Extech Instruments PM200 User manual

User's Guide
PM200
Fiber Optic Power Meter
Introduction
Congratulations on your purchase of the Extech PM200 Fiber Optic Power Meter. The
PM200 is a high accuracy high resolution optical power meter. It is NIST traceable at
850, 1300, 1310 and 1550nm making it ideal for both single-mode and multimode fiber
testing. The PM200 can store up to 100 measured datapoints. This stored data can be
downloaded via the software to produce formatted certification reports. Careful use of
this meter will provide years of reliable service.

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Table of Contents
Specifications 3
Description 4
Operation 6
1.0 Applications 6
1.1 Precautions 6
1.1.1 Safety 6
1.1.2 Operational 6
1.2 Required Accessories 6
1.2.1 Cleaning Supplies 6
1.2.2 Patch Cords 6
1.2.3 Optical Fiber Adaptors 6
1.3 Typical Applications 7
1.3.1 Optical Power Measurement 7
1.3.2 Optical Loss Measurement 7
1.4 Optical Power Measurement 8
1.5 Optical Loss Measurement (Set Reference) 9
1.6 Optical Loss Measurement 10
1.7 Data Storage 11
1.8 Downloading Data into PC with Reporter Software 12
1.8.1 Standard Selection 13
1.8.2 Fiber Type Selection 14
1.8.3 Fiber Length Input 15
1.8.4 Connectors and Splices Input 16
1.8.5 Company Selection 17
1.8.6 Name Input 18
1.8.7 Summary View 19
1.8.8 Report Printing 19
1.8.9 Example Printout 20
1.9 Clearing Data 21
2.0 PC Based Meter Control 22
3.0 Battery Replacement 23
4.0 PM200 Data Storage Error Codes 23
Warranty 24

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Specifications
Optical Specifications
Detector Type Germanium (Ge)
Calibrated Wavelengths (nm) 850, 1300, 1310, 1550
Measurement Range (dBm) +5 to -60
Accuracy (dB) ±0.15
Resolution (dB) 0.01
General Specifications
Battery Life 100+ hours (9-volt)
Optical Connector 2.5mm universal
Data Storage up to 100 storage points
Download DB-9 serial
Software Reporter
Dimensions 4.94 x 2.75 x 1.28 in
Weight (with battery) 10 ounces

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Meter Description
1. Battery Charging Port
2. Download Port
3. Detector Port
4. Tone Mode
5. Power Reading
6. Battery Indicator
7. Data Indicator.
8. Units Indicator
9. Wavelength Indicator
10. SAVE / DOWNLOAD button
11. ON / OFF / Backlight button
12. λ/ AUTO button
13. UNITS / ZERO button
-20.28
1310
4
5
6
7
10
11
8
9
12
13
uW
mW
123

