How to monitor barns 300+ feet from home M1 system

dfwehman

New Member
Hi, we have an Elk-M1 Gold system for our home, works great. We have two barns about 350 feet away that we would like to connect to the system, just door contacts and motion. We ran four parallel lengths of CAT6 cable to the barns, but the Elk Tech could not get the remote expansion board to connect to the main panel. I do have a WiFi network that covers the house and barns using EERO mesh networking.
 
Do I need some type of signal booster to enable the expansion board to connect at this distance? Are you aware of any technologies that would allow us to monitor magnetic switches and motion detectors that would connect via WiFi so we can monitor the barns?
 
The M1 data buss that connects to the expansion units and keypads can have a total length of 4000 feet.  If you are using Catx cable to create home runs back to the panel, then each cable length has to be counted as double, because the signal runs out and back.  Still, you should have no problem making it work over a distance of 350 feet, as long as your other data buss devices don't have excessively long runs.
 
If you are near the 4000' limit, you could consider using the M1DBHR to create multiple data busses.  That's really the only way to get past the total distance limit.  The M1 uses RS485 protocol, and although there are third party RS485 extenders, they are known not to work with the M1.
 
If the expansion unit isn't working, double check the data bus termination to make sure it's set correctly.
 
If you have only a couple of contacts and sensors in each barn, you could consider using pairs of wires in the Catx cable to wire up zones directly and dump the zone expander (or put it back with the main panel, if you don't have zones available on the M1 itself). 
 
There are WiFi door and window sensors that will work with a cell phone app.  Just search Amazon for "Wifi door sensor" and you'll find several.  I can't speak to the quality of any of them.  I just know they exist.
 
Since you have these Cat6 cables running between buildings, have you done anything about putting surge protection against lightning strikes on them?  You should have that at both ends.  Otherwise, you risk blowing out your M1.
 
Do you have a remote power supply in the barn? If not, with that length of run, you probably don't have 12 volts at the far end to run the expander card.
 
Have you addressed surge protection on both ends of the cable runs?  
 
A cat5/6 cable run that long will act like a giant antenna and be prone to picking up surges from lightning that is close. It won't even need to be a direct strike to have problems. This is why it is generally recommended that you install fiber connections at that distance. Not so much because the signals can't travel that far over cat5/6, but because electrical surges won't travel over fiber.  
 
How is the building powered?  Is it via conduit?  Is it via the same conduit and if not how close are the CAT6 cables to the power cables?
 
lanbrown said:
How is the building powered?  Is it via conduit?  Is it via the same conduit and if not how close are the CAT6 cables to the power cables?
Hopefully not in the same conduit as that is against code.  It's against code run power and low voltage in the same conduit and overall a bad idea.
 
JimS said:
Hopefully not in the same conduit as that is against code.  It's against code run power and low voltage in the same conduit and overall a bad idea.
 
Right and it would also generate a lot of noise and make communication across the CAT6 nearly impossible.  That would explain why the OP has an issue.
 
If you hire an electrician to run the conduit and power, they wouldn't run the low voltage stuff as it would violate code.  Someone doing it themselves can run it in the same conduit as code is not something they think of.
 
What I did for the data bus is to run a direct burial cat-5e cable (Superior Essex 22 gauge part number PW52-846-75) between our house and shop (110 feet apart), the idea being to minimize signal degradation on the long run.
 
The house and shop are wired with standard 24 gauge Cat5e. There is underground PVC conduit between the two buildings, each end terminating in an exterior junction box. Standard and underground meet in the junction box and are terminated using RJ45 connectors. The cable ends each plug into a grounded ethernet surge suppressor at both buildings. Note that the 22 gauge cable probably uses different connectors and crimper to accommodate the thicker conductors than standard 24 gauge cable. I used ICC connectors and crimpers.
 
Ethernet surge suppressors are these:
 
https://www.amazon.com/gp/product/B00805VUD8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 
I don't know, for a fact, that these surge suppressors are really effective in this RS-485 application but they don't seem to hurt. My original plan was to use optical isolators between underground and house/shop at each end but they didn't work. My goal is to find out why the optical isolators didn't work, and fix if possible, but it's down the list a way.
 
In the remote shop the data bus connects to an Elk P212S which supplies power and battery management for the devices you place there. I have input and output expanders there for motion sensors, water leak sensors, man door and overhead door sensors, and heat and CO sensors.
 
