YOKOGAWA FB200 User manual

User’s
Manual
Yokogawa Electric Corporation
FB200
FBG Sensor Monitor
IM 703753-01E
1st Edition

i
IM 703753-01E
1st Edition: April 2004 (YK)
All Rights Reserved, Copyright © 2004 Yokogawa Electric Corporation
Foreword
Thank you for purchasing the FB200C/FB200L FBG Sensor Monitor.
This user’s manual contains useful information about the instrument’s functions and
operating procedures and lists the handling precautions of the FB200C/FB200L. To
ensure correct use, please read this manual thoroughly before operation.
After reading the manual, keep it in a convenient location for quick reference whenever a
question arises during operation.
Note
•The contents of this manual are subject to change without prior notice as a result of
continuing improvements to the instrument’s performance and functions.
•Every effort has been made in the preparation of this manual to ensure the accuracy
of its contents. However, should you have any questions or find any errors, please
contact your nearest YOKOGAWA dealer.
•Copying or reproducing all or any part of the contents of this manual without the
permission of Yokogawa Electric Corporation is strictly prohibited.
• This product’s warranty is limited to its performance and functions. Yokogawa shall
not be responsible for any loss, damage, costs or expenses which may be incurred by
the user in the rare event that the instrument malfunctions. Make sure to consider the
effects of the instrument on your current system and be aware of any remedial
measures that may need to be taken before using the instrument with your system.
Trademarks
• Adobe and Acrobat are trademarks of Adobe Systems incorporated.
• For purposes of this manual, the TM and symbols do not accompany their
respective trademark names or registered trademark names.
• Other company and product names are trademarks or registered trademarks of their
respective companies.
Revisions
•1st edition April, 2004

ii IM 703753-01E
Checking the Contents of the Package
Unpack the box and check the contents before operating the instrument. If some of the
contents are not correct, or if any items are missing or damaged, contact the dealer from
whom you purchased them.
703753
Check that the model name and suffix code given on the name plate on the front panel
match those on your order.
MODEL
NO.
SUFFIX
Made in Japan
MODEL
NO.
SUFFIX
Made in Japan
Model Suffix Code Description
703753 FBG Sensor Monitor
-D1 Standard specifications
-CN1 Optical connector (FC) type
-W1 Wavelength range 1 (1527 to 1567 nm) FB200C C band
-CN2 Wavelength range 2 (1568 to 1607 nm) FB200L L band
Options /IMJ User’s manual (Japanese)
/IME User’s manual (English)
/IM0 No user’s manual
/DSJ Inspection report (Japanese)
/DSE Inspection report (English)
/DS0 No inspection report
•NO. (Instrument Number)
When contacting the dealer from which you purchased the instrument, please give
them the instrument number.

iii
IM 703753-01E
Safety Precautions
The following general safety precautions must be observed during all phases of
operation. If the instrument is used in a manner not specified in this manual, the
protection provided by the instrument may be impaired. Yokogawa Electric Corporation
assumes no liability for the customer’s failure to comply with these requirements.
The following symbols are used on this instrument.
Danger. Refer to the user’s manual. This symbol appears on dangerous locations on
the instrument which require special instructions for proper handling or use. The same
symbol appears in the corresponding place in the manual to identify those instructions.
Make sure to observe with the precautions below. Not complying might result in
injury or death.
WARNING
•Power supply
Ensure that the source voltage matches the voltage of the power
supply before supplying the power. Use a power supply that conforms
to the IEC60950 standard.
•Connect the Protective Grounding Terminal
If you are using the 703781 Power Supply Unit with the FB200C/
FB200L, be sure to employ protective earth ground by connecting a
power cord with a three-prong plug (with an earth pin) to a properly
grounded three-pin outlet.
•Do Not Operate with Defective Protective Grounding or Fuse
Do not operate the instrument when the protective grounding or fuse of
the instrument or the connected device might be defective. Make sure
to check them before operation.
•Do Not Look at the Laser Light
Do not look at the laser’s direct light, reflected light from a mirror, or
indirect light without the proper protective eyewear. In addition, avoid
being exposed to the laser light. It can cause blindness or damage to
the eye.
When using a laser light source, always check the precautions given in
the user’s manual for the laser and handle it with extra care.
•Do Not Operate in an Explosive Atmosphere
Do not operate the instrument in the presence of flammable liquids or
vapors. Operation in such environments constitutes a safety hazard.
•Do Not Remove Covers
The cover should be removed by ANDO’s qualified personnel only. If
you remove the cover, the instrument may break or its performance
may deteriorate.

