Kingfisher KI 7340 Series, Руководство по эксплуатации и техническому обслуживанию

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KI 7340/7740 UM-12
18
REMOTE AND LOCAL REFERENCE METHODS
Instruments should be referenced prior to making loss measurements.
KI7340C/7740C Series support both local and remote reference
methods.
The remote reference method is useful for long distance testing.
Although this method has slightly lower accuracy compared to local
referencing, it is quite adequate for general link loss testing.
The local reference method provides high accuracy and is very
efficient for short distance loss testing, where both ends of the system
can be accessed readily by one meter, eg. patch leads testing.
Note: when setting the reference value, use test leads with a similar
fiber type to the system under test. This is particularly important for
multimode systems. Also, connector loss between the patch lead and
source port will be added to the final loss measurement, so care
should be taken to use test leads in good condition with clean
connectors.
Remote Reference method
For two or one direction testing involving two instruments, referencing
should be independently performed on both Loss Test Sets. The
following will set reference at all wavelengths:
•
Connect the Light Source /Two Way /ORL port to the Power
Meter port of the same instrument.
•
Select [POWER], [Autotest], [Abs/Rel] and then press [Set
Ref] for 3 seconds. Meters will display ‘BUSY’ and then 0.00
dB R.
Figure 1. Remote reference set up
Local Reference method
Referencing is performed on one of the instruments, which will set
reference at all wavelengths on both Loss Test Sets:
•
Connect the Light Source /Two Way /ORL ports of the
instruments.
•
Select [POWER], [Autotest], [Abs/Rel] and press [Set Ref]
for 3 seconds. Meters
will display ‘BUSY’ and then 0.00 dB
R.