That's about it. It's been working fine for six months now.
 
The only suprise was my error. The house has a whole house backup generator, the shop does not. During a 5-day power outage the P212S battery got low and shut off (as it's supposed to), triggering a lot of alarms in the house that is powered by a generator. So I need to come up with a way to keep that panel powered during outages.


 
 
lanbrown said:
Industrial grade RS-485 surge supressor:
https://www.phoenixcontact.com/online/portal/us?uri=pxc-oc-itemdetail:pid=2762265&library=usen&tab=1
 
I use their Cat6A surge suppressors on serval pieces of network equipment.  I mount them on a 35mm DIN rail which is then grounded using another product of theirs to accomplish this.
 
I even use one of their 24VDC DIN rail surge suppressors for a push to exit button on a gate outside.
Thanks! I'll check them out. I had bought a couple of B&B Electronics units that seemingly should have worked and am very curious why they didn't, so my plan was to put a scope on it and look at turnaround times. Still might, but having a plug and play fix makes more sense, and then I can add a test section to the data bus and test it there.
 
RS-485 the voltage is going to be in the 12VDC range whereas Ethernet can be 12VDC, if you get into PoE then you can have 56VDC on the line.  Ethernet is also 4-pair compared to RS-485 which can be two-pairs in the full duplex setup.
 
If you look at the Ethernet surge suppressor you listed at Amazon; it listed this:
  • Aluminum Case,Ground Wire 12AWG,Line-Line Line-Ground Protection,Bidirectional Clamping,5KA 8/20μs
 
 
The Phoenix Contact can handle more:
 
Nominal discharge current In (8/20) µs (line-line)

10 kA

Nominal discharge current In (8/20) µs (line-earth)

10 kA

Pulse discharge current Iimp (10/350) µs

500 A

Output voltage limitation at 1 kV/µs (line-line) spike

≤ 22 V

Output voltage limitation at 1 kV/µs (line-earth) spike

≤ 600 V

Output voltage limitation at 1 kV/µs (line-line) static

≤ 22 V

Output voltage limitation at 1 kV/µs (line-earth) static

≤ 600 V

Output voltage limitation at 1 kV/µs (line-signalground) static

≤ 22 V

Residual voltage at In (line-line)

≤ 19 V

Residual voltage at In (line-signalground)

≤ 19 V

Voltage protection level Up (line-line)

≤ 22 V

Voltage protection level Up (line-earth)

≤ 600 V

Voltage protection level Up (line-signalground)

≤ 22 V

Response time tA (line-line)

1 ns

Response time tA (line-signalground)

≤ 1 ns

Response time tA (line-earth)

≤ 100 ns
 
The Ethernet surge protectors I use are all Cat6A, even for things that are only 100Mbps.  If I ever need to repurpose them, it can support anything I would need it handle.
 
https://www.phoenixcontact.com/online/portal/us?uri=pxc-oc-itemdetail:pid=2908726&library=usen&tab=1
 
Nominal discharge current In (8/20) µs (line-line)

100 A

Nominal discharge current In (8/20) µs (line-earth)

2 kA (per signal pair)

Total discharge current Itotal (8/20) µs

10 kA

Nominal pulse current Ian (10/700) µs (line-line)

≤ 40 A

Nominal pulse current Ian (10/700) µs (line-earth)

≤ 160 A

Output voltage limitation at 1 kV/µs (line-line) spike

≤ 85 V (PoE)

Output voltage limitation at 1 kV/µs (line-earth) spike

≤ 700 V

Output voltage limitation at 1 kV/µs (line-line) static

≤ 9 V

Output voltage limitation at 1 kV/µs (line-earth) static

≤ 700 V

Residual voltage at In (line-line)

≤ 15 V

 

≤ 100 V (PoE)

Voltage protection level Up (line-line)

≤ 9 V (B2 - 1 kV / 25 A)

 

≤ 100 V (B2 - 1 kV / 25 A - PoE)

Voltage protection level Up (line-earth)

≤ 900 V (B2 - 4 kV / 100 A)

 

≤ 700 V (C2 - 4 kV / 2 kA)

Response time tA (line-line)

≤ 1 ns

Response time tA (line-earth)

≤ 100 ns
  •  
 
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