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7. Lock up adjustment points. Prism assembly is now adjusted and calibrated correctly 

 

If the whole prism assembly is well tightened and is not badly knocked, it should not actually go out of calibration. 
So every month a quick check will ensure it is calibrated. If in use components are being placed off centre the prism 
assembly may need calibration. Remember always lock pick-up and vision arms (using the black locking levers at the 
rear of the arms) before calibration is carried out and lock arms during alignment and placement. 

Summary of Contents for D2

Page 1: ...www pdr rework com version 2 01 PDR IR REWORK SYSTEMS OPERATORS MANUAL SOFTWARE CONTROLLED SYSTEMS X410 XT3 XT5 D2 D3 D35 E2 E3 E6 ...

Page 2: ...www pdr rework com ...

Page 3: ...rstly prior to use we recommend that the system be professionally installed and commissioned by a certified PDR representative This manual is structured to assist a technician with the operation and maintenance of the PDR equipment It contains a technical description to enable the reader to understand the design features of the equipment The safety section of the manual explains the inherent dange...

Page 4: ...ning or tissue damage When placing work under the lens ensure the Infra Red spot is switched off to prevent unwanted localised heating Death or serious injury may result from electric shock It is therefore essential to isolate the equipment from the mains before commencing repairs To eliminate the possibility of burns allow time for the equipment to cool before commencing maintenance Cautions Dama...

Page 5: ...uring working operation and the following results obtained On a non reflective surface i e FR4 substrate if one s eye is placed 150mm away looking down at an angle one could be subjected to approximately 0 9mW cm2 at full power On a reflective surface i e polished aluminium at a normal distance of 300mm one would be subjected to approximately 0 9mW cm2 These measurements were deemed to be safe and...

Page 6: ... introduced early 2000s and have been developed to be able to be upgraded from a basic system without BGA alignment to the full system as seen below Typical Configuration includes Focused IR Component Heating 750 3000W Quartz IR PCB Preheater Precision XY PCB Table Precision Pick up System with Macro Micro Z movement and Rotation CCTV Prism BGA Alignment Advanced Software Control with PDR T5 Contr...

Page 7: ...www pdr rework com Precision XY PCB Table Quartz IR PCB Preheater Advanced Software Control ...

Page 8: ...ciency Lighting The lighting should not be so bright as to prevent the operator from viewing the IR spot or the digital controller s L E D displays Fume Extraction depending on the process it may be necessary to install an integrated fume extraction system to comply with operator safety Electricity The electrical supply should be of the specified voltage sufficient current capacity for the stated ...

Page 9: ...nd below the melting points of the metals being joined The bonds are formed by the formation of intermetallic compounds an irreversible chemical process and or by diffusion or absorption a physical process When joining eutectic tin lead solder 63Sn 37Pb and other high tin alloys including lead free alloys with copper various intermetallic compounds are formed on the copper side and on the solder s...

Page 10: ...ty solder joints on all of the components leads on a particular assembly and do to this consistently The reflow process involves heating the component leads PCB pads and solder solder paste above the melting point of the bonding alloy solder so that the solder melts bonds and forms a homogeneous fillet connecting the leads to the pads As well as controlling solderability parameters materials conta...

Page 11: ...ead based solders 240 250 C for typical Lead free applications The maximum ramp rate in this zone is typically 2 4 C second Reflow Soak Zone The Reflow Soak time the period of dwell time at the peak reflow temperature typically 20 60 seconds should be long enough to allow for all of the joints to reach temperature and form the bonds Too long a soak time can lead to excessive intermetallic formatio...

Page 12: ...flow in the original production process Temperature Profile In operation the component is put through a full reflow procedure The PDR Rework system uses a software controlled system 5 or 6 stage process including 2 preheat stages a soak zone followed by reflow final soak and cooling stages All parameters such as temperature levels and ramp rates are precisely controllable as recommended by board a...

Page 13: ... delivers 750 3000 Watts medium wave IR In normal use approximately 30 40 of the energy is provided by the top heat and 60 70 of the energy is provided by the back heat The above diagrams show how the energy is applied to a component and PCB how the component temperature is measured and also a typical thermal profile The Key Parts of the PDR System Infra Red Lamp Lens System The IR lamp lens syste...

