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Troubleshooting
Related Manuals for ILX Lightwave FPM-8200
Summary of Contents for ILX Lightwave FPM-8200
- Page 1 User’s Guide Fiber Optic Power Meter FPM-8200 ILX Lightwave Corporation · P. O. Box 6310 · Bozeman, MT, U.S.A. 59771 · U.S. & Canada: 1-800-459-9459 · International Inquiries: 406-556-2481 · Fax 406-586-9405 · ilx.custhelp.com www.ilxlightwave.com 70034601 January 2010...
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Page 3: Table Of Contents
Default Configuration ........3 FPM-8200... - Page 4 The FPM-8200 Back Panel ........
- Page 5 GPIB Problems ..........69 Optical Measurement Problems ....... . 70 01_10 FPM-8200...
- Page 6 Linewidth Conversions ........79 FPM-8200...
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Page 7: List Of Figures
Figure 2.1 FPM-8200 Front Panel ....... . 5 Figure 2.2 Parameter Setup Front Panel Controls ....7 Figure 2.3 Bar Graph . - Page 8 L I S T O F F I G U R E S FPM-8200...
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Page 9: List Of Tables
Table 1.1 FPM-8200 Fiber Power Meters Specifications ....4 Table 2.1 Gain Range Boundaries ....... . 14 Table 3.1 ANSI/IEEE-488 Terminology . - Page 10 L I S T O F TA B L E S viii FPM-8200...
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Page 11: Safety And Warranty Information
• Prolonged storage under adverse conditions • Failure to perform intended measurements or functions If necessary, return the instrument to ILX Lightwave, or authorized local ILX Lightwave distributor, for service or repair to ensure that safety features are maintained (see the contact information on page xii). -
Page 12: Safety Symbols
Technical specifications including electrical ratings and weight are included within the manual. See the Table of Contents to locate the specifications and other product information. The following classifications are standard across all ILX Lightwave products: • Indoor use only • Ordinary Protection: This product is NOT protected against the harmful ingress of moisture. -
Page 13: Warranty
Returning an Instrument If an instrument is to be shipped to ILX Lightwave for repair or service, be sure to: Obtain a Return Authorization number (RA) from ILX Customer Service. Attach a tag to the instrument identifying the owner and indicating the required service or repair. -
Page 14: Comments, Suggestions, And Problems
WA R R A N T Y Comments, Suggestions, and Problems To ensure that you get the most out of your ILX Lightwave product, we ask that you direct any product operation or service related questions or comments to ILX Lightwave Customer Support. - Page 15 ILX Lightwave instrument: Description of the problem: If ILX Lightwave determines that a return to the factory is necessary, you are issued a Return Authorization (RA) number. Please mark this number on the outside of the shipping box.
- Page 16 WA R R A N T Y FPM-8200...
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Page 17: Introduction And Specifications
NTRODUCTION AND PECIFICATIONS This chapter introduces the FPM-8200 Fiber Optic Power Meter with an overview description. Also included are a list of available accessories to extend the usefulness of your meter, installation instructions, a description of the start-up sequence, and specifications. -
Page 18: Specifications
Customer Service if you need to reconfigure the input voltage range. Tilt-Foot Adjustment The FPM-8200 has front legs that extend to make it easier to view the displays. To use them, rotate the legs downward until they lock into position. -
Page 19: Default Configuration
• RANGE is in MANUAL, lowest gain (10 mA maximum detector current) • SET REF (for dB) = 0.0000 dBm • USER CAL = 1.000 (indicator off) • ZERO is off • RECALL BIN number = 0 01_10 FPM-8200 ... -
Page 20: Table 1.1 Fpm-8200 Fiber Power Meters Specifications
I N T R O D U C T I O N A N D S P E C I F I C A T I O N S C H A P T E R Specifications Table 1.1 FPM-8200 Fiber Power Meters Specifications Wavelength range 800-1600 nm Power range -75 to +1.5 dBm... -
Page 21: Front Panel Operation
RONT ANEL PERATION This chapter describes how to set up and operate your FPM-8200 Fiber Optic Power Meter using the front panel controls. Discussions include installation, front and rear panel familiarization, and general operating procedures. The FPM-8200 Front Panel... -
