Wilcom MODEL T312B Optical Attenuation Test Set Operating Instructions T312B Optical Attentuation Test Set Operating Instructions 804-702-009 August 2007 Copyright (c) 2007 Wilcom All Rights reserved Wilcom reserves the right to make changes to the material contained herein without notice and shall not be liable for errors contained herein or for incidental, consequential damage in connection with the furnishing, performance or use of this material. This document may not be copied or duplicated in part or in whole for any purpose without the express written permission of Wilcom. i Table of Contents Page General..................................................................................1 Introduction..........................................................................2 Description..........................................................................2 Connector Options..............................................................2 Bare Fiber Adapter..............................................................2 Wavelength Options........................................................... 2 Mode Filter......................................................................... 2 Test Sets vs Connectors and Reference Cables...................3 Specifications........................................................................4 Panel Controls and Connections.........................................7 General................................................................................7 Display................................................................................ 7 Function Related...................................................................7 Power Related......................................................................8 Operating Instructions.........................................................9 Maintenance.........................................................................15 Battery Replacement...........................................................15 Cleaning..............................................................................15 Fuse Replacement...............................................................15 Service and Repair...............................................................16 Warranty...............................................................................17 Figures 1. T312B Test Set..................................................................5 2. Loop Around Testing.........................................................8 3. Testing Installed Cable.......................................................13 ii General The information contained in this manual will cover several versions of the Model T312B, Where differences occur, the applicable model will be distinguished by the suffix -03, -05, -17, or other means of identification as necessary. NOTE: T312B-17 is a universal set and adapts to various connector types. Accessory connectors and reference cables are ordered separately for this set. See price list. Description The Model T312B Optical Attenuation Test Set is a ruggedized, compact, lightweight, portable field tester designed to measure optical power level or attenuation of fiber optic systems. A 3 1/2 digit LCD display reads out the absolute power level from +3 dBm to -65 dBm or the optical attenuation of a cable over a range of 45 dB, The front panel ATTEN 0-ADJ and a reference cable permit direct reading of attenuation on the LCD display. The PULL ON switch applies power for unit operation. The BATT CHG indicator verifies that the battery is charging. The TRANSMIT switch is a 3-position toggle switch, TRANSMIT, OFF, TRANSMIT (MOM). The MOM (momentary) position is suggested for battery operation to maximize time between battery charge. The receive switch is a two-position toggle switch, ATTEN dB/LEVEL dBm. This switch allows the LCD to display cable attenuation or absolute power level measured at the RECEIVE port. TRANSMIT and RECEIVE ports are provided with dust caps to protect the lenses, The set is equipped with rechargeable Ni-Cad batteries for field use which can be charged from 115/230 Volts, 50-60 Hz (factory voltage option). 1 Introduction The set is supplied with a protective cover which stores the power cable and reference fiber. To prevent battery drain, the power is automatically shut off when the cover is closed. The cover is easily removed when the set is in use. Connector Options The T312B is designed to mate with connectorized field installed cables. A series of dash numbers identify the connector type supplied. Example: (T312B-03, Amphenol Connector with 50/125 pm fiber. This means that the TRANSMIT and RECEIVE port receptacles and the 1 meter length of reference cable terminated with Amphenol 906 series connectors). An in-line bushing to mate with the system cable under test is also supplied. Bare Fiber Adapter When installing fiber optic cable, the unit is used to measure spliced lengths of bare fiber. The T312B-03 (Amphenol) may be provided with a bare fiber adapter for the TRANSMIT and or the RECEIVE port. The T312B-17 also may be used with the bare fiber adapter when using 3005 adapter caps. Otheradapters can be made available on special order. Wavelength Options The standard TRANSMIT wavelength for the T312B is 840 nm. For other wavelengths, consult factory. Mode Filter The use of a one meter reference cable to measure attenuation may give a pessimistic loss reading of up to 0.5 dB. The reason is the output from the reference cable includes cladding and lossy modes which are not present in longer lengths of fiber. The ideal condition 2 Introduction (cont.) would be an output from the reference fiber with the modes in equilibrium. To simulate this condilion, a mode filter can be provided to eliminate the lossy modes. Consult factory on availability of mode filter for individual sets. Test Sets vs Connectors and Reference Cables T312B-03 Amphenol Connector 906 Series Reference Cable Included T312B-05 W.E. L1A1 -A Connector