Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements
Webcast-Catalyst9k
New Member

Help on for short distance Single Mode cable

Dear Folks,

We have two switches with glc-lh-sm module inserted in each switch. Currently is under testing, I am using 3 meters of LC-LC singlemode patch cable to connect the switch, but the interface is still down. What could be possible happened, is the cable too short or can I use a multimode cable for the trial?

Thanks.

3 REPLIES
Hall of Fame Super Silver

Re: Help on for short distance Single Mode cable

You need to be mindful of your light level power requirements, especially when connecting laser-based optical components. If you significantly overpower an optical input, it can damage the receiver irreparably, requiring replacement.

That said, table 2 of the product data sheet (http://www.cisco.com/en/US/partner/products/hw/modules/ps5455/products_data_sheet0900aecd8033f885.html) indicates that the 1000Base-LX/LH modules (which includes the glc-lh-sm) have an an output power spec of -3 to -9.5 dBm and a recever spec of -3 to -20 dBm. Assuming both are operating in spec, you should be OK connecting back to back with a single mode patch cable.

Have you done the basic steps of:

a. confirming Tx-RX and Rx-Tx on the connection and

b. checking optical receive levels at both ends with an optical power meter?

Alternatively, one CAN use multimode fiber for these modules. (Reference the installation guide: http://www.cisco.com/en/US/partner/products/hw/modules/ps5455/prod_installation_guide09186a00803aa0da.html )

Hope this helps. please rate helpful posts.

New Member

Re: Help on for short distance Single Mode cable

Dear Friend,

As your used GBIC is type Long Houl (lh), you shoul have to use an 10 or 15 dB external attenuator per RX side.

May be you can use an MM patch cable, but is not very practice.

Good luck!

New Member

Re: Help on for short distance Single Mode cable

The problem solved with MM patch cable, thanks for the helps. I broke 3 pcs SM patch cord, what strange is, when I put the SM patch cord, the patch cord damage.

639
Views
8
Helpful
3
Replies
CreatePlease to create content