Page 22: Front Panel Familiarization
LOCAL/ADR 8200 is under remote GPIB control. A flashing REMOTE LED indicates the GPIB controller has put the FPM-8200 in "Local Lockout mode" with the LLO command; in this mode the front panel is completely disabled, including the LOCAL/ADR switch below it. -
Page 23: Parameter Setup Control
Controlsection. If the AUTO indicator is on, pressing UP or DOWN turns the indicator off and steps one gain range. For low level measurements, ILX Lightwave recommends stepping down the range as far as possible for improved resolution. In Manual Gain Range Mode, eight different ranges may be selected by pressing the UP and DOWN keys. -
Page 24: Wavelength
19. Save and Recall Use SAVE and RECALL to store and reuse FPM-8200 setup parameters for future use. These parameters include the gain range, wavelength, display mode, filter mode, and user calibration offset value. Stored setups save time and reduce the chance of setup error for tests that are repeated periodically. -
Page 25: Zero
Note: The best results are obtained by minimizing external influences, because they are rarely stable. For this reason, the FPM-8200 limits the amount of acceptable zero offset. Error E-531 indicates there is too much ambient light for a reliable zeroing. -
Page 26: Filter Control
FR O N T PA N E L O P E R A T I O N C H A P T E R The FPM-8200 Front Panel Filter Control The FILTER control selects measurement averaging and display update rate. -
Page 27: Bar Graph Display
Press LOCAL/ADR and dB at the same time. The USER CAL factor displays for about three seconds. While the USER CAL is displaying, press UP or DOWN to change it. The FPM-8200 saves USER CAL in non-volatile memory, so it retains this value the next time you turn-on the meter. -
Page 28: Linear Power Mode Display
The FPM-8200 Front Panel Linear Power Mode Display Depending on the input power level, the FPM-8200 in linear mode displays power in units nW, µW, or mW. Within these ranges, the decimal point is moved as appropriate for the value: −9... -
Page 29: The Fpm-8200 Back Panel
Three and Four for more information about GPIB control. AC Line Power Input The FPM-8200 meter must be connected to a properly rated AC source in order to operate. Line voltage and frequency limits are defined in Specifications on page 2. -
Page 30: Chassis Ground
The FPM-8200 meter has eight gain ranges. Each range increases gain by 10x over the previous range. The analog output varies 0 V to 10 V representing minimum to maximum current output for that range. -
Page 31: Determining Range
For example, if the primary GPIB address is 1, the front panel displays "-01-". While LOCAL/ADR and AUTO/MAN are depressed together you can change the gain range by pressing UP or DOWN. If the FPM-8200 was in autorange, changing the range this way will change it to manual range mode. -
Page 32: Relating Optical Power To Analog Voltage
"--3--", the instrument is set to range 3. pressed UP three times, the FPM-8200 is on range 3. A voltage reading 5.0V = 50% of scale = 5 µA. Divide current by detector response to get optical power. For example, using 5 µA current, and 0.01193 mA/mW detector response:... -
Page 33: Operating Guidelines
Remote operations are discussed in the next chapter. Warm-up and Environmental Considerations To achieve rated accuracy, let the FPM-8200 warm up for at least 1 hour before use. Operate the meter within the environmental limits specified in Chapter 1. Best accuracy will be available for operation near the calibration temperatures. - Page 34 C H A P T E R Operating Guidelines The best way to measure high power is to use a calibrated attenuator. You can then use USER CAL to set a compensating factor into the FPM-8200 to read it correctly. ...
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Page 35: Understanding The Calibration Certificate
Photodetector Responsivity The FPM-8200 Fiber Optic Meter is a stable low noise current meter with a photodetector. Factory calibration is a process of recording detector current while varying wavelength. The result is a table of detector responses every 10 nanometers, in mA per mW. - Page 36 FR O N T PA N E L O P E R A T I O N C H A P T E R Operating Guidelines FPM-8200...