iv IM 703753-01E
How to Use This Manual
Structure of This Manual
This user’s manual consists of the following sections.
Chapter Title
Description
1Explanation of Functions
Describes the measurement principles and the functions of the instrument. Operational
details are not given in this chapter. However, reading this chapter will help you understand
the operating procedures given in the chapters that follow.
2 Installation Procedure
Describes the handling precautions, connection procedures, installation conditions, and
operating environment.
3Operating Procedure
Describes how to set measurement conditions and how to operate the instrument including
topics such as how to set the mode switch, how to use the control commands, the output
format, and how to control the instrument from your PC. For errors that occur during
measurements, see the troubleshooting and maintenance sections in the next chapter
4Troubleshooting and Maintenance
Describes the probable causes of errors and how to resolve them. Describes maintenance
work.
An error code list of measurement signals are also provided.
5Specifications
Lists the specifications of the instrument, the operating environment, and other information in
tables.
6Sample Program
Provides a basic program example used to determine two peaks.
Index and Terminology
Conventions Used in This Manual
•Unit
k: Denotes 1000. Example: 9.6 kbps
•Safety Markings
The following marking is used in this manual.
Improper handling or use can lead to injury to the user or damage to
the instrument.
This symbol appears on the instrument to indicate
that the user must refer to the user’s manual for special instructions.
The same symbol appears in the corresponding place in the user’s
manual to identify those instructions. In the manual, the symbol is
used in conjunction with the word “WARNING” or “CAUTION.”
WARNING Calls attention to actions or conditions that could cause serious or
fatal injury to the user, and precautions that can be taken to prevent
such occurrences.
CAUTION Calls attentions to actions or conditions that could cause light injury
to the user or damage to the instrument or user’s data, and
precautions that can be taken to prevent such occurrences.
Note
Calls attention to informor proper operation of the instrument.

v
IM 703753-01E
1
2
3
4
5
6
Index
Contents
Checking the Contents of the Package ...........................................................................................ii
Safety Precautions ......................................................................................................................... iii
How to Use This Manual ................................................................................................................ iv
Chapter 1 Explanation of Functions
1.1 Block Diagram and Configuration Diagram ...................................................................... 1-1
1.2 Measurement Method ...................................................................................................... 1-2
1.3 Names and Functions of Parts ......................................................................................... 1-4
Chapter 2 Installation Procedure
2.1 Operating Precautions ..................................................................................................... 2-1
2.2 Connecting the Interface Connector ................................................................................ 2-2
2.3 Installing the Instrument ................................................................................................... 2-3
Chapter 3 Operating Procedure
3.1 Setting the Mode Switch .................................................................................................. 3-1
3.2 Commands ....................................................................................................................... 3-2
3.3 Output Format .................................................................................................................. 3-6
3.4 Using the FB200C/FB200L through a PC ........................................................................ 3-7
Chapter 4 Troubleshooting and Maintenance
4.1 Troubleshooting ............................................................................................................... 4-1
4.2 Error Codes ...................................................................................................................... 4-2
4.3 Maintenance .................................................................................................................... 4-4
Chapter 5 Specifications
5.1 Basic Specifications .........................................................................................................5-1
5.2 General Specifications ..................................................................................................... 5-2
5.3 Environmental Conditions ................................................................................................ 5-3
5.4 External Dimensions ........................................................................................................ 5-4
Chapter 6 Sample Program
6.1 Terminal Mode Settings ................................................................................................... 6-1
6.2 Program Setup ................................................................................................................. 6-2
Index and Terminology
Index .................................................................................................................................. Index-1
Terminology .......................................................................................................................... Index-3

