I'm working on a security cam system wired with a pair of fibers. One is transmit and the other receive. It's converted at the camera location with a AFI PoE media converter. The fiber is mulitmode 62.5 with ST connectors. I need to know what the specifications are for the light levels on each fiber. Both transmit and receive. I can't find those specs anywhere.
FIber optic power level question
- Thread starter Noovis
- Start date
Michelin Man
Getting the hang of it
How long is a piece of string?
If you have the model number that would help you. We don't have the information to be able to tell you.
If it's running ST connectors it must be pretty old gear. Multimode fiber is usually run at 850nm.
Why do you need to know light levels? You're going to need an OTDR or other expensive test equipment to see power output.
I'm curious as to why it's wired up on fiber to begin with.
If you have the model number that would help you. We don't have the information to be able to tell you.
If it's running ST connectors it must be pretty old gear. Multimode fiber is usually run at 850nm.
Why do you need to know light levels? You're going to need an OTDR or other expensive test equipment to see power output.
I'm curious as to why it's wired up on fiber to begin with.
Fiber is used because it's superior to copper. I need to know light level specs because the client is having issues with their cameras and they want to be sure it isn't due to attenuation.
The fiber connects the head in equipment to the remote camera locations.
The fiber connects the head in equipment to the remote camera locations.
Wow, talk about inappropriate use of technologies. Copper is likely to work fine at those distances. But now that they have run data and electric power separately anyway, you might as well keep using fiber for data. LOL.
I would suspect you have either a bad media converter (or more than one, because even absurdly high priced items can have high failure rates) or the fiber is damaged or maybe even the ends are just dirty. I would try replacing the media converters first, and if that doesn't help then run new fiber or switch to copper.
Sorry I can't be of any more help than this. I have zero experience with fiber optic networking because as of yet all my needs are met by copper for short distances and wireless for long distances.
I would suspect you have either a bad media converter (or more than one, because even absurdly high priced items can have high failure rates) or the fiber is damaged or maybe even the ends are just dirty. I would try replacing the media converters first, and if that doesn't help then run new fiber or switch to copper.
Sorry I can't be of any more help than this. I have zero experience with fiber optic networking because as of yet all my needs are met by copper for short distances and wireless for long distances.
Michelin Man
Getting the hang of it
It sounds like you're using fiber as it is an existing installation because its using ST connectors and all the cables are already run.
I just googled the model number and came up with the specification sheet.
https://www.surveillance-video.com/media/lanot/attachments/customimport/MX-46-FX-ST-POE-HP.pdf
From what I can see running single MM 62.5 fiber its at 1310/1550nm (which is odd over MM fiber), and at 1310nm for dual fiber runs. Max range is 2km and a loss budget of 11db. Seems to have every bit of information you need to know.
I would suggest cleaning every connector/socket with the proper wipes and solutions, check for damaged cables etc.
Unless you have an OTDR, and know how to use it. Because you will need one if you want to troubleshoot fiber installations.
If you need to start splicing connections and etc, you're going to need even more tools. Eg using a cam splice or a fusion splicer.
I just googled the model number and came up with the specification sheet.
https://www.surveillance-video.com/media/lanot/attachments/customimport/MX-46-FX-ST-POE-HP.pdf
From what I can see running single MM 62.5 fiber its at 1310/1550nm (which is odd over MM fiber), and at 1310nm for dual fiber runs. Max range is 2km and a loss budget of 11db. Seems to have every bit of information you need to know.
I would suggest cleaning every connector/socket with the proper wipes and solutions, check for damaged cables etc.
Unless you have an OTDR, and know how to use it. Because you will need one if you want to troubleshoot fiber installations.
If you need to start splicing connections and etc, you're going to need even more tools. Eg using a cam splice or a fusion splicer.
CamFan
Getting the hang of it
You don't need an OTDR. Nice to have, but not needed.
Get yourself a optical fiber meter that works at least with 1310 nm.
Disconnect the fiber from the TX and measure the launch strength at the device's TX output in db. Then reconnect fiber at the TX end only and go to the far end of the fiber and measure the strength before it hits the RX. That db reading should be within 11db of launch to be in your budget. Hopefully within 7-8 db.
Sometimes you put a barrel at the far end and just loop the signal back to check the full run of fiber.
It would be better to know the minimum launch strength of the TX in case you have a bad laser/LED. But if measure enough devices, you will have an idea of the launch strength.
Clean all connections, get an FIS fiber cleaning kit for ST. Clean every time before you patch. Minimize any fiber joints, you can see up to 2db loss in each joint, more if they are dirty.
Don't ever zip tie fibers, pinching them is really bad.
Watch for minimum bend radius, sharp corners. Can you visually inspect the fiber run? Who ran the fiber?
What exact fiber are you using? Who terminated the ends? Are you using any fiber barrels? What is the spec on the fiber ends(PC, UPC)?
Are you having issues on short runs? I've seen gear not happy with too much signal, so you have to use an attenuator. Rare, but a possibility.
As a rule with fiber, ALWAYS run extra strands. I usually run a TAC-4 when I need only 2 strands. Future proofing and redundancy.
I've worked with 500-1000 ft runs up to a few miles. Mostly with ST singlemode. Never trust old fiber unless you know who ran it, how they ran it. You need the right tools for measuring, cleaning, polishing and terminating. You also need to know how to use the tools. I don't polish or terminate, just know when to call in the fiber techs.
