Guide IR518 has just come in for repair :) - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: October 25, 2018, 12:35:20 pm
content: I was recently asked if I would look at a faulty Guide IR518 thermal scope/camera.It arrived today for assessment. I tend to avoid Guide products as they are often somewhat 'agricultural' in design and build. Having briefly looked at my new patient, however, I am quite impressed with its exterior. What I find inside will be very interesting to me.The camera is not my property so I will have to be careful what I post by way of pictures out of respect for the owner and their privacy. I will see if I can at least provide an insight into the units internal design however. Hopefully that may help others to assess the quality of the product before buying one, or even help in the repair of other units.The fault is "no thermal image" but the unit appears to boot correctly and I can hear an FFC flag solenoid activating in harmony with a 'C' symbol on the screen. Time will tell whether I can repair this unit as no schematic or deep technical information is available for it (as is the case with most thermal cameras).Something to challenge my brain a little maybeMore on this when I get time.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: October 25, 2018, 12:43:01 pm
content: For those interested, the IR518 user manual is available here......https://celte-srl.com/wp-content/uploads/2015/12/IR518-MAN-EN.pdfIt retails at around £3K in the UK.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: October 28, 2018, 12:49:09 pm
content: No work carried out on the IR518 yet due to other commitments but I thought I would detail my initial steps when assessing such a 'patient'. Note that these are carried out before any disassembly work is started.Much like a conscious human patient, it is good practice to gather as much pertinent symptom data as possible before knocking them out and 'diving in'Some techs like to dive in and start looking for obvious issues in order to save time. That is not me. Slow and methodical is the approach that has served me well over the years. This is especially important when no service manual is available for diagnostics.Once I start work on this patient I will carry out the initial symptom assessment as follows:1. Visual inspection of casing looking for any evidence of impact, fluid ingress or other unusual signs that could suggest the failure mode.2. If safe to do so, connect a current limited laboratory power supply to the patients power input terminals. Set current limit to approximately 150% of expected draw (taken from specifications). If no current draw is known and camera is uncooled, set current limit to 1A. If a cooled camera, the current limit needs to be set at around 5A.3. Press the power button on the patient. Any signs of life ? Monitor the current draw and any variance as the unit goes through its start up sequence (boot). It is not unusual to see a short duration higher current draw that settles to the nominal after a few seconds.4. Is the screen active and displaying the graphics overlay ? Are any warnings or self test fails present ?5. Check any external video feed from the patient to check for a display on that port.6. Has the patient initiated an FFC event and does it continue to do so approximately every 120 seconds ? (more often after initial boot) Is the FFC event accompanied by the sound of a mechanical shutter/flag operating ? Does this sound "normal" or muted ? (Jammed shutter/flag or low drive)7. Is there any thermal image data present on the display ? Is the spot temperature meter showing a sensible measurement ?8. If no thermal data is present on the display, is noise present ?9. Can different menu's be accessed via the user interface and do they appear to be operating correctly ?10. Can the patient be placed into the "off" condition from the user interface ?These initial checks provide me with useful data before I even start to delve inside the casing.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: October 30, 2018, 04:42:04 pm
content: Currently working on the IR518.Completely stripped down to individual PCB's at the moment.Now I recall why I hate Guide cameras and rarely work on them !The b*stards even remove the chip markings !I already hate this thermal coreFraser

author: Fraser
author_rank: Super Contributor
timestamp: October 30, 2018, 04:50:52 pm
content: A couple of highly compressed pictures from my iPad (pretty poor)I can also advise that the microbolometer used in the IR518 is from the venerable ULIS (France) stable of FPA's. It is type UL 03 16 2.A decent microbolometer alone doth not maketh a decent thermal camera thoFraser