1-1
IM 703753-01E
Explanation of Functions
1
Chapter 1 Explanation of Functions
1.1 Block Diagram and Configuration Diagram
The block diagram of the optical system is shown below. The optical system employs a
polychromator system consisting of a fixed grating and a photodiode array (PDA sensor).
Because the reflection spectrum of FBG can be detected using an optical system with its fixed
elements (component parts), it is ideal for applications that demand high reliability.
The principles of spectroscopy are described below. The light input from the FC connector is
collimated by the lenses and hits the fixed grating. Here the reflection spectrum of FBG is
dispersed and divided into each wavelength of light. Then, the light is focused on the
photodiode array by the lens. This focal point is detected by scanning the InGaAs photodiode
array (consisting of 640 photodiode elements). The optical system is fixed in place (welded if
necessary) to endure vibration and shock, and to minimize deterioration with age.
Photodiode array
Mirror
Shutter
Fixed
grating
Signal processing
and
communication section
Input fiber
(FC/PC connector)
Depolarizer
The configuration diagram is shown below. The reflection spectrum of FBG that is detected
by the optical system (shown above) is I/V converted, A/D converted, and processed using a
digital signal processor (DSP) to derive the center wavelength and optical power level of
each reflection spectrum of FBG. In addition, in order to determine the optical power level in
a stable manner, the photodiode array is maintained at a constant temperature.
Shutter motor
Motor Driver To Host
RS-422
DSP
DSP controller
Wavelength computation,
power computation, etc.
Filter
A/D
Up to
16 bits
Photodiode array
module
Temperature
control
Photodiode array
module timing
control
Serial
interface
Thermoelectric
cooler
Photodiode
array
(640 cells)
Temperature
sensor
I/V
AMP
1
10

1-2 IM 703753-01E
1.2 Measurement Method
In the measurement of strain, temperature, and other items using the FBG sensor, strain,
temperature, and other items can be derived by measuring the reflection spectrum from
the grating area that forms in the optical fiber. The FBG wavelength monitor is a useful
instrument for measuring the wavelength.
This section describes how the optical wavelength and optical power level are measured
using the FBG Sensor Monitor. The center wavelength and its optical power level is
calculated from the power distribution of the optical signal obtained by multiple PD
elements and the wavelength that is pre-assigned to each PD element.
You can set appropriate measurement conditions by changing parameters such as the
average count, threshold value, and offset value. Furthermore, the optical wavelength
and optical power level are calibrated before the instrument is shipped from the factory.
Commands are also provided to compensate the results of these measurements if such
compensation is necessary after the instrument is installed in the system.
Computed result of center wavelength
Reflection spectrum of FBG
Optical wavelength
Device output
Optical power

1-3
IM 703753-01E
Explanation of Functions
1
Because the FB200C/FB200L uses a polychromator system with no moving parts, high-
speed stable measurement is possible.
The basic measurement sequence is shown below (examples for –5 dBm and –15 dBm
ranges).
•When Averaging Is Not Performed
The measurement interval is determined by the selected interval. (The default value
is 10 ms.)
However, if the wavelength calculation and processing take longer than the
measurement interval, the resultant data are output when they are ready. (Example
when the number of FBG spectra is 10 and the baud rate is 921.6 kbps)
PDA sensor start
trigger
Wavelength
computation, etc.
Approx.
7 ms
Data transmission/
communication
Scan the PDA sensor
Retrieve the A/D data
Approx.
7 ms
Approx.
2 ms
Data acquisition
time
Specified interval
Reference
•When Averaging n Times
If the wavelength calculation and processing take longer than the measurement
interval, the resultant data are output when they are ready.
PDA sensor start
trigger
Wavelength
computation, etc.
Approx. 7 ms
Data transmission/
communication
Scan the PDA sensor
Retrieve the A/D data
Approx.
7 ms
Approx.
2 ms
1st
time
2nd
time
nth
time
1st
time
2nd
time
nth
time
1st
time
2nd
time
nth
time
Reference
1.2 Measurement Method