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1. Battery Charging Port - If rechargeable 9-volt batteries are used in the PM200, the
battery charging port is used to re-charge them when used with an approved wall
transformer. NOTE: DO NOT USE BATTERYCHARGING PORT WITH NON-
RECHARGEABLEBATTERIES. THERE IS THE POTENTIAL FOREXPLOSION
AND DAMAGE MAY OCCUR TO THE UNITAND/OR THE USER.
2. Download Port - The download port is used to download stored data into a PC via
the supplied serial cable.
3. Detector Port - The detector port is a fixed 2.5mm universal port, and connects to
ST, SC, or FC connectors equally well without any loss of accuracy. There is no
need to change or maintain expensive adapter caps.
4. Tone Mode - When ‘Hz’ is visible on the display, the PM200 is checking for the
presence of a modulated optical signal. These modulated signals are used to
automatically switch wavelengths when they are sent by an OWL light source with
modulation capability.
5. Power Reading - The power reading displays the level of optical power being
received by the photo detector, and is displayed in either dBm, dB, milliwatts, or
microwatts.
6. Battery Indicator - The battery indicator shows the amount of life is remaining in the
battery. Also, when the battery recharger is in use, the bars in the battery icon are
animated to show that the recharger is active.
7. Data Indicator - This icon shows whether there is data stored in the PM200.
8. Units Indicator - The units indicator shows which units are being currently displayed.
Units are shown in either dBm, dB, uW, or mW.
9. Wavelength Indicator - The wavelength indicator shows the currently selected
wavelength in nanometers (nm).
10. SAVE / DOWNLOAD button - To store a data point, press this button. Hold the
button to down load data points in comma-delimited format. This button can also be
used to erase all stored data if it is held while the meter is being powered ON.
11. ON / OFF / Backlight button - When the unit is off, press this button to power on.
When the unit is on, press this button to toggle the backlight on and off. When the
unit is on, hold this button to power off.
12. λ/ AUTO button - Press this button to change wavelengths. Hold this button to set
the meter in AUTO mode. AUTO mode scans incoming power for modulated optical
signals, and switches wave lengths automatically when a corresponding modulated
signal is received (for use with WaveSource light sources only.)
13. UNITS / ZERO button - Press this button to change display units - either dBm, dB,
uW or mW. Holding this button will set a ZERO reference for the currently selected
wavelength.

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Operation
1.0 Applications
1.1 Precautions
1.1.1 Safety - Caution must be exercised when working with optical equipment.
Most transmission equipment and light sources use light that is invisible to the
human eye. High energy light is potentially dangerous, and can cause serious,
irreparable damage to the eye. Thus, it is recommended to look into the connector
port of a light source or the end of a fiber.
1.1.2 Operational - In order to ensure accurate and reliable readings, it is vitally
important to clean ferrules containing optical fibers and optical connector ports. If
dirt, dust, and oil is allowed to build up inside connector ports, this may scratch the
surface of the photodetector, producing erroneous results. Replace dust caps after
each use.
1.1.3 Operational - In order to ensure accurate and reliable readings, it is vitally
important to clean ferrules containing optical fibers and optical connector ports. If
dirt, dust, and oil is allowed to build up inside connector ports, this may scratch the
surface of the photodetector, producing erroneous results. Replace dust caps after
each use.
1.2 Required Accessories
1.2.1 Cleaning Supplies - It is recommended to clean fiber ferrules before each
insertion with 99% or better isopropyl alcohol and a lint free cloth. A can of
compressed air should be available to dry off the connector after wiping, and to
blow out dust from bulkheads.
1.2.2 Patch Cords - Patch cords may be needed to connect the PM200 to the
system under test. The connector styles on the patch cord must match the type on
the PM200 and the type of the system under test.
1.2.3 Optical Fiber Adapters - Optical fiber adapters are used to connect two
connectorized fibers together, and may be necessary to adapt your patch cords to
the system under test.

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1.3 Typical Applications
PM200 test kits can be used as diagnostic and measurement tools of optical
transmission systems and fiber optic links. These applications can be found in several
industries, including premise, LAN, CATV, and Telco.
Two types of measurements are possible with the PM200 optical power meter: optical
power and optical loss.
1.3.1 Optical Power Measurement - When displaying power in dBm mode, the
PM200 will measure the absolute amount of power being received in the 2.5mm
Universal detector port. Absolute power is shown in dBm (decibels referenced to a
milliwatt), meaning the power being received by the photodetector is compared to 1
milliwatt of optical energy. Optical power measurement is useful for checking the
output power and/or stability of an optical transmission system or stabilized fiber
optic light sources.
1.3.2 Optical Loss Measurement - When displaying power in dB mode, the PM200
can be used to measure the optical power through a fiber optic link relative to an
optical reference point. Setting a reference point is also known as “zeroing” the
meter with a light source. Optical loss measurements are useful for measuring the
attenuation, or loss, of a fiber link. The loss value can then be compared to a pre-
calculated link budget, which is used to determine if the fiber link will operate within
the parameters of the transmission equipment.
The formula for calculating loss in a fiber link is: L = P - P a r
where L is the amount of optical loss in dB, P is the absolute power in dbm, and P
is the reference power in a r dBm.
Optical loss measurements can also be used for fiber optic link certification. Link
certification is a process where optical loss measurements are compared to a link
budget calculated using fiber optic cabling standards.
Data stored in the PM200 can be downloaded into the Reporter certification report
software. Fiber optic links can be certified against one of several popular fiber optic
cabling standards or one of two user configurable standards. Many fiber optic
installation bids are requiring certification reports, which makes the PM200 an
invaluable tool for fiber optic professionals.