author: Fraser
author_rank: Super Contributor
timestamp: October 30, 2018, 09:44:15 pm
content: A quick summary of the situation with the IR518 camera.Current draw: Initially 1.2A while Peltier element heats microbolometer die. Draw reduced quickly to 820mA which is the units normal operating current (4W)Camera contains two microprocessor systems - The user interface system and the Microbolometer Core system. The User interface system is operating normally and sending the correct start commands to the core. The core starts and goes through its POST process but this is not displayed on the user screen. The FFC events are present and continue as would be expected. A manual FFC event may be instigated via the user interface. There is video getting from the microbolometer core to the display but it contains no thermal image or POST information.The build quality of the camera case is OK but the core is the usual Guide mediocre quality with some less than great SMD soldering in places. The PCB's are mediocre quality and finish. I had to trim one PCB that had never fitted properly since production due to poor PCB edge finishing. The overall feel of the core is pretty cheap and nasty really. The best bit is the ULIS microbolometer but even that has a pretty poor mounting system. Some crude sheet metal 'heatsinks' draw the heat out of the FPGA Memory and microprocessor chips. The heatsinks get quite warm so the inside of the camera case likely gets warm as well. I found just one temperature sensor mounted 'off core'. That Single sensor measures the air temperature around the front of the core and is not in direct contact with any metalwork. The lens temperature is not directly monitored.Guide think it necessary to protect their design by grinding off the major IC's identity. That really annoys me as it makes repair so much harder when you have to first guess the identity of an IC in order to obtain its datasheet. Another reason why I do not normally repair Guide products.General mechanical build quality is mediocre. Parts have been glued together at the factory as well as screwed with self tapping screws because the threads were stripped out during production ! Not a great start !Would I recommend spending £3K on one of these IR518's or others of the same ilk ? Nope, definitely not.The core is reassembled now for the next stage in the diagnostics...... dynamic testing and probingFraser

author: Fraser
author_rank: Super Contributor
timestamp: October 31, 2018, 01:00:21 pm
content: So what will be my next steps in the diagnosis process ?With the major IC's anonymised life becomes challenging. They will be placed under a microscope in an effort to find any remaining identifying marks but that may well be fruitless.I have decided upon a two pronged attack. I will try to gather IC datasheets for the chipset but I will also jump to the probing stage of the investigation.Those trained in fault tracing will be familiar with the 'half split method'. I use this to reduce the potential fault landscape and it often enables me to focus on a specific PCB, or part thereof. Other approaches include the standard data path testing front to back, or back to front. That is to say, you follow the Data from its origin, through any processing stages and to its eventual destination. The reverse is also possible where a lost data input along the chain is suspected. This is more suited to analogue circuits really as data is not always simple to trace through VLSI systems.I know that the UL 03 16 2 microbolometer is the origin of the systems scene data. I also know that it requires certain specific inputs in order to operate and that it produces an analogue 'Video' signal output on one pin. The 'video' signal is RAW, it is not composite video, it has no sync information within it. It is the RAW output from the ROIC pixel readout. That video signal will only be present and correct if the microbolometer ROIC is 'happy'. To be 'happy' all inputs to the ROIC and configuration commands must be correct. The microbolometer video output is therefore a logical place to start the probing investigation. If there is an incorrect signal at that point, nothing else downstream will be correct and the investigation will move to the microbolometer inputs and configuration.If all is well with the microbolometer video output the investigation moves to the various video signal processing stages in the system. The video signal is first converted from the analogue domain into the digital domain using a fast ADC. From there it enters the video processing stages and that is where things become complicated when it comes to probing and diagnostics. The identity and pinout of the VLSI IC's is very helpful here.My current assessment of the situation is that the microbolometer MAY be functioning as the FFC events are present. It also could be that the Microbolometer is NOT functioning but video processing stages are carrying out their usual FFC routine and just 'seeing' a null input. The good news is that the core appears to have a functioning operating system so hopefully we are not looking at an OS fault or corruption.There will be a video processor IC in the core that is responsible for the DSP on the video coming from the microbolometer video output. The video will be processed and then combined with the Overlay graphics for the display. The Overlay graphics and menu system all function correctly so it would appear that either the video processor has lost its input from the microbolometer signal path, or it is suffering a fault in its own realm. It would be great to identify the video processor so that signal probing can be carried out on its pins. In the half split method the input and output of that IC would be key check points.Well this will have to wait as I am off to a Wedding. I shall start the microbolometer checks tomorrow.Oh...... is anyone wondering how I will identify the various pins on the microbolometer ? An important questionI already have the 03 16 2 pin out and datasheet. Guide have also helpfully labelled the pins use on their microbolometer PCBA quick Google search finds a datasheet for the UL 03 16 2 as well.http://www.chronix.co.jp/chronixjp/products/picture/ulis/pdf/UL03162JP.pdfHow will I probe the core when it is a 'stack' design ? It is an arduous task involving destacking, soldering of fine wire taps to points of interest, restacking and testing. The core stack sits in the middle of a 'pin board' and the test point fine wires extend out from it to test points surrounding the core. The unit can end up looking like a flipping May Pole on the test benchIt is an arduous and time consuming process that I do not enjoy, but there is little choice as the stack must be complete to operate. The OEM has the benefit of either individual PCB test jigs or connector extender ribbons to 'explode' the core. Such is justifiable if dealing with a lot of one model of core. I did such when diagnosing and repairing the 21 ARGUS 2 thermal cameras and it saved a lot of time and effort.What is a May Pole ? .... look here.....http://projectbritain.com/mayday/index.htmlFraser