1-4 IM 703753-01E
1.3 Names and Functions of Parts
The figure below shows the outline and the arrangement of parts such as the optical
input, interface connector, and mode switch.
•Mode Switch
The mode switch is located inside the side panel cover. You can set the operation
mode, transfer rate, and other parameters by using these switches.
•Interface Connector
The interface connector consists of the communication interface and power supply
interface. The communication interface is the RS-422.
•Optical Input
The fiber light is applied here. The optical connector is of an FC type (standard), and
the fiber supports the SMF (Single Mode Fiber).
•Holes for Attachment Screws
These holes are used to attach the FB200C/FB200L in the system.
Mode switch Optical input
Interface connector
Holes for M3 attachment screws (6 locations)
87654321
ON
Mode switch

2-1
IM 703753-01E
Installation Procedure
2
Chapter 2 Installation Procedure
2.1 Operating Precautions
CAUTION
The photodiode array module can be damaged, if a light greater than or
equal to 10 mW per wavelength or 100 mW total power is incident.
Never apply power that exceeds the limits described above.
• The optical system on this instrument is precisely adjusted and fixed. Use the
instrument under prescribed environmental conditions. Never use the instrument
under conditions in which condensation may occur.
•Use a power supply that generates a voltage within the specified range. In addition,
use a power supply that complies with the IEC60950 standard.
•The FB200C/FB200L’s case is connected to the circuit ground. To achieve proper
operation in a noisy environment, connect the case to a frame ground with the same
electric potential as the circuit ground.
•Do not turn ON the power immediately after turning the power OFF. Wait until the
supply voltage falls below 1 V. If you are using the 703781 Power Supply Unit, wait 5
seconds before turning the power ON.
• The instrument must be warmed up for at least 30 minutes in order for it to exert the
full performance given in the specifications.
• Do not connect objects other than those that are specified for the connector of the
instrument. If you do, the instrument may malfunction.
•Abnormal operation in the electrical circuit or contamination on the surface of the
optical sensor (leads to degrading of sensitivity) may occur, if the instrument is moved
to another place where the ambient temperature is higher or if the temperature
changes rapidly. Use the instrument so that water droplets do not adhere to it.
•Do not use the instrument in a dusty place. Always attach the accessory cap after use.
• Remove dusts that adhere to the optical sensor and optical connector sections using
air duster or other similar tools. If you must wipe the dust or stains, use a cotton swab
moistened with ethanol. Do not use objects that may scratch the sensor section such
as industrial gauze.
•Do not apply optical power that exceeds the maximum optical input power of the
instrument.
•Do not use the instrument near objects that emit strong radio waves and magnetic
fields. This can lead to erroneous operation.
•Ambient Temperature and Humidity
Ambient temperature: 0 to 60°C
Ambient humidity: 5 to 85% RH, no condensation.
•Handling the Optical Fiber Cable
•Do not pull or bend the optical fiber cable.
• Before making a connection, wipe the end face of the optical fiber using a cotton
swab (or a similar object) moistened with ethanol and wait for the ethanol to dry.
•Be sure not to damage the end face of the optical fiber.
(If damage is present at the end face of the optical fiber, a gap is created at the
connection. This gap causes laser light interference and output fluctuations.)
•Securely insert the optical connector at the appropriate position according to its shape.