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Page 37: Remote Operation
• You have a basic knowledge of GPIB programming for instrument control, or other information sources for reference. • You are familiar with the operating controls on the FPM-8200. (Chapter 2) GPIB interface adaptors and support software for standard desktop PCs are available from several manufacturers. -
Page 38: Basic Gpib Concepts
Basic GPIB Concepts The information in this basic concepts discussion is normally not necessary to successfully operate the FPM-8200 through its GPIB interface, because your computer's GPIB controller will usually handle them for you. However this is a useful perspective in understanding GPIB. -
Page 39: Gpib Cable Connections
• REN (remote enable) is set by the controller to place addressed devices into remote or local (front panel) control mode. • SRQ (service request) can be set by any device in the system to request service from the controller. 01_10 FPM-8200 ... -
Page 40: Configuring The Gpib Controller
Please note that overlooking these settings is a common cause of problems. Changing Operation from Local to Remote Sending a command over the GPIB bus addressed to the FPM-8200 automatically puts the instrument in REMOTE mode. In this mode the REMOTE indicator is ON. -
Page 41: Setting The Gpib Address
GPIB address for about 3 seconds. While the GPIB address is displayed, you can change it to any of 31 addresses from "- 00 --" to "- 30 -" by pressing UP or DOWN. Extended GPIB addressing (beyond 30) is not implemented in the FPM- 8200. 01_10 FPM-8200 ... -
Page 42: Command Syntax
(Chapter 4). Upper/lower case does not matter to the FPM-8200, it is just used in this manual to identify optional letters. The optional letters must be in the correct sequence. -
Page 43: Terminators
Many computers terminate with <CR><NL><^END> (Carriage Return - New Line - EOI). This is not a problem, because the FPM-8200 ignores <CR> (Carriage Return) as white space. The FPM-8200 terminates its responses with <CR><NL><^END>, unless you use the TERM command to change it. -
Page 44: Parameters
Command Syntax Parameters Some commands require a parameter. For example, you can set FPM-8200 wavelength response to 1540 nm with the command WAVE 1540, where "1540" is the parameter. The parameter must be separated from the command by at least one space. -
Page 45: Syntax Summary
Mode : dB Mode dB • A leading colon on a command causes the FPM-8200 to begin searching for the next command at the root node. Otherwise (after a semicolon) the FPM-8200 will first search the most recently used node for the command. These examples illustrate this distinction: ENAB:COND?;... -
Page 46: Table 3.2 Invalid Syntax Command Strings
8200 accepts <NL>, or <^END>, or <NL><^END> as a command line terminator. Many computers terminate with <CR> <NL> <^END> (Carriage Return - New Line - EOI). The FPM-8200 ignores <CR> (Carriage Return) as white space. The FPM-8200 terminates its responses with <CR><NL><^END>, unless you use the TERM command to change it. -
Page 47: Internal Registers
Internal Registers Internal registers are used to inform the control program of events and conditions. Concepts The FPM-8200 includes three internal status registers to inform your control program of events and conditions: • Standard event statusó8-bit register required by GPIB standards •... -
Page 48: Register Structure And Contents
GPIB standards. Standard event status indicates the FIRST occurrence, and does not change except when reset. The FPM-8200 starts at power ON with the standard event status register set to all zeros. Querying the Standard Event Status Register resets its contents to zeros. -
Page 49: Event Status Register Pair Contents
Condition Status register pair , except for bit 11. Event status indicates the FIRST occurrence, and does not change except when reset. The FPM-8200 starts at power ON with the event status register set to all zeros. Querying the Event Status Register resets its contents to zeros. -
Page 50: Condition Status Register Pair
Condition Status Register can set bit 3 in the status byte register. Note that this register pair is identical to the Event Status register pair (above), except for bit 11. Conditions reflect the current state of the FPM-8200, and so may change often. Querying the Condition Status Register does NOT change its contents. -
Page 51: Status Byte And Service Request Enable Register Pair
Event Status Not Empty Status Status Status Byte Register STB? Standard Event Condition Service Message Request Event Status (SRQ) SRQ Status Error SRE <nrf> Not used SRE? Service Request Enable Register Figure 3.8 Service Request Enable Register 01_10 FPM-8200 ... -
Page 52: Command Timing
This information should generally not be of concern, except for troubleshooting compatibility issues with a particular GPIB controller. If you are encountering these issues, ILX Lightwave Customer Service can probably help. The FPM-8200 normally responds to multiple queries in a single response output. For example: Mes?; Rad?; Mode?; Err? -
Page 53: Interface Messages
In some of these situations, the FPM-8200 does not fully reset in response to an Interface Clear (IFC) line or a DC1 (device clear) command. To recover from such a condition, it is normally necessary to turn the FPM-8200 power OFF for 10 seconds, then back ON. - Page 54 C H A P T E R Interface Messages The following GPIB remote messages are known to be incompatible with the FPM-8200. Other interface messages, which do not appear in this discussion, may also be incompatible with the FPM-8200. PPR4...