author: Chanc3
author_rank: Frequent Contributor
timestamp: November 03, 2018, 05:05:43 pm
content: Hey FraserGreat read, as always. Am following with great interest!

author: Fraser
author_rank: Super Contributor
timestamp: November 03, 2018, 05:24:10 pm
content: Sadly not as much progress as I would have liked. Family commitments have taken priority this week. Plus this particular investigation is frustrating to say the least.Do not underestimate how much I dislike manufacturers who remove chip numbersIt is a nightmare working on this core as a result. A good name for it would be 'time gobbler' ! No wonder no one wants to service Wuhan Guide cameras ! Normally by now I woukd have created a full block diagram with all the main IC captured and the points of interest. I am still hunting for likely candidates for the various anonymous IC's.Thankfully I think the client is patient and I am not charging for this particular fault investigation. Charging a customer the normal hourly labour rates for a Wuhan Guide camera repair would likely make it an uneconomic repair for the owner.In case anyone missed my previous comment on the matter.... unless it is bargain basement cheap, I recommend you avoid Wuhan Guide products. When they break, which they tend to do, you will likely have to find a new camera as I doubt anyone will touch it for repairI am faced with a situation that I hate. This camera may be unrepairable due to the absence of essential information that I need to both diagnose the failure and/or source the replacement part due to part anonymisation.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: November 05, 2018, 12:06:29 am
content: A very knowledgeable fellow forum member has given me a great hint on the true origins of the Wuhan Guide Core design. With this new information I may just be able to make some progress. We shall see.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: November 26, 2018, 01:25:47 pm
content: Just a very quick update on this investigation.......It is very slow going and quite frustrating. Reverse engineering such high density multi PCB stack designs is never easy but when you cannot identify some significant IC's it becomes almost more effort than its worth.This core is very frustrating to work on and the sensible side of me says stop now and return the unit to its owner as beyond economic repair. I am not charging the owner for the repair though so the B.E?R element is less applicable. Another part of me hates to be beaten and wants to battle on with this horrid little coreThe owner is aware that the unit is a pig to work on and appears content for me to carry on. It's one of those slow progress projects you have to leave for a while and return to as it gets frustrating.Will I work on another Wuhan Guide camera ? ........ I never say never, but I doubt I will take on another any time soon.I see that someone bought a Wuhan sourced VGA imaging core on eBay UK last week for £800. I hope it works well for them but they seem to be pretty awful build qualityFraser

author: Ultrapurple
author_rank: Super Contributor
timestamp: November 26, 2018, 02:09:38 pm
content: Quote from: Fraser on November 26, 2018, 01:25:47 pmI was bidding on that one but lost interest when it went above about £250...I too wish its new owner well.