2-2 IM 703753-01E
2.2 Connecting the Interface Connector
•Check the pin assignments of the interface connector and the input line connection,
before connecting the connector. The pin assignments and details of the interface
connector are given in the table below.
Make sure to connect the case to the device’s frame ground. This will prevent erroneous
operation due to noise. Use a power supply that complies with the IEC60950 standard.
Pin No. Signal Name Signal Description Note IN/OUT
1VCC 5-V digital power input IN
2VCC 5-V digital power input IN
3GND GND
4GND GND
5GND GND
6GND GND
7VCC 5-V digital power input IN
8VCC 5-V digital power input IN
9GND GND
10 NC No connection
11 PVCC 5 V for the thermal cooler IN
12 PVCC 5 V for the thermal cooler IN
13 PGND GND for the thermal cooler
14 PGND GND for the thermal cooler
15 TCLK+ Transmit clock (RS422)+ baud rate ×16* OUT
16 TCLK- Transmit clock (RS422)- baud rate ×16* OUT
17 RCLK+ Receive clock (RS422)+ baud rate ×16* IN
18 RCLK- Receive clock (RS422)- baud rate ×16* IN
19 TXD+ Transmit data (RS422)+ OUT
20 TXD- Transmit data (RS422)- OUT
21 RXD+ Received data (RS422)+ IN
22 RXD- Received data (RS422)- IN
23 RESET Reset pin Low input for reset IN
TTL or CMOS 5 V input
24 GND
25 WDG Low during Watch Dog error Open collector OUT
26 GND
27 TMP Low during temperature Open collector OUT
control error
28 BUSY Low during measurement Open collector OUT
29 WARMUP Low during warm-up Open collector OUT
30 ERROR Low during other errors Open collector OUT
*: The clock frequency is equal to 16 times the baud rate.
Note 1: The connector that is used is the FCN-705Q030-AU/M connector made by Fujitsu
Components Limited. Use a plug that supports this connector.
The causes of other errors include communication error, PDA sensor alarm, DSP error,
ROM/RAM error, and temperature alarm. For communication errors and RDA sensor
alarms, the other errors signal is cleared after receiving the REA_7 response.
Note 2: If a hardware reset is executed, you must wait approximately 18 s before issuing the
measurement command.
•Always clean the end face of the optical fiber before connecting it.
Example: Rub the end face of the optical fiber using a cotton swab moistened with
ethanol and blow off the ethanol with dry air. You can use other equivalent
methods to clean the ends of the fiber.
•Take special care not to damage the end face of the optical fiber when connecting it. As with
the presence of dust, scratches on the end face of the optical fiber will have adverse effects on
the optical power level measurements. When connecting the optical fiber, connect it securely.

2-3
IM 703753-01E
Installation Procedure
2
2.3 Installing the Instrument
The operating environment of the FB200C/FB200L is described below. Always operate
the instrument within the range specified. The figure below shows the temperature and
humidity range.
To maintain the adequate performance over a long period, apply as little vibration and
shock as possible even if they are within the specifications.
CAUTION
Applying a voltage exceeding the maximum rating (–0.3 to +6.5 V) to the power supply
will damage the circuit. Do not apply excessive voltage to the power supply.
•Ambient Temperature and Humidity
Ambient temperature: 0 to 60°C
Ambient humidity: 5 to 85% RH, no condensation.
Note
To obtain highly accurate measurements, operate the instrument in the 23 ±5°C temperature
range.
Condensation may occur if the instrument is moved to another place where the ambient
temperature is higher, or if the temperature changes rapidly. In such cases, allow the
instrument adjust to the new environment for at least one hour before using the instrument.
•Do not install the instrument in the following places:
In direct sunlight or near heat sources.
Where an excessive amount of soot, steam, dust, or corrosive gas is present.
Near high voltage equipment or power lines.
Where the level of mechanical vibration is high.
On an unstable surface.
-5
010203040506070809010
0
0
5
10
15
20
25
30
35
40
45
50
55
60
Operation humidity range
Relative humidity (%)
Temperature [°C]

2-4 IM 703753-01E
• Installation Procedure
Attach the FB200C/FB200L using the six holes for attachment screws shown in the
figure below. When fastening the FB200C/FB200L in place, be sure that the
attachment screws do not go deeper than 5 mm from the surface of the case.
130
98
19612
146 12
Holes for M3 attachment screws (6 locations)
5mm or less
FB200C/FB200L case
Panel for attaching the FB200C/FB200L Attachment screw (M3)
2.3 Installing the Instrument

