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TrendNet Fiber Converters installation problem - please help

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symhelp

IS-IT--Management
Aug 12, 2009
53
US
I purchased 2 1000Mbps TX to 1000Base-SX Fiber Converters, TFC-1000MSC. Our fiber line has the old ST connections. So i purchased 2 1m Multimode ST/SC Patch Cable for each end. I plugged both network cables into 1000Mbps switches and i get nothing. the Link/Act is not lit up at all. I made sure i reversed th TX & RX cables like the installation guide says, i reversed them where they plug into the fiber connecters, hope thats right. please help! thanks!
 
make sure you are only flipping one end not both ends.
Can you see any light from either fiber?
 
Have you cleaned the optical connectors? Dirt and other debris can block laser light transmission.

It is VERY dangerous to stare into any fiber optic cable!! That laser can permanently damage eye sight. Since it is in the IR spectrum, you can't see it anyway!

Use the proper test equipment or the IR-B2 laser card detector to sense any laser light from fiber optics. Also, a simple test would be to loop the fiber connection back to the converters in either direction to find the fault using a patch cord. Make sure you have selected the right pairs on both ends.

....JIM....
 
I did not mean to insinuate you should stare at the laser .... I should have been more specific, good catch syquest.
 
I understand, but with the dumbing down of society anymore, you can't be too careful! You would be surprised what some people do!!

....JIM....
 
I have the Same units. The link lights work only when you have a FULL link end to end including the Ethernet devices.

Just linking the fibers won't light the link lights, Twisted pair patch cords have to be hooked up and linked at both ends
 
That must be a characteristic that is unique to the TrendNet unit. Other brands I have used don't work that way. To me, TrendNet's logic is confusing, and that would be a good reason to avoid that brand.

....JIM....
 
so i'm still having problems with these devices. maybe i have the cables plugged in wrong. i'm so confused at this point. I'm going to attach a link to 3 photos, a pic of the terminal boxes at each end and a pic of the converter box. maybe someone can tell me at least if i'm plugged the cables in the right way. i do have a gigabit switch plugged in on both ends and i still do not have any activity. Also i called TrendNet and they had me change the dip switches inside the boxes. Switch 1- On for Forced Mode & switch 2 -off for LLR disabled.

thanks for all your help!
 
So, let's start over! You should get both units and set them up next to each other for testing. You will need an SC/SC duplex or two SC/SC single fiber patch cords for testing. Use known good patch cords. Make sure the fiber connectors are clean! Re-enable the auto negotiate mode, switch 1 off. Connect two Ethernet devices, one to each converter. Then, see if you get any Link/Act indication.

What make/model is your gigabit data switch?
Does it have GBIC or SFP module capability?

You could have a defective unit.

....JIM....
 
ok, that's something i'll have to order, we don't have extra fiber cables, i guess that might be helpful if one of the cables would die on our other fiber connection. i just purchased the ones i'm using with the devices. also you mentioned a IR-B2 laser card detector earlier, any idea what the cost is involved with that?

how do you make sure they are clean, they had covers over them before i started plugging this into them.

one the one end we have a Cisco Catalyst 2960 switch and on the other i just put a little Netgear ProSafe 5 Port Gigabit switch.

thanks for your help!
 
Start at basic's use the green and the brown to start
at one end the make the green the xmit and the brown the rec,and reverse at other end green is rec and brown is xmit,hook up both your switches and see what you get, since you don't have a light meter, if this doesn't work swap out one fiber at a time.
compressed air will get rid of any dust on the connectors at least enough to get light thru.------------------
good luck!

PS Any time I see the blue/orange not being used I get a little nervous.
 
You can get the IR-B2 laser card detector from Fiber Instrument Sales, fiberinstrumentsales.com. They have everything fiber, including classes that are held around the USA during the year. Check the website for a schedule or call them.

Also, you MUST maintain clean connectors if you want the best performance from fiber cable systems! Here is a Corning document that provides some simple steps for the cleaning process:
If the Cisco C2960 has a GBIC socket, it would be better to use the GBIC module for fiber than a media converter. One less hassle when trying to troubleshoot a problem, and eliminates one more thing that can break.

For your fiber toolkit, having single SC/SC and ST/ST patch cords is a must for simple loop troubleshooting, etc.

....JIM....
 
so i haven't working on this in a few days and i went to look at one of the converters and the Link/Act light was blinking. This is the end side that is plugged into the Cisco switch. i got excited and thought it was magically working now. so i went to the other end but that side is not blinking. since i have one end blinking would you think that means the fiber connection is working just not the switch on the other end? the switch on the other end is a Netgear ProSafe 5 Port Gigabit switch. Do i need something programable on both ends? I have the cisco switch port right now set for 802.1Q Trunk.
Thanks for all your help!
 
Looking through the quick-start guide, there is a mention of a couple DIP switches, the second one was labeled LLR -- I'm not sure what that is, you might want to check your docs. Transition Networks products have a function called Link Pass-Through that will take down all three links (copper on either end and the fiber in the middle) if any of the links breaks. You can turn it off for troubleshooting though. Could the LLR be something similar?

Another thing to verify: are you using the same fiber everywhere? Those units look like they require multi-mode fiber. Assuming you have multi-mode installed between the patch panels, are the jumpers the same core diameter -- either 62.5 or 50 um? Have you tested the fiber strands you're using between the patch panels recently to verify they're still good?
 
thanks for everyone that posted! i ended up having someone come out to test our fiber lines. The one pair i was getting a green light on one end needed a replacement end on the other side. The top pair was working fine but i guess in all of my testing and switching the DIP switches i only had one set correctly, so it was user error on one pair and fiber failure on the other pair. just an fyi both green lights only came on when everything(both sides) was conneded properly. i'm not sure why i was getting a green connectivity light on one end when the other end wasn't working. still a mistery to me. i would not recommend these converters, because it has the only 1 connectivity light and you have no idea what is failing.
 
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