I use fiber only when copper won't reach. The extra hassle, cost of fiber, and having one more thing to fail is not worth it for short runs.
Get yourself a optical fiber meter that works at least with 1310 nm.
Disconnect the fiber from the TX and measure the launch strength at the device's TX output in db. Then reconnect fiber at the TX end only and go to the far end of the fiber and measure the strength before it hits the RX. That db reading should be within 11db of launch to be in your budget. Hopefully within 7-8 db.
Sometimes you put a barrel at the far end and just loop the signal back to check the full run of fiber.
It would be better to know the minimum launch strength of the TX in case you have a bad laser/LED. But if measure enough devices, you will have an idea of the launch strength.
Clean all connections, get an FIS fiber cleaning kit for ST. Clean every time before you patch. Minimize any fiber joints, you can see up to 2db loss in each joint, more if they are dirty.
Don't ever zip tie fibers, pinching them is really bad.
Watch for minimum bend radius, sharp corners. Can you visually inspect the fiber run? Who ran the fiber?
What exact fiber are you using? Who terminated the ends? Are you using any fiber barrels? What is the spec on the fiber ends(PC, UPC)?
Are you having issues on short runs? I've seen gear not happy with too much signal, so you have to use an attenuator. Rare, but a possibility.
As a rule with fiber, ALWAYS run extra strands. I usually run a TAC-4 when I need only 2 strands. Future proofing and redundancy.
I've worked with 500-1000 ft runs up to a few miles. Mostly with ST singlemode. Never trust old fiber unless you know who ran it, how they ran it. You need the right tools for measuring, cleaning, polishing and terminating. You also need to know how to use the tools. I don't polish or terminate, just know when to call in the fiber techs.
I use fiber only when copper won't reach. The extra hassle, cost of fiber, and having one more thing to fail is not worth it for short runs.
whoslooking
IPCT Contributor
And the pain in ass that 62.5 it so thin and snaps so easy.
But with fast fit connectors easy to repair.
But with fast fit connectors easy to repair.
Michelin Man
Getting the hang of it
For any serious diagnosis you need an OTDR. Doesn't mean you need to buy one, you could probably rent them out. Otherwise without an OTDR you won't know where the fault is. Then you end up wasting more time.
That's after you get past the basic diagnosis and still haven't found the issue.
Even then, if its cheaper to re-terminate/replace certain sections do that and try again. So basically what I'm saying is before you buy anything do the basic checks first.
Try other patch leads in place of the ones you have now, clean, visually inspect, all cables and connectors. I have seen some nightmares in server rooms and patch panels where fiber runs have been stapled down, bent past its minimum radius and what-not. I'm surprised it still worked.
That's after you get past the basic diagnosis and still haven't found the issue.
Even then, if its cheaper to re-terminate/replace certain sections do that and try again. So basically what I'm saying is before you buy anything do the basic checks first.
Try other patch leads in place of the ones you have now, clean, visually inspect, all cables and connectors. I have seen some nightmares in server rooms and patch panels where fiber runs have been stapled down, bent past its minimum radius and what-not. I'm surprised it still worked.
ST doesn't necessarily mean it's old equipment, nor does OM1 mean it's old fiber cabling.
OM1 62.5/125 fiber with ST connections is pretty standard for Industrial applications still and will usually be 1300/1310nm wavelength devices. We use a good bit of B&B Electronics FOSTCDRI-PH-MT fiber to RS-485 media converters over OM1 with ST connections. For certain applications the twist lock ST is preferred. Most of the electrical supply houses (Mayer Electric and Accu-Tech) around here pretty much only keep OM1 in stock for Indoor/Outdoor Tight Buffer Plenum rated fiber. Typically General Cable or Superior Essex.
Our latest installs are Hitachi OM3 50/125 to take advantage of the bend insensitive corning clear curve glass , but it is a non stocked item and just order large spools. Corning Unicam connectors for everything and never any issues with ST on OM1, OM2, OM3/4 or SC through the range as well. Just depends on the application and equipment.
To the OP, CamFan pretty much set you in the right direction. Have you checked to see if you have a pinched or broken fiber anywhere with at a minimum a VFL? That would be your cheapest tool to start with on troubleshooting. I've gone back to check installs a year or two later in chiller plants after maintenance staff have been putting their hands in my panels and come across what looks like good fiber, but putting a VFL on the strands makes for quick spotting of a damaged strand. I'll usually just cut off the damaged strand just above the break and terminate another strand on both ends (never know WTH they have done other than the 1 break) if I had not already on original install and use that. We usually run 6 strand for 2-4 strand requirement jobs and 12 strand for 6-10 strand requirement jobs. If connections have been cleaned and VFL turns up nothing and you are still having issues, it may be faster to pull down the media converters and test them with known good (and tested) patch cables first before trying to purchase or rent test equipment. Past that, it is all tier 1 and tier 2 testing of the cabling. Easier to just post links rather than explaining since it does not sound like you have done much with fiber optics.
https://www.bicsi.org/uploadedfiles/PDFs/Presentations/Region_Events/canadian_Lachine, QC_4-27-11/Understanding Tier 1 Reference Methods for Fiber Certification - Ron Groulx.pdf
http://www.cablinginstall.com/articles/print/volume-21/issue-10/features/tier-1-and-tier-2-testing-troubleshooting-and-documentation.html
Perhaps this may help, http://fiberu.org/
good luck...... Might be cheaper to bring in a datacom group as a subcontractor.
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