3-1
IM 703753-01E
Operating Procedure
3
Chapter 3 Operating Procedure
3.1 Setting the Mode Switch
The FB200C/FB200L is designed to be integrated into an FBG sensing system device. It
has various device settings and commands to be used with the system. This chapter
describes the setup and commands for the FBG sensing system device.
In addition, the FB200C/FB200L can be connected to your PC via the RS-232C interface
by using the 703781 Power Supply Unit that is sold separately.
The mode switch (see page 1-4) can be changed to switch the synchronization clock and
the baud rate. The table below shows the mode switch settings and functions.
Disconnect the power supply when changing the mode switch.
•Method of Detecting the Number of Wavelengths and Its Limitation
The FB200C/FB200L detects reflection spectra within the measurement conditions
starting from the reflection spectrum with the highest optical power level up to the limit
of the number of FBG reflection spectra. FBG reflection spectra that exceeds the limit
are not detected.
•Selecting the Baud Rate
Six baud rate settings are available. By factor default, the baud rate is set to 115.2
kbps.
Signal
Name
9.6k
bps
SW1__8
SW1__7
SW1__6
SW1__5
SW1__4
SW1__3
SW1__2
SW1__1
38.4k
bps
115.2k
bps
307.2k
bps
460.8k
bps
921.6k
bps
9.6k
bps
nonparity
Signal
Baud rate selection
Baud rate selection
Baud rate selection
Internal CLK = OFF
External CLK = ON
System reserved
System reserved
System reserved
System reserved
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
OFF
Default: OFF Internal CLK
ON (fixed)
ON (fixed)
OFF (fixed)
OFF (fixed)
ON
ON
OFF
OFF
OFF
ON
ON
OFF
ON
ON
ON
ON
Pin
No
8
7
6
5
4
3
2
1
Note: Serial communication: Fixed to 8-bit data, 1 stop bit, even parity, start-stop
synchronization, full duplex, and Xon/Xoff flow control. Do not change the mode switch
during operation.

3-2 IM 703753-01E
3.2 Commands
The FB200C/FB200L has various commands and response statuses. By setting the
measurement conditions, appropriate signals can be measured. Statuses can be
received to check the instrument’s conditions.
The transmission and reception of commands and statuses are executed via the RS-422
interface.
The descriptions of the control commands and statuses are given below.
Command Name Command Control Description
Continuous BPR Starts the measurement, repeats the measurement for the
measurement start specified average count, and outputs the center wavelength
and peak power. The operation repeats at the specified
interval. The peak power is converted to RBW 0.1 nm.
Single measurement BPM Starts the measurement, repeats the measurement for the
specified average count, and outputs the center wavelength
and peak power. The output format is the same as with the
BPR command.
Measurement stop STO If the measurement is stopped in the middle of the averaging
operation, the center wavelength and peak power are derived
from the data up to that point. Then, the center wavelength
and peak power are output, and the measurement is stopped.
Set the average count AVE_nn nn: "01" to "99"
Returns OK:AVE_nn when the process is complete.
The default value is 1.
Query AVE? Returns AVE_nn or AVI_nne.
Set the average count AVI_nne nne: "101" to "503"
(100 times or more) nne="203": 20×103= 20000 times
Each average operation takes approximately 7 seconds.
The default value is 101 (100 times).
Query AVI? Returns AVInne or AVE_nn.
Zero calibration ZER Closes the shutter and performs zero measurement for
each range. The response time is approximately 13 seconds.
Returns OK:ZER when the process is complete.
The dark current default is the data that was measured
before factory shipment.
Set the alarm ZTH_nnn Sets the threshold level for the PDA alarm.
threshold level nnn="050": 50nW
The selectable range is from 000 to 999 nW.
Returns OK:ZTH_nnn when the process is complete.
The default value is 240 nW.
Set the offset OFF_nnnn Sets the wavelength compensation value.
nnnn="±012": ±0.12 nm
The selectable range is from –9.99 to +9.99 nm.
Returns OK:OFF_nnnn when the process is complete.
The default value is 0.
Query OFF? Returns OFF_nnnn.
Set the threshold level BTH_nnnnn, Sets the threshold level for detecting the reflection spectrum
nnnnn,nnnnn, of FBG for each optical power range.
nnnnn nnnnn="-2234": –22.34 dBm
Returns OK:BTH_nnnnn,nnnnn,nnnnn,nnnnn when the
process is complete.
The default values and selectable ranges are as follows:
Optical Power Default Selectable Range
Range Value
–5 dBm –30 dBm –10.00 to –45.00 dBm
–15 dBm –40 dBm –20.00 to –55.00 dBm
–25 dBm –50 dBm –30.00 to –65.00 dBm
–35 dBm –60 dBm –40.00 to –75.00 dBm
Query BTH? Returns BTH_nnnnn,nnnnn,nnnnn,nnnnn.