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Page 55: Gpib Command Reference
OMMAND EFERENCE This is a reference guide for GPIB commands that your FPM-8200 responds to, including both common and device dependent commands. A summary list of these commands follows the review of syntax below, for your convenience. The remainder of this chapter is an alphabetical list of command descriptions. Refer to Chapter 3, Remote Operation for additional information about register structure and GPIB programming. -
Page 56: Notes On Syntax
8200 accepts <NL>, or <^END>, or <NL><^END> as a command line terminator. Many computers terminate with <CR> <NL> <^END> (Carriage Return - New Line - EOI). The FPM-8200 ignores <CR> (Carriage Return) as white space. The FPM-8200 terminates its responses with <CR><NL><^END>, unless you use the TERM command to change it. -
Page 57: Gpib Command Reference Summary
Wavelength parameter missing. See Error Messages on page 71 for a list of error codes. GPIB Command Reference Summary Below is a summary reference list of all GPIB commands that the FPM-8200 responds to: Table 4.2 GPIB Summary Reference Command List... - Page 58 *RCL <nrf value> Set reference Set a reference level in dBm REF <nrf value> Reference value? Request the reference level value REF? Responsivity? Request the calibrated detector responsivity data RESP? Reset Recall setup #0, set OCIS and OQIS *RST FPM-8200...
- Page 59 Waits for OPC (operation complete) status *WAI Set wavelength Set wavelength for calibrating detector response WAVE <nrf value> Wavelength? Request wavelength for detector response WAVE? Zero Apply an internal offset ZERO Zero? Request status of zero operation ZERO? 01_10 FPM-8200 ...
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Page 60: Gpib Command Reference
GPIB Command Reference GPIB Command Reference Each GPIB command the FPM-8200 responds to is listed on the following pages in alphabetical order. Each command name is given in correct syntax, is identified as a common or device dependent command, and whether it duplicates a front panel action. - Page 61 The operation−complete flag is false until the delay time elapses. This delay command can be useful for creating delays based on the FPM−8200 clock rather than using the controller’s clock. Examples DELAY 2000—Delay further processing 2 seconds. DELAY 48.2—Delay further processing 48 milliseconds. 01_10 FPM-8200 ...
- Page 62 ENAB:COND 24576—Enables the condition status register so that hardware or software error con− ditions are summarized in the status byte bit 3 (8192 + 16384 = 24576). Enable:cond #H6000˙Same as ENAB:COND 24576, except using hexadecimal numbering. See RADix on page 57. FPM-8200...
- Page 63 ENAB:COND?˙Response 24576 means that hardware or software error conditions will be summarized and reported in the status byte bit 3 (8192 + 16384 = 24576). Enable:cond˙Response #H6000 is the same as 24576, except using hexadecimal numbering. See RADix on page 57. 01_10 FPM-8200 ...
- Page 64 See *PSC. Examples ENAB:EVE 12˙Enables over−range and under−range events to be summarized in the status byte bit 2 (8 + 4 = 12). Enable:event #HC˙Same as ENAB:EVE 12, except using hexadecimal numbering. See RADix on page 57. FPM-8200...
- Page 65 Note 0 = no errors reported. See Error Messages on page 71 for a list of error numbers. Examples ERR?—Response 0 means no errors to report. Errors?—Response 201 means a command parameter value was out of range. 01_10 FPM-8200 ...
- Page 66 See Chapter 3 for more information about register structure. Examples *ESE 128˙Enables power−ON status to be reported in the status byte bit 5. *Ese 60˙Enables errors to be reported in the status byte bit 5 (4 + 8 + 16 + 32 = 60) FPM-8200...
- Page 67 This command allows you to determine which type of error has occurred. See Chapter Three for more information about register structure. Examples *ESR?˙Response 32 means a command error happened. *Esr?˙Response 48 means both execution and command errors happened. (16 + 32 = 48) 01_10 FPM-8200 ...