Page 14: ... in the lamp housing at the top of the unit The lamp emits short wave IR radiation at approximately 1 0um Upper Lens Assembly The purpose of the upper lens assembly is to collimate the radiation from the IR Lamp into a formatted beam before projection through the iris assembly ...

Page 15: ...and allows the user to view the spot Back Heat PCB Preheater The back heat is applied by a 750 3000w medium wave Quartz IR emitter controlled by the software digital controller and performs three functions 1 It preheats the PCB and also helps avoid overheating the component 2 It reduces the risk of thermal shock and PCB de lamination PCB blistering 3 It counteracts the heat sink effect of heavy tr...

Page 16: ...re PC controlled using PDR software The main PDR Type 5 control box is used to provide electrical power to the various functions top heat back heat vacuum thermocouple inputs etc Detailed operating instructions are described later in the next section Control and Settings Typical software control screens look like those below ...

Page 17: ...stem will monitor the component temperature with non contact IR sensor T C 1 and then follow the temperature target controlling the component temperature and ramp rate by increasing or decreasing the topheat power In Auto Mode the component temperature will always closely follow the target automatically In addition PCB temperature is also monitored and controlled T C 2 is used to monitor PCB tempe...

Page 18: ...CB and component have been selected The folder name the PCB indent The file name the profile component type ident location etc Folder Name Topline 967001 PCB ident File name BGA 225 U1 F700 01 lmd Starting and Stopping Start begins the cycle Stop stops the cycle Vacuum and Align Turn Align On Off ...

Page 19: ...sts the intensity of the component heating to follow a desired maximum ramp rate and also controlling maximum PCB temperature limit It can also pause to wait for a minimum PCB temperature to be achieved and only steps through to the next phase when temperature targets are reached Profiling is a lot easier A mixture of ramp rate temp and time targets can be used In this example there are 6 zones 1 ...

Page 20: ...the software control We strongly recommend you open a default profile Auto Mode and practice rework on dummy boards and components before launching into action on your live PCBs Profiles that you develop will probably not vary very much from original defaults and they generate better understanding of reworking with the PDR Rework system For more detailed technical information contact your PDR repr...

Page 21: ...l make the software wait for the previous zone s B H PCB Temp limit to be met before continuing with zone 2 Ramp rate C Sec Component Temperature If a ve value is set time for zone T H power will be adjusted to always maintain this ramp rate If value 0 the software will maintain temps for the time duration set Soak a ve value cool down the software will control the rate of cooling if a T H power i...

Page 22: ...0 40 30 40 30 15 30 F200 60 40 30 40 30 15 30 F400 90 45 30 40 40 15 30 F700 90 120 45 60 30 40 40 60 15 30 30 60 Typical Temperature Target Settings C Zone Preheat1 Preheat2 Soak Reflow Dwell Cool Component T C1 100 150 150 220 230 220 230 150 Lead free T C1 100 170 170 240 250 240 250 150 The tables only provide general guidelines as many factors influence the required settings i e position of a...

Page 23: ... and fluxes required Switch on and warm up The following simple procedure will warm the system up a Switch on the PDR T5 Controller Lightbox and PC b Allow system to warm up 5 to 10 minutes Selecting a Profile to use The following simple procedure will get you started a Press open bottom left in control panel b Select required PCB this is the folder containing your component profiles c Select comp...

Page 24: ...www pdr rework com ...

Page 25: ...oard lmd to be used with the F700 lens attachment and used for most large QFP PLCC and BGA components on a small medium sized PCB This profile contains all the parameters needed powers times temperature targets zones etc as displayed under the Settings tab Thermocouples Up to four thermocouples T Cs can be used and displayed Only T C 1 and 2 are used for control T C 3 and 4 if selected are only us...

Page 26: ...ion height adjuster The correct lens to PCB distance will be dependent on the lens attachment selected Use the above table as a guide Note Lens to PCB distance can be set with a rule or by moving the lens until the spot is sharply focused when the machine is on and alignment is pressed set the iris to the half open position and press the alignment button in the software control panel Tools and flu...