3-3
IM 703753-01E
Operating Procedure
3
Command Name Command Control Description
Set the threshold RBT_nnnnn Sets the threshold level for computation in the current
level for the current measurement range.
range nnnnn="-2234": -22.34 dBm
Returns OK:RBT_nnnnn when the process is complete.
Query RBT? Returns RBT_nnnnn.
Set the range RNG_nnn Sets the measurement optical power range.
nnn="-05": –5 dBm, nnn="-15": –15 dBm,
nnn="-25": –25 dBm, nnn="-35": –35 dBm
Returns OK:RNG_nnn when the process is complete.
The default value is –5 dBm range.
Upper limit: –3.5 dBm or more at –5 dBm range
:–13.5 dBm or more at –15 dBm range
:–23.5 dBm or more at –25 dBm range
:–33.5 dBm or more at –35 dBm range
Query RNG? Returns OVER, if the peak power value exceeds the upper
limit.
Set the optical power UPR_nnn, Sets and saves the optical power compensation value for
compensation data nnn, nnn, each range.
nnn nnn="112": ×1.12
The selectable range is from ×0.00 to ×9.99.
Returns OK:UPR_nnn,nnn,nnn,nnn when the process is
complete.
The default value is ×1.
Query UPR? Returns UPR_nnn,nnn,nnn,nnn.
Set the interval TIM_nnn Sets the measurement interval in milliseconds.
nnn="020": 20 ms intervals
Returns OK:TIM_nnn when the process is complete.
Measurement repeat interval
If the measurement interval cannot be kept such as when
the average count is large, the specified interval is ignored.
The default value is 10 ms.
The selectable range is 10 to 990 ms (in 10 ms steps).
Query TIM? Returns TIM_nnn or TIS_nnn.
Set the interval TIS_nnn Sets the measurement interval in unit of seconds.
(1 s or more) nnn="060": 60 s intervals
Returns OK:TIS_nnn when the process is complete.
The default value is 1 s.
The selectable range is 1 to 360 s (in 1-s steps).
Query TIS? Returns TIS_nnn or TIM_nnn.
Set the number of PNM_nnn Sets the maximum number of output waves.
output FBG nnn="040":Set the maximum output wave number to 40.
(spectrum) data The selectable range is 000 to 100 waveforms.
Returns OK: PNM_nnn when the process is complete.
The default value is 40 waveforms.
Set the bandwidth MBW_nnnn Sets the total width of the wavelengths used in the center
wavelength computation (see the figure on the page 3-5).
nnnn="0700": 700 pm
Returns OK:MBW_nnnn when the process is complete.
The default values and selectable ranges are as follows:
Default value 800 pm
Selectable range 200 pm to 2.000 nm
Query MBW? Returns MBW_nnnn.
Set the peak condition MBL_nnn Sets the minimum value of the maximum power difference
in the computation bandwidth used to detect peaks (see the
figure on the page 3-5).
nnn="400": 4.00 dB
Returns OK:MBL_nnn when the process is complete.
The default values and selectable ranges are as follows:
Default value 4.00 dB
Selectable range 0.00 dB to 9.99 dB
Query MBL? Returns MBL_nnn.
3.2 Commands

