Fiber optic couplers and other questions

[tigerwillow1]

I'm looking at a ~300 foot fiber run, about 100' inside building 1, 100' in a buried conduit, and 100' inside building 2. I could pull a 300' run of outdoor cable, but I'd prefer to break it into 3 sections to keep the cost of the outdoor cable down, and to make repair easier and less costly if the cable gets physically damaged. I'm not finding any good information about the pros and cons of using couplers, for instance these: Amazon.com: Fiber Optic Cable Adapter/Coupler LC-LC Duplex Multimode 5 Pack: Home Audio & Theater

For anybody who can offer real world experience, I've got 4 questions:

1. Is there any good reason to not break the cable run into 3 sections using pre-terminated cables and couplers? I expect insertion losses. A 300' run is really short for fiber, so I'm assuming I'd be able to easily tolerate the insertion losses.

2. I'm partial to LC connectors, with absolutely no experience to back that up. Is there a clearly better choice?

3. Based on what I read, OM1 multimode cable will easily carry gigabit ethernet over 300'. Is there any reason I should use a higher level cable?

4. Are there any particular low-cost wired ethernet to fiber media converters that are highly recommended?

 

[LT20]

For anybody who can offer real world experience, I've got 4 questions:

1. Is there any good reason to not break the cable run into 3 sections using pre-terminated cables and couplers? I expect insertion losses. A 300' run is really short for fiber, so I'm assuming I'd be able to easily tolerate the insertion losses.

- Most of my experience is with SM (singlemode) fiber. I'm inclined to think that MM is a bit more forgiving for dust in the connections due to multiple pathways throughout the core etc. Dust, oil from skin, lint, etc. is the enemy when it comes to mechanical splices. Lint free wipes and isopropyl alcohol are a good idea for final cleaning before connection.

2. I'm partial to LC connectors, with absolutely no experience to back that up. Is there a clearly better choice?

- a LC UPC (ultra polish connector) will suffice. If you were to ever need to use high power lasers for longer distances, you might consider going with an APC (angle polished connector) of any form such as SC, LC, ST, etc.

3. Based on what I read, OM1 multimode cable will easily carry gigabit ethernet over 300'. Is there any reason I should use a higher level cable?

-The media converters will probably be what limits your throughput, not the glass.

4. Are there any particular low-cost wired ethernet to fiber media converters that are highly recommended?
-I don't have any direct experience with media converters, but I know someone who does, I'll try to ask them tomorrow.


Is there any particular reason that you feel you need to use the OSP (outside plant) fiber? Do you think there will be significant resistance to pulling the fiber through the 100' conduit? I've worked on glass that has been in water-logged conduits for 20 years. The water had permeated the sheath, and gotten to it's core. Other than the higher attenuation, it was still handling traffic well. It didn't like to fuse well, but still worked. If you can safely install it in one piece, you might be able to get away with running inside plant fiber to save some costs. My personal recommendation is to try your best to avoid any unnecessary mechanical splices.

- Lonnie

 

[user2600844]

I do fiber, why do you want to use fiber on such short runs? CAT6 wiring is specd out for up to 100 meters (328 feet) at a gig. Also wireless would work good on short runs, all this would probably be less hassle than fiber at 300 feet. OM1 would work ok. Also ethernet to fiber converters are a little spendy. Just be sure to use Multimode converters. OSP cable is good for water, sun, weathering, ect, that makes cost go up even more. But simple indoor/ outdoor rated cable should be good if used for small office or home. LC connectors are nice because they are small, but a connector is a connector, it does not affect speed, just be sure your connector matches to the connector on the fiber to ethernet converter.

 

[tigerwillow1]

Good info in both posts, thanks. The reason for fiber is lightning protection. I view using surge protectors as maybe they'll help or maybe they won't, while fiber gives 100% positive protection. The two buildings are a bit over 100 years old, and there's not a decent ground connection to be had anywhere. We lost a bunch of equipment to a lighting hit a few years ago, and I don't want to add to the risk with the network connection.

 

[KC8FLB]

Not sure for longer lengths but om4 patch cables are the same or less cost as om3,2,1 and supposedly technically superior and backwards comparable. I am running brocade 6450 switches 4 sfp+ plus copper gb ports ($100) and mellanox Connectx-3 dual port qsfp+ nics with sfp+ adapters $40 total (hp oem flashed to latest mellanox fw) and it’s working great. Bought all the fiber from fiber store.