홈 > 지원 > 지식 베이스

Set Reference on fiber - how often do I need to do this? DTX-MFM2

A common question asked is how often you need to set the reference on your fiber modules. The question is typically generated by the fact that the remote will power down automatically after 30 minutes to preserve the battery. (It is important to note that the Power Down setting in the DTX Main Unit does not affect the remote unit) So if you are more than 30 minutes between patch panels, the remote is going to power down. Is this a problem? Do I need to run/drive faster between panels? Practically speaking, no.

If you are seeing negative loss readings, please review this article.

You must reset the reference when:

  • The test reference cord has been removed from the output port.
  • After the test reference cords have been cleaned AND inspected.


If the remote or main unit powers down, simply power them back on and continue testing. Not convinced, try the following: 

  • After allowing the main and remote sources to stabilize (at least 5 minutes, more if colder), set your reference. 
  • Rotate the dial back to AUTOTEST and press the TEST key. View the loss for each fiber: 
     
    R to M Loss Check with No Loss   M to R Loss Check with No Loss
     
  • If the sources have been allowed to stabilize, you should see 0.00 dB as in this case. If not, wait 5 minutes, Set Reference again and run the TEST once more.
  • Power down both units and leave them switched off for 60 minutes.  
  • Power the units back up and repeat the test by pressing the TEST key again. View the loss for each fiber:
     
    R to M Fiber Loss Check   M to R Fiber Loss Check
     
  • The change is no more than you would expect if you had left the units on.*
  • Power down both units and leave them switched off for another 60 minutes.
  • Power the units back up and repeat the test by pressing the TEST key again. View the loss for each fiber:
     
    R to M Fiber Loss Check for Repeat Test   M to R Fiber Loss Check for Repeat Test
     
  • Again, the change is no more than you would expect if you had left the units on.

You will observe more variability by not cleaning your fiber test reference cords throughout the day (if the connectors you are testing are dirty) than the unit powering off for 60 minutes. If you are observing variable test results, first visually inspect the connectors you are testing and then your test leads. Then, verify the performance of your test reference cords as described in the following knowledge base articles: