james.wilson Posted June 27, 2013 Share Posted June 27, 2013 Top post bee securitywarehouse Security Supplies from Security Warehouse Trade Members please contact us for your TSI vetted trade discount. Link to comment Share on other sites More sharing options...
sixwheeledbeast Posted June 27, 2013 Share Posted June 27, 2013 Top post bee Agreed Link to comment Share on other sites More sharing options...
MrHappy Posted June 27, 2013 Share Posted June 27, 2013 You are even getting close to the 30 years life expectancy of semiconductors! interesting, what's your source ? Mr Veritas God Link to comment Share on other sites More sharing options...
bee_man Posted June 27, 2013 Share Posted June 27, 2013 Standard industry knowledge really, still taught to students so I assume still valid. Google for semiconductor bathtub or follow links from wiki : http://en.wikipedia.org/wiki/Bathtub_curve Failures drop drastically in the first few months due to defects then rise fairly quickly around the 30 year mark due to diffusion and other wear out processes, leaving probability of failure looking like a section through a bath tub. Higher temperatures lead to earlier failures. Some components like DRAM have very much lower life span, and things like IGBT power devices are expected to live longer. bee Link to comment Share on other sites More sharing options...
matthew.brough Posted June 27, 2013 Share Posted June 27, 2013 Standard industry knowledge really, still taught to students so I assume still valid. Google for semiconductor bathtub or follow links from wiki : http://en.wikipedia.org/wiki/Bathtub_curve Failures drop drastically in the first few months due to defects then rise fairly quickly around the 30 year mark due to diffusion and other wear out processes, leaving probability of failure looking like a section through a bath tub. Higher temperatures lead to earlier failures. Some components like DRAM have very much lower life span, and things like IGBT power devices are expected to live longer. bee Can tell you're not an installer www.securitywarehouse.co.uk/catalog/ Link to comment Share on other sites More sharing options...
MrHappy Posted June 27, 2013 Share Posted June 27, 2013 Standard industry knowledge really just wanted a nice simple link.... Very old alarms are quite common, very old company cars or computers ain't... Mr Veritas God Link to comment Share on other sites More sharing options...
arfur mo Posted June 27, 2013 Share Posted June 27, 2013 just wanted a nice simple link....Very old alarms are quite common, very old company cars or computers ain't... i have 2 Sinclair C5's - 30 years old and still going strong lol! If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Oxo Posted June 27, 2013 Share Posted June 27, 2013 Not cars are they Link to comment Share on other sites More sharing options...
MrHappy Posted June 27, 2013 Share Posted June 27, 2013 i have 2 Sinclair C5's - 30 years old and still going strong lol! triggers broom ? Mr Veritas God Link to comment Share on other sites More sharing options...
Oxo Posted June 27, 2013 Share Posted June 27, 2013 lol Link to comment Share on other sites More sharing options...
arfur mo Posted June 27, 2013 Share Posted June 27, 2013 as it happens Mr H, also have a 40 year old Broom Speedboat, fitted with a 'massive' 5hp Tohatsu O/B engine . As one C5 is stock 12 volts, the other is a 24 volt conversion, i'm not sure which of the three is actually fastest - or for that matter which one floats the best either! If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Oxo Posted June 27, 2013 Share Posted June 27, 2013 All ***** though! Link to comment Share on other sites More sharing options...
arfur mo Posted June 27, 2013 Share Posted June 27, 2013 true but great fun. bought last year before hose pipe ban - then weather was kack, took the boat out first time a few weeks back over at shepearton mallet canal, surprised how many other boaters were interested in and knew of the boats make. I bought on price simply as a restoration project for me and gkids to work/play on, only paid £450.00 for the whole lot, it looks ruff, due to me wanting to be sure it floats first before putting any money into it. seems at some stage many boaters have owned a Broom', bit like having a 'right of passage', got stacks if advice on original fitting etc. maker is no longer trading, but has its own very busy enthusiasts forum. If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
MrHappy Posted June 27, 2013 Share Posted June 27, 2013 as it happens Mr H, also have a 40 year old Broom Speedboat, fitted with a 'massive' 5hp Tohatsu O/B engine . ohh, tihs would be so much better than a big lottery win! Mr Veritas God Link to comment Share on other sites More sharing options...