- Page 68 Examples FILTER SLOW—Updates the display every 5 seconds with the average of 100 measurements. Filter med—Updates the display every 0.5 seconds with the average of 10 measurements. FILT Fast—Turns off measurement averaging. Updates the display every 0.05 seconds. FPM-8200...
- Page 69 Requests the FPM−8200 to identify itself. Response Returns a comma delimited standard format ASCII identification string, from information stored in the FPM−8200 during manufacture. Here is an example of the response: ILX Lightwave,8200,82001234,3.0 Manufacturer Model number Serial number Firmware version number MESsage <ASCII string>...
- Page 70 MODE defines the units of value that will be used for responses to a POW? request. This command has the same effect as selecting the display mode on the front panel. Example Mode:dB˙Measurements are reported in dB (decibels) relative to the reference value. FPM-8200...
- Page 71 EPENDENT Operation Complete? RONT ANEL Action Requests operation complete status. Response ASCII "1" in the FPM−8200 output queue when all pending operations have been completed. Note See Chapter Three for more information about register structure. Example *OPC? 01_10 FPM-8200 ...
- Page 72 1 The enable registers are cleared during power ON. Registers affected: Condition Status Enable: Service Request Enable Event Status Enable: Standard Event Status Enable See Chapter Three for more information on register structure. Example *PSC?˙Request state of power−on status clear flag. FPM-8200...
- Page 73 RADix defines responses, not data entry. To enter data in non−decimal form, use one of the follow− ing prefixes: Hexadecimal Octal Binary Examples RAD DEC—Reset to the factory default decimal radix. Radix HEX; *ESR?—Set hexadecimal radix. Response #H80 means power−on was detected. rad oct—Set octal radix. 01_10 FPM-8200 ...
- Page 74 Response is valid whether the FPM−8200 is in MANUAL or AUTO range mode. Range information is not displayed on the FPM−8200 front panel. Example Range—Response 5 means photodetector current gain is to range 5: 100 nA full scale FPM-8200...
- Page 75 FPM−8200 not to do so. For more information see the discussion of Save and Recall in Chapter Two. Examples *RCL 0—Recall the factory default setup. *RCL 7—Recall setup #7, stored by front panel commands, or by *SAV. 01_10 FPM-8200 ...
- Page 76 Same function as pressing dB and RECALL together on the front panel. Examples REF?˙Response 0 means the reference level is 0 dBm. Ref?˙Response −20 means the reference level is −20 dBm (10 μW). Ref?˙Response 2.79565E−006 means the reference level is 2.79565 μW. Note the change in units. See MODE?. FPM-8200...
- Page 77 GPIB standard <nrf value>, in units: mA / mW Note The information should correspond with that on your latest ILX Lightwave calibration certificate for this meter. If not, contact ILX Lightwave Customer Service to resolve the discrepancy. This information can be useful for understanding the characteristics of your FPM−8200 meter. Notice for example that detector current is much less at shorter wavelengths.
- Page 78 Response is the sum of the enabled bits. See Chapter Three for more information about register structure. Example *SRE?—Response 136 means the service request enable register condition summary and error message bits are enabled (8 + 128 = 136). FPM-8200...
- Page 79 Meanings of the acronyms are historical: CR = Carriage Return (e.g.: a mechanical typewriter) NL = New Line (e.g.: line−feed on a "line printer") ^END = EOI code (End Or Identify) Example Term 4˙Define the message terminator as the IEEE−488 standard: <NL><^END> 01_10 FPM-8200 ...
- Page 80 The TIMER clock is independent of the TIME clock. See TIME? above. The TIMER clock is set to zero at power−ON, so the first response will be the same as a TIME? query. Example Timer?˙Response 0:00:12.07 means 12.07 seconds have elapsed since the last TIMER? query. FPM-8200...
- Page 81 This information is available on the FPM−8200 front panel. Example WAVE?—Response 1552 means FPM−8200 wavelength response is set to 1552 nm. The calibration factor will be interpolated to include 20% of the change in calibration points from 1550 nm to 1560 nm. 01_10 FPM-8200 ...
- Page 82 OPC status. See *OPC?. Example ZERO?˙Response 1 means the zero operation is in progress. Zero?˙Response 0 means the zero process is not in progress. If you just issued a ZERO command, this confirms the process is complete. FPM-8200...
