could someone please help me to identify what is long white SMD with JR marking? I am trying to draw a schematics for better understandig how ethernet and PoE on this device is implemented.

It has near zero resistance and i could not google anything with JR marking witch would have this shape. Board function is Ethernet input overvoltage protection and PoE voltage extracting.

My best guess is that it is fuse but it is quite big one.

And i don't understand why there would be two of those - one is connected to +48V supply over ethernet and one is 0V. Both lines are separated from chassis grounding



1 Answer 1


Might be a fuse or a high power resistor. I found this as an example of fuse: https://www.alibaba.com/product-detail/Bussmann-fuses-TR3-TCP1-25-R_60711164349.html

fuse smd picture

  • \$\begingroup\$ ah, thank you it really appear like one you linked. Could you please share how did you find it so quickly? i have been googling for this part for an hour with no luck. \$\endgroup\$
    – nettle
    Jun 24, 2018 at 16:06
  • \$\begingroup\$ From experience i knew it could be a fuse, so i just googled "fuse jr smd" \$\endgroup\$ Jun 24, 2018 at 17:52

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.