have no experience with metal structures, but my thoughts would be as follows:
1) Since the metal building is the first structure you are going to from the pole and there is nothing electronic between you and the pole, you could possibly be alright to have another ground at the metal building. Any ground induced current between the pole and the metal building should be harmless since there is nothing there but the service wires.
2) I am not at all familiar with code on electrifying a metal building. I don't know if it is required to tie the structure into the same ground as your electrical. If that is not required, then you should be able to isolate the ground for your electrical from the structure. There may be reasons that you can't or shouldn't do that, and I would be interested to hear the logic if someone does know.
I am surprised that your yard line from the pole to your service panel in the barn is copper. That must have been very expensive. All of my service wires are aluminum, only the branch circuits are copper. This is always the standard as I have seen it. Certainly you can not mix copper and aluminum in direct contact, but the service panels are designed to have aluminum feeds and don't put aluminum and copper in contact.
EDIT: And last thing, get yourself whole house surge suppressors at the main panel and the sub-panels. These are designed to block spikes on the hot wires (all of this grounding stuff we have been talking about does nothing for a hot wire surge). These spikes come in through the utility hook up and can be a result of the utility itself having a malfunction (transformer explosion) or a lightening strike on the utilitie's equipment.
pete_c
Guru
Yup; catXX is limited to ~ 100 meters (328 feet as mentioned above).
I helped friend on farm run direct burial cable between two house which actually is pushing the 300 some and still works fine with the house(s) networking interconnects. All homes on farm are owned by family (sister and brother).
I was also looking at using wireless originally. Long term though is to use wireless to an apartment building which is comcast connected in town some X miles away as currently he is using wireless broadband which only OK and now much overly subscribed.
Attached are are couple of drawings.
I helped friend on farm run direct burial cable between two house which actually is pushing the 300 some and still works fine with the house(s) networking interconnects. All homes on farm are owned by family (sister and brother).
I was also looking at using wireless originally. Long term though is to use wireless to an apartment building which is comcast connected in town some X miles away as currently he is using wireless broadband which only OK and now much overly subscribed.
Attached are are couple of drawings.
Attachments
Let the games begin.... I just purchased 5 minutes ago the ELK-M1GSYS4 for $479.75 at homesecuritystore.com. I also started laying out all sensor needs and discussed this with my 'government'. And, the best news is that my contractor starts framing the house next week. It's coming together! 
tmbrown97
Senior Member
Just for fun I'll also point out that I have a POE radio located at the end of a 720' run of Cat5e. I use a large POE injector at the head end, then a Midspan injector half-way up the hill (my conduit has a pull box in the middle just for this where it comes out of the ground) - then at the top it converts from 802.3af POE to this radio's proprietary passive POE - it's been in service for 18 months now... so there are ways around distance limitations. Alternative would've been running power and fiber separately.
Congrats on starting off the addiction!
Congrats on starting off the addiction!
All,
I need a quick pointer please before I order cable.
Why does the "Wiring 101" document point to a 22/4 cable for the contacts? Door contacts are only 18/2, is the window contact not the same concept of a magnetic switch. Shouldn't a 2 wire be sufficient?
Also - I plan to substitute the 22/4 for Cat5e (as suggested in Wiring 101), this makes logistics a lot easier. Anything to watch out here when substituting?
tonti
I need a quick pointer please before I order cable.
Why does the "Wiring 101" document point to a 22/4 cable for the contacts? Door contacts are only 18/2, is the window contact not the same concept of a magnetic switch. Shouldn't a 2 wire be sufficient?
Also - I plan to substitute the 22/4 for Cat5e (as suggested in Wiring 101), this makes logistics a lot easier. Anything to watch out here when substituting?
tonti
pete_c
Guru
Initially I started with Cat5e here. I ran into a couple of issues. (note this is more opinion than anything).
1 - cat5e footprint in the HAI OPII can got a bit excessive after 4-5 of them
2 - what colors / pairs I was using got to be difficult to manage (like dealing with a two color pair or 4 color set of wires that are easy to see?).
I then just went to using the 22/4 & 22/2 wiring in the midwest. The prewire done in FL was all 22/4 and 22/2 labeled to every window/ door. It was way easier to test and connect each zone in the HAI OPII can. In the midwest I did document and label wires; still having issues with the logic I used and why years later (mindset I guess) and its only been maybe 10 years plus.