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1.4 Optical Power Measurement
a) Connect the PM200 to the
equipment under test (EUT). In the
example below, the EUT is a fiber
optic light source.
b) Power on the EUT, set it to the
desired wavelength, and allow it to
stabilize.
c) Power on the PM200, and set it to
match the wavelength of the EUT.
d) Set the units to dBm. The resultant
reading is the output power. (The
example in Figure 2 shows an
optical output power of -20.58 dBm).
This reading should be within the light
source manufacturer’s specified power
level. If the reading is not within the
specification, clean and check the
connections and take another
measurement.
Figure 2
-20.58
1310 nm
dBm
PM200

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1.5 Optical Loss Measurement (Set Reference)
Two patch cords are required for this procedure - one for the meter side and one for the
light source side.
a) Connect the PM200 to a light source using the first patch cord.
b) Power on the light source and allow it to stabilize according to the manufacturer’s
specifications.
c) Power on the PM200, and set it to match the current wavelength of the light
source.
d) Check to make sure the power level displayed on the PM200 is approximately
equal to the calibrated power level of the light source (see Figure 2 on the previous
page). If it is good, then remove it from the PM200 and light source and set it aside.
This will be the patch cord for the meter side.
e) Connect the other patch cord to the
PM200 and light source as shown in
Figure 3. The example shows a
reference setting procedure for
multimode light sources. Notice the
insertion of a 1/2” mandrel. Mandrels
are used to achieve EMD (Equilibrium
Mode Distribution) when setting the
reference from a multimode light
source. EMD is achieved by wrapping
the reference patch cord around the
mandrel 5-7 times. Single-mode
sources do not require a mandrel.
f) Press the λ/ AUTO button on the
PM200 to set it to the desired
wavelength.
g) Set the light source to the match the
wavelength on the PM200.
h) Press and hold the UNITS / ZERO
button on the PM200. This will set the
reference for the currently selected
wavelength. The display will switch to
show dB units, and should show
approximately 0.00 dB.
If there is a second wavelength to ‘zero’, repeat steps f through h. The indicator LED will
change colors for the second wavelength.
The PM200 is now ‘zeroed’, and is ready to test fiber links.
NOTE: DO NOT REMOVE THE PATCH CORD FROM THE LIGHT SOURCE, AS THIS
WILL MAKE THE OPTICAL REFERENCE INVALID.
0.00
1310
nm
dB
PM200
½” MANDREL
Figure 3

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1.6 Optical Loss Measurement
a) Leaving the patch cord attached to the light
source, remove the patch cord from the PM200
optical power meter.
b) Connect the PM200 and light source to opposite
ends of the link under test.
c) The PM200 will show the amount of loss in the
link (in dB). Figure 4 shows a power level of -2.45
dB. This means that the optical power being
received by the meter is 2.45 dB below the
optical reference, which is the same as saying
there is 2.45 dB of optical loss in the link.
Optical loss measurements are compared to a pre-
calculated link budget. If the optical loss does not
exceed the link budget calculation, the link will
perform as installed within the specifications
shown on the link budget.
-2.45
1310
nm
dB
PM200
PATCH PANELSPATCH PANELS
LINK UNDER TEST
Figure 4