– 12 –
Cut and
re-terminate
cable here
after P1
reading
ZERO
FIBER OPTIC TEST SET
DISPLAY
SELECTOR
SWITCH
ON/OFF
SWITCH
20
μ
W
200
μ
W
2 mW
20 mW
Industrial Fiber Optics
LED
ACTIVATION
WAVELENGTH
(
λ
)
650 nm
850 nm
LED TURNS OFF
AFTER 10 MIN.
DETECTOR
10 meters
Total inital length
for reading P1
Plastic Fiber Optic Cable
Cutback
length
for
reading
P2
5 meters
1019.eps
1.
Put the protective cap on the “DETECTOR” receptacle and set the “DISPLAY
SELECTOR SWITCH” to 20 µW. Turn on the test set by pressing the “ON/OFF”
switch.
2.
If the meter does not read zero (± 0.02 µW), refer to the section titled “SERVICE
AND MAINTENANCE” and follow the “Zeroing” procedure. Remove the
protective cap.
3.
Set the “DISPLAY SELECTOR SWITCH” to 20 mW or the highest expected
power to be measured. Set the “WAVELENGTH “ switch to the closest value for
the optical source being used. For visible sources choose 650 nm; for infrared
sources select 850 nm. If you are using the LED in the Fiber Optic Test Set, select
650 nm.
4.
If you are using the built-in LED, remove the protective cap from the receptacle,
then insert one end of the connectorized cable. Otherwise install one end of
the cable into the external optical source. Insert the remaining connector into
the “DETECTOR” receptacle on the test set.
When making measurements with
un-connectorized cable ends or fi ber, gently insert them into the appropriate
receptacles on the test set. Do not apply pressure beyond what is required to
seat the ends or internal components may be damaged.
5.
Push the “LED ACTIVATION” button and allow one minute for the source to
stabilize. If you are using an external optical source, turn it on and make any
adjustments necessary to set the power level.
Observe proper safety precautions
as outlined in the SAFETY
section of this manual.
6.
Observe the LCD display for an indication or non-zero reading. If the reading is
zero or very low, rotate the ‘”DISPLAY SELECTOR SWITCH” counter-clockwise
(more sensitive scale) until the display gives a maximum reading without over-
ranging. Note the reading in µW or mW and record the result as
P
1
Figure 3.
Cutback approach
for measuring
attenuation