3-4 IM 703753-01E
Command Name Command Control Description
Set the wavelength WLT_nnnnn, Sets the output wavelength range.
range nnnnn nnnnn,nnnnn="15320, 15670":
Outputs the data corresponding to the peak that is detected
within the wavelength range between 15320.0 nm and
15670.0 nm.
The selectable range is from 0.0 to 9999.9 nm. However,
the 2nd parameter must be larger than the 1st parameter.
The default value is 00000, 00000. If set to default, the
output wavelength range is set to the measurement
wavelength range defined by the specifications.
Returns OK: WLT_nnnnn,nnnnn when the process is
complete.
Initialize settings RES Initializes the settings to default values.
Returns OK:RES when the process is complete.
Error status CHE Clears all error statuses and alarm output.
Returns OK:CHE when the process is complete.
STATUS SRQ Returns the operation status.
REQUEST n=1 :The response format is STA_n.
n=2: Measuring
Warming up (synchronized with the warm up output,
30 to 40 seconds after reset, only SRQ is accepted)
n=3:Zero calibrating
n=4:Idle
READ REA_n Returns the contents of register A.
REGISTER_A n=1:Retransmitting measured data
n=2:Returns the average count. AVE_nn
n=3: Zero calibration value. Returns the number of
elements exceeding the threshold level and the dark
current value and the wavelength of the element
exceeding the threshold level.
ZER_n,nnn,nnnnnn,....
n:Number of elements exceeding the threshold
level. 0 signifies that there are no elements
that exceed the threshold level. Data for up
to 10 elements is output even if more than
10 elements exceed the threshold.
nnn: Dark current value nW
nnnnnn:Wavelength nm
Data assigned to the element + wavelength offset
Approximate conversion of the dark current: 1 nA = 5 nW
n=4:Returns the offset value. OFF_±nnn
n=7:Returns the contents of the error. ERR_n,n,n,....
n=8:Returns the measurement interval. TIM_nnn
READ REB_n Returns the contents of register B.
REGISTER_B n=1:Returns the specified output data. OUT_n
n=5:Returns the zero threshold level. ZTH_nnn
n=6:Returns the current range value. RNG_nnn
n=8:Returns the maximum number of output waveforms.
PNM_nnn
n=9:Returns the output wavelength limit. WLT_nnnnn,nnnnn
READ REC_n Returns the contents of register C.
REGISTER_C n=2:Returns the user-defined optical power compensation
value. UPR_nnn,nnn,nnn,nnn
n=9:Returns the threshold value of each optical power
range.
BTH_nnnnn,nnnnn,nnnnn,nnnnn,nnnnn
Version information VER Query command for firmware version information
FBG SENSOR Monitor FB200X TMS320C32 Module
Version X.XX Jan 01 2003 hh:mm:ss (When Link is 2003/
01/01)
FB200X: Current variations are FB200C and FB200L.
Note: Since the number of digits is fixed for parameters, fill 0s in front of the values to match the
number of digits as necessary.
3.2 Commands

3-5
IM 703753-01E
Operating Procedure
3
Optical wavelength
Optical power
Photodiode array element
Computation bandwidth
Peak condition
Set the computation bandwidth to a value that covers the ends of the spectrum.
However, do not let it cover the adjacent spectrum.
(The guide line is approximately twice the Full Width Half Maximum.)
3.2 Commands

3-6 IM 703753-01E
3.3 Output Format
The FB200C/FB200L outputs the number of waveforms, center wavelengths, and optical
power levels of the reflection spectrum of FBG.
The output data format is shown below.
BPM nnn,nnnnnnn±nnnn,nnnnnnn±nnnn,nnnnnnn±nnnn,-----CRLF
Optical power level of the 1st peak
2nd center wavelength and optical power level
1st center wavelength
The number of FBG reflection spectra detected
Example If the output is BPM_002,1550334-1624,1557987-1576,
The number of detected FBG reflection spectra is 2.
The first center wavelength and power level are 1550.334 nm and –16.24
dBm, respectively.
The second center wavelength and power level are 1557.987 nm and –15.76
dBm, respectively.
The detected FBGs are output in order from the shortest wavelength.
Response Data Format Description
Response format BPM_nnn, followed by the nnn="040": Transmit values of 40 waveforms: For
measured values of each the number of detected waveforms
peak for nnn waveforms. Example:
BPM_nnn,nnnnnnn±nnnn,nnnnnnn±nnnn,
The order is wavelength followed by power.
nnnnnnn±nnnn,--------CRLF
Outputs up to 40 waveforms starting from the
spectrum with the largest power.
Response format nnnnnnn±nnnn, Wavelength and power level
of a single peak
Wavelength nnnnnnn nnnnnnn="1553210": 1553.210 nm
Optical power ±nnnn ±nnnn="-1234": –12.34 dBm
level When the power is over the range:
+OVER is returned in its place.