Page 27: ...he procedure while preparing to rework SMT BGAcomponents is as follows Switch on and warm up Select settings or profile required for PCB component Sort aim and attach thermocouples Select lens attachment and set lens height spotsize Sort tools and fluxes required ...

Page 28: ...lder issues all need to be constantly reviewed and effectively controlled It is not easy but it is important to exercise all the same care in SMT BGA rework as is applied throughout the various stages of a typical SMT line BGA Alignment System and Placement The PDR Rework system can be purchased with or without a CCTV Prism based BGA alignment system In practice it may not be needed as BGAs are of...

Page 29: ... conduct micro adjustments First adjusting component rotation then adjusting X and Y positioning with micrometers 4 Adjustments done now retract move Prism out of the way to the left Now carefully place component onto fluxed pads Next move the Pick up up and out of the way Finally position move the IR Lens system into position ready for reflow ...

Page 30: ...y and inspect Detail Procedures Soldering 1 De flux and cool the PCB remove old flux residue and generally prepare the PCB 2 Put PCB in jaws and position under lens 3 Press Align position component target in the centre of the IR spot and adjust spotsize to be approx 6 10 mm larger in area than the component area 4 Apply flux to solder pads use gel on a cooled board for best activity If the existin...

Page 31: ...cally cycle through the Preheat Reflow Soak and Cool Zones 5 At about 150 C the flux will start working There will be two bursts of smoke flux fumes and on the second one you should have reached reflow at about 200 210 C for leaded 230 240 C for Lead free The software takes you to Peak Reflow component temperature and Soak Zone 6 Remove component with tweezers vacuum pen or the vacuum pick up 7 Re...

Page 32: ...m the equipment with a clean cloth Periodically clean the exposed surfaces of the equipment with a soft cloth slightly moistened with water The lens assembly should be cleaned using Iso Propylalcohol IPA Care should be taken to ensure that the lens cloth is clean as any contamination of the cloth could cause scratching of the glass surfaces Caution do not use solvents for cleaning any part of the ...

Page 33: ...roller use the correct USB Serial adapter vacuum working and effective the pick up nozzles may need cleaning with IPA alcohol Backheat working and effective quartz heater panels should glow slightly at full power Topheat working and effective measure IR lamp voltage at full power There is a measuring point inside the top of the lens unit Undo 3 screws to open the top panel to reveal a ceramic conn...

Page 34: ...y rust problems Squareness we set the pick up in its locked position to be over the centre of the backheater With a flat plate or PCB in the jaws we then check the pick up nozzle makes square contact with the surface Pick up a flat set piece and lower to the surface to check it touches down evenly north south east west With the pick up now set and touching the surface we now adjust the IR lens ass...

Page 35: ...surfaces with a dry lens cleaning cloth to remove dust There should be no flux residue on this assembly but if there is moisten the cloth with IPA alcohol to carefully remove any residue Calibrate as follows 1 Place Prism alignment plate in PCB jaws 2 with pick up and vision arms locked pick up top alignment plate 3 Lift plate to top of pick up z axis travel ...

Page 36: ...late and lower top plate into focus 5 Look at the CCTV monitor X axis is out below left and Y axis is out 6 Physically adjust the prism assembly to correct the errors Unlock and adjust A to correct X axis error and unlock B and rotate prism body to correct Y axis error ...

Page 37: ...ed it should not actually go out of calibration So every month a quick check will ensure it is calibrated If in use components are being placed off centre the prism assembly may need calibration Remember always lock pick up and vision arms using the black locking levers at the rear of the arms before calibration is carried out and lock arms during alignment and placement ...

Page 38: ... by the mains input and the On Off switch Both fuses are Anti surge T 20mm type 15A 250V Bulb no longer works This may be caused by either a blown fuse the lamp s age corroded lamp pins or a defective lamp socket Lamp Age Life A lamp has a life expectancy of 30 000 cycles or 50 hours at full power If burnt in appearance replace with a new lamp Corroded Lamp Pins White residue on the pins of the la...

Page 39: ...onal charge except as set forth below This warranty covers failure due to faulty materials or workmanship This warranty does not cover the repair of damage to the product resulting from accident disaster misuse abuse unauthorised repairs the attachment of non PDR accessories or non PDR modifications Service under the conditions of this warranty may be obtained by delivering the product during the ...

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