I did the neighbors house post alarm panel install with originally wired loops everywhere. This was also difficult to work on having to first find out where everything was with no documentation using a toner and vom. I spent way more time doing this than the actual installation of the panel.
1 - cat5e footprint in the HAI OPII can got a bit excessive after 4-5 of them
2 - what colors / pairs I was using got to be difficult to manage (like dealing with a two color pair or 4 color set of wires that are easy to see?).
I then just went to using the 22/4 & 22/2 wiring in the midwest. The prewire done in FL was all 22/4 and 22/2 labeled to every window/ door. It was way easier to test and connect each zone in the HAI OPII can. In the midwest I did document and label wires; still having issues with the logic I used and why years later (mindset I guess) and its only been maybe 10 years plus.
I did the neighbors house post alarm panel install with originally wired loops everywhere. This was also difficult to work on having to first find out where everything was with no documentation using a toner and vom. I spent way more time doing this than the actual installation of the panel.
tmbrown97
Senior Member
Door/Window contacts use 2 wires; motion sensors, glass breaks, etc - things that need power - use 4 conductors.
If you have to, you can actually run multiple off much fewer conductors - for instance could run 3 contacts off 22/4 because all the grounds can be shared - and the ground from the power side of the motion can also be shared - but that's more for retrofit. If you're building now it's best to do it right from the start.
I agree with Pete's points above about it being bigger, plus the little solid wires are more prone to breaking.
You can run one wire across the house and split out then if you need to - just keep in mind that any splice points are a potential point of failure - especially if they're hidden in a wall somewhere. My absolute preference would be every single point home run back to the panel with the correct wire (22/2, 22/4) - then group logical windows there if you want (two windows on a wall into a single zone, for instance).
If you have to, you can actually run multiple off much fewer conductors - for instance could run 3 contacts off 22/4 because all the grounds can be shared - and the ground from the power side of the motion can also be shared - but that's more for retrofit. If you're building now it's best to do it right from the start.
I agree with Pete's points above about it being bigger, plus the little solid wires are more prone to breaking.
You can run one wire across the house and split out then if you need to - just keep in mind that any splice points are a potential point of failure - especially if they're hidden in a wall somewhere. My absolute preference would be every single point home run back to the panel with the correct wire (22/2, 22/4) - then group logical windows there if you want (two windows on a wall into a single zone, for instance).
I created a document laying out the sensors. It is a detailed 6 page review. Does someone want to review this for logic placement of sensors? If you want to do this please PM me.
I am reading up on the manual for the ELK-M1. I have split my 24 windows into 8 logical zones, I have 6 doors and 1 safe door that I want to monitor. So I am already using 15 of the available 16 zones - right? I will add later other sensors so I will purchase the extender M1XIN. But for now this leaves me with only one zone left.
I don't want to mess around with Smoke Detectors yet as the builder has to install his multiple ones as part of his requirement. They will be separate for now and I will replace them later. But I like to include three Glass Break sensors - is it possible to daisy chain them similar to the door/window sensors. Do I understand this right that the glass break sensor then go onto the 16th zone (daisy chained) and get power from VAUX (each separate power)?
As always - I highly appreciate all your help!
I am reading up on the manual for the ELK-M1. I have split my 24 windows into 8 logical zones, I have 6 doors and 1 safe door that I want to monitor. So I am already using 15 of the available 16 zones - right? I will add later other sensors so I will purchase the extender M1XIN. But for now this leaves me with only one zone left.
I don't want to mess around with Smoke Detectors yet as the builder has to install his multiple ones as part of his requirement. They will be separate for now and I will replace them later. But I like to include three Glass Break sensors - is it possible to daisy chain them similar to the door/window sensors. Do I understand this right that the glass break sensor then go onto the 16th zone (daisy chained) and get power from VAUX (each separate power)?
As always - I highly appreciate all your help!
BraveSirRobbin
Moderator
I'm sure someone will correct me if I'm wrong here; but, I thought there was some (NBFAA??) spec that wiring to security sensors could not be smaller (cross section diameter) than 22 gauge. IF this is true, this would throw out using Cat5 for this purpose.
Can you just use fiber between the buildings to isolate them from lighting strikes? Obviously you can for network. I wonder if a couple of these would work to extend the Elk RS-485 bus over fiber:
http://www.bb-elec.com/Products/Serial-Connectivity/Serial-Converters/Fiber-Optic-Converters.aspx
http://www.bb-elec.com/Products/Serial-Connectivity/Serial-Converters/Fiber-Optic-Converters.aspx