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Page 83: Troubleshooting And Maintenance
Lightwave Customer Service. See page xii for contact information. ILX Lightwave Corporation provides in-house and on-site calibration services for ILX instruments. Most ILX instruments, including the FPM-8200, require yearly calibration to ensure performance to published specifications. ILX factory calibrations employ NIST traceable measurement instrumentation, and our calibration engineers and technicians use automated test equipment to accurately and efficiently capture and record calibration data. -
Page 84: Troubleshooting Guide
Troubleshooting Guide This section lists some common problems and corrective actions. For a comprehensive list of frequently asked questions, see the ILX Lightwave website or contact ILX Lightwave Customer Service (see Comments, Suggestions, and Problems on page xii for contact infomation). -
Page 85: Gpib Problems
Check that no two devices are set to the same GPIB address. • Make sure that there are less than 15 devices on the bus. • Check the configuration of your GPIB controller card. See • Configuring the GPIB Controller on page 24. 01_10 FPM-8200 ... -
Page 86: Optical Measurement Problems
OFF. Line Voltage Setting Line voltage settings are only changed by qualified, factory authorized personnel. Contact ILX Lightwave Customer Service for more information. See Returning an Instrument on page xi for contact information and instructions. FPM-8200... -
Page 87: Error Messages
Error Messages Error Messages Error messages may appear on the FPM-8200 display when error conditions occur that reflect hardware (or zeroing) errors in the instrument. In remote operation, use ERR? to read the current error list. When this is done, a string is returned containing up to 10 of the error messages that are currently in the error message queue. -
Page 88: Table 5.3 Execution Control Errors
Length exceeds maximum Table 5.4 GPIB Errors Error Code Data Type Explanation E−301 Response message Controller failed to read (query error) E−302 Response message Device was addressed to talk but controller failed to read all of the response FPM-8200... -
Page 89: Table 5.5 Operation Errors
Table 5.5 Operation Errors Error Code Explanation E−531 Unable to complete zero operation: input signal too great E−532 Command operation denied: conflicts with zero operation Table 5.6 Hardware Errors Error Code Explanation E−706 Auto calibration cycle aborted 01_10 FPM-8200 ... - Page 90 T R O U B L E S H O O T I N G A N D M A I N T E N A N C E C H A P T E R Error Messages FPM-8200...
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Page 91: Appendix A Conversion Tables
Four tables are provided: dB to percentage, dBm to Watts, wavelength to frequency, and linewidth conversions ( to f). These last two do not apply to power measurements, but you may find them useful for telecommunication applications. FPM-8200 ... -
Page 92: Decibel To Percentage Conversion
= 10 log Power The FPM-8200 makes these relative measurements convenient. Just press dBm/W and dB buttons together to set a reference at the start of your test. Thereafter the front panel shows changes in dB relative to that reference value (Power Decibel (dB) is a convenient way to express large ratios. -
Page 93: Dbm To Watts Conversion
2.00 dBm = 3.98 − dBm = 79.4 − 88 dBm = 1.58 dBm = 3.16 − dBm = 63.1 − 89 dBm = 1.26 dBm = 2.51 − dBm = 50.1 − 90 dBm = 1.00 01_10 FPM-8200 ... -
Page 94: Wavelength To Frequency Conversion
1542.142 199.40 1503.473 189.50 1582.018 194.50 1541.349 199.50 1502.719 189.60 1581.184 194.60 1540.557 199.60 1501.966 189.70 1580.350 194.70 1539.766 199.70 1501.214 189.80 1579.518 194.80 1538.976 199.80 1500.463 189.90 1578.686 194.90 1538.186 199.90 1499.712 −9 THz=terahertz=10 nm=nanometer=10 c=299,792,458 meters/sec FPM-8200... -
Page 95: Linewidth Conversions
37.4 34.9 25.0 17.5 12.5 15.7 11.2 14.0 10.0 12.2 8.73 10.5 7.49 8.73 6.24 6.99 4.99 5.24 3.74 3.49 2.50 1.75 1.25 1.57 1.12 1.40 1.00 1.22 1.05 −9 −12 nm=nanometer=10 meter pm=picometer=10 meter c=299,792,458 meters/sec 01_10 FPM-8200 ... - Page 96 A P P E N D I X FPM-8200...
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