Reference Cable Included T312B-17 Universal Connector accommodates all 3000 Series accessory connectors. (The accessory connectors and reference cables are not included consult the Wilcom price list. 3 Specifications Transmit Section Source: LED; 850 nm +I 0 nm wavelength; spectral bandwidth of +/-40 nm. (other sources by special order) Level: Adjustable from approx. -22 dBm to -15 dBm into 50 µm core reference cable. Receive Section PIN photodiode. Spectral response 400-1100 nm. Calibration referenced to 850 nm, traceable to N.B.S. Level: dBm mode: +3dBm to -65dBm at 850 nm dB mode: 51dB (calibrated to -14.0dBm) @ 850 nm Accuracy: dBm mode: +/-5% at 850 nm dB mode: +0.5dB at 850 nm Resolution: 0.1 dB Reference Cable (Standard) Length: 1 meter Type: 50/125 µm Numerical Aperture: 0.21 Power Batteries: Two rechargeable Ni-Cad batteries; 6.0 volt, 450 mAH (Gould 402038-5 or equivalent). Continuous Operating Time: 30 hours receive only. 6 hours transmit on (at optical oulput, -20 dBm). 4 Specifications (cont.) Battery Charge: 115 Vac, 60 Hz 230 Vac, 50 Hz (optional) Charge Time: Overnight (14 hours minimum full charge) Power Indicators: Display; LO BAT Panel; BAT CHG LED Environmental Storage Temperature: Operating Temperature: Humidity: Altitude: Physical Height: Width: Depth: Weight: -40°C to 60°C -1 0°C to 40°C 95% at 35°C 40% at 50°C (non-operating) 15,000 meters 6.5" (165 mm) 4.5" (114 mm) 6.0" (152 mm) 3.5 lbs. (1.56 kg) 5 Figure 1. The T312B Optical Attenuation Test Set 6 Panel Controls and Connections General This section describes the function of the display, switches, controls and connectors located on the front panel of the Model T312B test set. The front panel layout is shown in Figure 3-1. Display The display is a 3 1/2 digit LCD type. In the LEVEL dBm mode, absolute optical power is indicated with reference to 0 dBm. In the AlTEN dB mode, no sign appears in the display as attenuation is a measurement of loss in dB of the unknown to a reference. The resolution of the display is 0.1 dB. When battery voltage falls below a predetermined value a LO BAT indicator appears in the upper lefthand corner of the display. If the set is continued in use, an automatic shut-off turns the set off to prevent battery drain. Function Related The TRANSMIT switch is a three position toggle switch, TRANSMIT-OFF-TRANSMIT (MOM). In the up position, optical power is transmitted continuously; in the center position, the transmit power is OFF, and in the down position, the transmit power is on during the time the switch is held down. The display switch is a two position toggle switch. The up position displays AlTEN in dB and the down position LEVEL in dBm. The ATTEN 0-ADJ pot is used to set the display to 00.0 in the ATTEN mode with a reference cable attached between TRANSMIT and 7 Panel Controls and Connections (cont.) RECEIVE ports. The TRANSMIT switch is set in the up position during adjustment. Power Related The PULL ON switch turns the set on. When the cover is closed, the set is automatically turned off. The 115V AC or 230V AC (factory option) power cord plug is located on the right side of the set. When AC power is applied, the BATT CHG light turns on and indicates the battery is charging. 8 Operating Instructions Power The set is powered by internal rechargeable Ni-Cad batteries and recharged by 115V ac or 230V ac, 50/60 Hz. The Ni-Cad batteries are 6 volt, 450 MAH rated. Power is applied to the set by operating the PULL ON power switch. The power cord is stored in the cover and plugged into the recessed plug on the right side of the set. Low battery is indicated by LO BAT designation appearing in the upper left hand corner of the LCD display. Battery recharge occurs when the ac power cord is plugged in. Charging takes place with or without the power switch on. If the set is continued in use with low battery, an automatic shut-down is activated to turn the set off. This prevents possible cell reversal caused by deep drain of Ni-Cad batteries. The set is reactivated when ac power is supplied as indicated by illumination of the LCD display. Reference Cable Each set is provided with a one meter reference cable of the type specified except for the T312B-17 where reference cable and connector accessories are ordered separately. The reference cable should have the same corelcladding diameter and numerical aperture as the cable under test. The reason for this is to provide a common mode of light propagation since anenuation is a log function of the ratio of the test cable to the reference cable power level. Loop Around Tests General Loop around testing is done with a single T312B test set. This is a convenient way to measure reels of fiber 9 Operating Instructions (cont.) optic cable or to measure installed cable with a patch cord at the far end connecting the pair of fibers being measured. Fig. 4-1 illustrates the connections. Measurement should be made in the direction of transmission intended in the installed system as loss is not identical in both directions. Cable Reel Testing Test Set Up Loop around test is performed by removing the reference cable and the optical fiber in-line bushing from the inside cover of the T312B test set, cleaning the fiber faces with a lint free cloth and connecting the reference cable to the TRANSMIT and RECEIVE ports. Caution: Optics dust covers should be kept in place when the set is not in use. Activate the PULL ON switch, set the display switch to the LEVEL dBm position and turn on the TRANSMIT switch. The display wilt read the optical power level available to the RECEIVE port in dBm. NOTE: When making measurements with battery source, it is recommended that the TRANSMIT (MOM) switch position be used. This will extend the time between battery charges.Set the display switch in the ATTEN dB. Measurement Turn off TRANSMIT switch, disconnect the reference cable from the RECEIVE port and connect to near end of cable under test using the in-line bushing supplied. The far end of the cable is connected to the RECEIVE port as shown in Fig. 4-1. Clean ends of test cable with lint free cloth prior to making connections. Turn TRANSMIT switch on and read optical attenuation of the test cable on the LCD 10 Operating Instructions (cont.) display. Optical power level of the far end of the cable is read on the display by setting the display switch to the LEVEL d8m position. Installed Cable Testing The T312B must be field calibrated, at the test location, prior to making a loss measurement. To calibrate the unit proceed as follows: 1. Attach the reference cable to the TRANSMIT and RECEIVE ports. 