arfur mo Posted June 27, 2013 Share Posted June 27, 2013 ohh, tihs would be so much better than a big lottery win! and why i don't let the MOL come with us If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
EdGasket Posted July 8, 2013 Author Share Posted July 8, 2013 Finally found time to investigate: 1) The panel battery volts drop to 9.8v with the mains disconnected; should be 12v so I need to repalce that. 2) Measured faulty PIR circuit resistance at panel > 1Kohm whereas other PIR circuits less than 5 ohm at panel. Measured PIR at the PIR, 0.2 ohms. Cleaned up faulty PIR contacts and wire ends and reconnected; resistance at panel now 7 ohms. Conclusion: Oxidised trigger connections to PIR causing high resistance and false alarm. New Yuasa NP2.8 - 12 battery ordered for £ Note: Regarding electrolytic capacitors ageing/bulging - this only affected a batch of Chinese capacitors over a few years around around the late 1990's and early 2000's where they had got the electrolyte formula wrong (stolen I think). Capacitors pre and post that era should not suffer from the problems described earlier in the thread. Being an earlier panel, my caps still look like new; no bulging or leaking. Ed NO PRICES IN THE PUBLIC AREA If you are unsure of the rules of this forum please familiarise yourself with them here Link to comment Share on other sites More sharing options...
petrolhead Posted July 8, 2013 Share Posted July 8, 2013 Glad you got it fixed, but your spreading misinformation about caps not going high esr with age. Chinese capacitor syndrome caused caps to fail as early as 3 years old. Even perfect caps dry out with age and by the time they are 15 or so they increase their equivelant series resistance to the point where they are less effective at smoothing out ripple and transients. Testing with a capacitance meter doesn't always reveal the problem you need to use an esr tester. The first thing you do when restoring old electronics is replace the electrolytics, then look for open resistors and shorted semiconductors. I have spent years refurbising CRT monitors and power suppy units and done a stint in a lab testing new designs and doing failure analysis. But whatever, you don't live next to me so I couldn't give a **** if your alarm goes off frequently. Link to comment Share on other sites More sharing options...
fozzies Posted July 9, 2013 Share Posted July 9, 2013 As Petrolhead said How can that be best answer, mods should remove it! Link to comment Share on other sites More sharing options...
cybergibbons Posted July 9, 2013 Share Posted July 9, 2013 Ed, I need to agree with these guys. I'm not an alarm installer. I do have a degree in EE and spent a summer doing MTBF calcs for telecoms equipment. It is always the electrolytics that go first. At rated temp (85degC), they degrade significantly in just a year of operation. At 60degC (common inside an unvented box in the PSU), you might get 50,000 hours before degradation. It's not just cheap caps - these figures are for good Panasonic caps. The bad caps of the early 2000s got overstated, but now it seems like the opposite happens. Speak to someone who repairs TVs - at least 50% of the time it will be a cap. I have a blog, some of which is about alarm security and reverse engineering:http://cybergibbons.com/ Link to comment Share on other sites More sharing options...
james.wilson Posted July 9, 2013 Share Posted July 9, 2013 Never had a disputed best answer before. Need a process for hoe to deal. Ill have a chat with the mods. securitywarehouse Security Supplies from Security Warehouse Trade Members please contact us for your TSI vetted trade discount. Link to comment Share on other sites More sharing options...
RichL Posted July 9, 2013 Share Posted July 9, 2013 Never had a disputed best answer before. Need a process for hoe to deal. Ill have a chat with the mods. Norman? Surely he's got enough to do. Originally said by Charles Babbage On two occasions I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question. Link to comment Share on other sites More sharing options...
james.wilson Posted July 9, 2013 Share Posted July 9, 2013 Lol securitywarehouse Security Supplies from Security Warehouse Trade Members please contact us for your TSI vetted trade discount. Link to comment Share on other sites More sharing options...
EdGasket Posted July 9, 2013 Author Share Posted July 9, 2013 Re. Best Answer - I have no idea why it is flagged as best answer, I was just reporting what I found and clicked the button that said 'Mark Solved' as i had found the problem. Apologies if that has upset some people; wasn't my intention. Ed Link to comment Share on other sites More sharing options...
james.wilson Posted July 9, 2013 Share Posted July 9, 2013 Ah fair enough. securitywarehouse Security Supplies from Security Warehouse Trade Members please contact us for your TSI vetted trade discount. Link to comment Share on other sites More sharing options...
norman Posted July 9, 2013 Share Posted July 9, 2013 I come from a TV repair background, albeit 20 years ago and would confirm the issues with caps, heightened more when subject to extreme temperature. Norman? Surely he's got enough to do.kiss my fat hairy what? Nothing is foolproof to a sufficiently talented fool. Link to comment Share on other sites More sharing options...
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