author: Fraser
author_rank: Super Contributor
timestamp: November 26, 2018, 02:26:51 pm
content: Ha ha, I bid on it as well .... and lost interest at £250 ...... we think alike !I spoke to the seller. He sent me the connection pinout. It looks OK on paper. It is based on a ULIS (or clone of ULIS) microbolometer. Both analogue and digital video was available and control was via RS232 and RS485.As for getting any integration support from the OEM, as the seller suggested..... Hmmmmm I would not count on that somehowAt the right price it was interesting but, to me, £800 was top money for a Wuhan sourced core. As we know, it is not just the hardware that is vital to a good image, it is also the DSP software. That is where Wuhan sourced cameras generally fall down in my experience.I already have a VGA camera in my new DRS pan tilt head so another was not essential but I bid anywayThat unit contains the Venerable DRS Tamarisk core. Quality, Quality, QualityThe complete new DRS pan tilt camera did not cost me much more than the buyer paid for the Wuhan Core. I got lucky though.The buyer may be a member of the forum so we may get to hear more about it and see the imaging that it produces. I hope they are happy with it but if it fails, I want nothing to do with its repair !If the quality of components used on the PCB's is the same as that on the IR518, combined with poor reflow, it may not last that long in serviceFraser

author: Ultrapurple
author_rank: Super Contributor
timestamp: November 27, 2018, 03:22:09 pm
content: Getting a fairly current 640x480 or 640x512 uncooled LWIR camera and lens for £250 is a fairly unrealistic expectation, I think, unless one gets extremely lucky in an auction (at the expense of the seller) or you spot something from a surplus/disposal outlet who doesn't recognise the potential value of what they're selling. I usually see it the other way round, though - disposals merchants often seem to try their luck at an inflated price and invite a 'best offer'. That's why you'll sometimes see things like a length of RG58 cable offered for GBP100 'because it came from the military' when its real worth is maybe the same as it'd cost to post.

author: eKretz
author_rank: Frequent Contributor
timestamp: November 27, 2018, 05:29:54 pm
content: The ONLY thing I hate worse than when they remove the chip markings is when they pot the board in such a way that repairs are a HUGE pain.

author: bap2703
author_rank: Regular Contributor
timestamp: November 27, 2018, 09:16:23 pm
content: Could do both

author: eKretz
author_rank: Frequent Contributor
timestamp: November 28, 2018, 02:23:06 am
content: Bite.Your.Tongue!

author: Bill W
author_rank: Super Contributor
timestamp: November 29, 2018, 05:23:47 pm
content: "Conformal coating is used to hold the parts on the board when the solder paste does not go off "don't you know ............,oryou decide ................Bill

author: Fraser
author_rank: Super Contributor
timestamp: November 29, 2018, 05:49:41 pm
content: Well in the case of the Wuhan Guide core, I can confirm that the SMT soldering is horrendous with components being easily removed with just tweezers ! It is about the worst SMT reflow I have seen on a thermal camera. Dry joint city basically ! If the PCB had been coated in silicone rubber I reckon a few components would have just peeled off with the coating !Did I say I hate working on a Guide cameras ?

author: Ultrapurple
author_rank: Super Contributor
timestamp: November 30, 2018, 09:16:35 am
content: Years ago we developed a simple yet infallible test to check for lead-free-ness.Place a sheet of white paper on the benchHold the PCB a few inches above itTap the board edge with a screwdriver handle.If all the components fell onto the paper, it was a lead-free board

author: Fraser
author_rank: Super Contributor
timestamp: February 15, 2019, 01:58:44 pm
content: Well just to close off this story of Woe regarding the Wuhan Guide IR518I ‘called it’ on the IR518 in January. After much effort and reverse engineering that involved much ‘head scratching’ thanks to Wuhan Guide removing the IC numbers I traced the fault to the Microbolometer ROIC.As Bones on Star Trek would say ... “It’s dead Jim”. At that point the possibility of repair evaporated.If I never see another Wigan Guide thermal camera or scope, it will be too soon !This ‘patient’ was sadly beyond my help, but if you, dear readers, take anything from my tale of woe, it should be to avoid products made by Wuhan Guide like the plague ! If I save someone else from the heartache of Wuhan Guide equipment ownership, it will all have been worth the effort.The owner of the unit has been advised of the sad news and intends to find someone else to repair it. If you repair such equipment, you have been warnedFraser