2. Select the TRANSMIT mode of operation. 3. Adjust the ATTEN / 0-ADJ potentiometer to give a 00.0 dB reading on the display. The T312B test set is now field calibrated and cable testing can be performed as shown in Figure 4-2. (A craftsperson is required at each end of the cable and voice communication must be established.) Using two T312B test sets, the cable is tested two fibers at a time (one in each direction). Fibers must be tested in the direction of transmission for correct loss measurement. Receive Only Tests The T312B test set is useful as a power meter to measure optical power level of system lasers or LEDs and their associated cables. Measurements may be made at the source using a system patch cord or at the far end of the system cable. The reference cable supplied with the set may substitute as a patch cord. The display switch is set in the LEVEL mode and optical power is read on the display in dBm. 11 Operating Instructions (cont.) Bare Fiber Adapters General Bare fiber adapters are used during installation of fiber optic cables to facilitate system connection to the test set. The T312B display switch is positioned in the LEVEL mode and optical power level is read. As eachsplice is made, the level is compared to a predicted value to determine the acceptability of the splice and cable. The set is used to monitor the alignment of fibers prior to splicing and indicates maximum level when the best alignment is achieved. LEVEL Measurement If provided, the bare fiber adapter is attached to the RECEIVE pod. The fiber is cleaned and stripped as recommended. Index-matching oil is added to the fiber end which is inserted into the bare fiber adapter The fiber is clamped in place and level read on the display in dBm. 12 Figure 2. Loop Around Testing 13 Figure 3. Testing Installed Cable 14 Maintenance Battery Replacement Under normal use and periodic charging the batteries will provide satisfactory operation indefinitely. Should the batteries require replacement use the following procedure. 1. Remove four large Philips Head screws from the front panel. 2. Carefully lift the front panel assembly out of the case. 3. Remove two Philips Head screws which secure the battery holder. 4. Note polarity of batteries and replace accordingly. 5. Reinstall using the reverse procedure. Cleaning TRANSMIT and RECEIVE ports The Model T312B is provided with a dust cap for each port. The caps must be in place whenever theunit is not in use to prevent foreign material from entering the port. Should any foreign material enter the ports, a cleaning agent that leaves no residue must be used to remove it. Fuse Replacement The Model T312B has no replaceable fuse. The unit is protected by a limiting device in the power transformer. 15 Service and Repair 1. Call Wilcom Customer Service. Support personnel will determine if the equipment requires service, repair or calibration. 2. If the equipment must be returned to Wilcom for service, Wilcom Customer Service will issue a Return Material Authorization (RMA) number and the following address for return: Wilcom 73 Daniel Webster Highway Belmont, NH 03220 TEL (800) 222-1898 (USA only) or (603) 524-2622 FAX (603) 524-3735 www.wilcominc.com IMPORTANT Never send any equipment back to Wilcom without a Return Material Authorization (RMA) number. 3. Pack the equipment in its original shipping material. Be sure to include a statement or report fully detailing the defect and conditions under which it was observed. Also be sure to include a contact name and telephone number. 4. Return the equipment, prepaid, to the above address. Be sure to write the RMA on the shipping slip. Wilcom will refuse and return any package that does not bear the RMA. Ordering Information Orders for any of the Wilcom products and any of their optional accessories should be directed to the address shown above. 16 Warranty All products are warranted against defects in materials and workmanship. This warranty applies for a period of two (2) years from date of delivery, except for Fiber Optic instrumentation and equipment which have a one (1) year warranty on parts and two (2) years on labor. (The only exception in the digital testing equipment is the D550 Shark, which has a warranty of one (1) year from date of delivery.) Wilcom's obligation under this warranty is limited to servicing or adjusting each instrument returned to its factory within the warranty period, and to replace any components found to be defective. If determined that the defective condition is a result of misuse or abnormal operation, repairs will be billed. LIMITATION OF WARRANTY The foregoing warranties are the exclusive warranties provided by Wilcom. Wilcom will not be liable for any special, indirect, incidental or consequential damages whatsoever resulting from loss of use, loss of data or loss of profits arising out of or in connection with the use or performance of the product, even if Wilcom has been informed of the possibility of such damages in advance. All implied warranties, including without limitation warranties of merchantability and fitness for a particular purpose, as well as warranties arising from a course of dealing or usage of trade are expressly disclaimed. PROPRIETARY INFORMATION The information contained in this manual is the proprietary material of Wilcom, and may not be reproduced, used for manufacturing purposes, or disclosed to others for any use without written permission from Wilcom. 17