SFP+ for short distance?

[Mr. Cucumber]

Have two SFP+ modules (20KM transceivers) and A 5m duplex LC LC single mode cable.

So I was wondering if I connect the modules together will I burn out the diodes on each end (the RX part) 

 

LRXP8510-X3ATL

[Windows7ge]

Ripping someone else's words from a website:

Quote

Your biggest risk comes from Single Mode ER (40 Km) and ZX (80 Km) optics, which can overdrive and even burn inputs without sufficient attenuation.

 

There is no risk of burning Multi Mode optics, as long as you're connecting MM to MM.

 

I know 850nm 300m multi-mode SFP+ transceivers can be had for $16/piece. I don't know how greatly single-mode would differentiate but I'd like to believe it can't be much worse. 

[Mr. Cucumber]

4 hours ago, Windows7ge said:

Ripping someone else's words from a website:

 

I know 850nm 300m multi-mode SFP+ transceivers can be had for $16/piece. I don't know how greatly single-mode would differentiate but I'd like to believe it can't be much worse. 

So, should I go with a DAC cable?

[Lurick]

I'm a bit confused, the optics you mention in bold are multimode 300m optics but you also mention having 20km optics.

For the multimode optics no, you cannot burn them out.

For single mode only the super long range stuff is at risk over short distances. I've got some 2km LR optics back to back in the lab right now over 1m fiber, have been for 6 months, and no issues.

[Windows7ge]

3 hours ago, Mr. Cucumber said:

So, should I go with a DAC cable?

I mean, I prefer fiber but for such a short run DAC is an option. Just make sure you buy the correct type otherwise it may not work at all.

[beersykins]

As per others, where do you see 20km?  The part number listed is for MMF optics.

 

Twinax can be cheap if buying new, but since you already have optics you could probably swap for a MMF patch and just call it done.

[Mr. Cucumber]

23 hours ago, Lurick said:

I'm a bit confused, the optics you mention in bold are multimode 300m optics but you also mention having 20km optics.

For the multimode optics no, you cannot burn them out.

For single mode only the super long range stuff is at risk over short distances. I've got some 2km LR optics back to back in the lab right now over 1m fiber, have been for 6 months, and no issues.

I made a mistake (it is a 300m MMF tranceiver)

Thanks for pointing it out

[Lurick]

24 minutes ago, Mr. Cucumber said:

I made a mistake (it is a 300m MMF tranceiver)

Thanks for pointing it out

Ah, then you're completely fine.

I've got back to back over 1m MMF 10G, 40G, and 100G, transceivers that have been hooked up for a long time with no issues. Some for like 3+ years