EXFO FTB-3930 MultiTest - Manual (Page 83)

Multifunction Loss Tester 77
13 Troubleshooting
Solving Common Problems
Problem Possible Cause Solution
During offset nulling, you
get the following message:
“Light detected during
nulling.”
Light reaches at least one
detector (power meter or
F
AS
T
ES
T).
Ensure protective caps are
tightly screwed on F
AS
T
ES
T
and power meter ports and
perform the nulling again.
Do not use rubber cover.
When using the power
meter, you get Power Too
Low or Power Too High.
Power of the signal
received at the power
meter port is outside its
measurement range.
Check the connections.
Ensure you use the proper
fiber and connector type and
that you use your power
meter within specifications.
When measuring ORL, you
get Too Much Power.
Measured reflected power
is higher than emitted
power. The ORL reference
is incorrect.
Always perform ORL
reference before each ORL
measurement.
When measuring ORL, you
get ORL exceeds.
Reflection is below
sensitivity of ORL meter.
Perform an ORL zero
measurement to increase the
sensitivity of the detector.
Ensure mandrel is correct and
that patchcord and
connectors are in good
condition.