InFocus IN104 Projector - Shuts down a short period after power on? - Page 1
Forum section: electronics / projects

author: birdie
author_rank: Contributor
timestamp: August 18, 2013, 11:04:56 pm
content: I have an InFocus IN104 XGA projector, and its just started playing up. When its powered on, it starts up as normal, and then after a short period of the lamp being on (varies, initial time might be about 15 seconds, after that might be only 5 seconds). Both fans are running, there is no filters so nothing blocking airflow...I checked it again, after it shuts down it won't turn on again until its been left disconnected from the power for a few minutes... and when it shuts down the temp and lamp lights don't turn on... it just hard shuts down, which leads me to wonder if its a component issue, maybe a faulty power supply Cap or something like that?Any suggestions?

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: August 19, 2013, 05:12:25 am
content: Unless someone here has same unit with similar problem there won't be any useful answers unless you can provide more info. Open it up, locate the power supply section, take some hi-res photos so that component markings are visible.These would be my first steps:Do you get expected voltage out of supply?Does it hold expect voltage when internal CPU(s) start booting?Are there multiple supply voltage rails. Are all of them have expected voltage?Perhaps you can probe shutdown pins in regulator(s) you find - what drives them?Something is overheating?Is power supply a separate module in this thing? Can you disconnect it and power up from external DC supply instead and see what happens?...

author: Experimentonomen
author_rank: Regular Contributor
timestamp: August 19, 2013, 11:51:51 am
content: You sure its not the "clean the filters" timer thats expired or the lamp at EOL ?

author: garak
author_rank: Contributor
timestamp: September 01, 2013, 07:35:53 pm
content: Quote from: birdie on August 18, 2013, 11:04:56 pmArc lamps as used in data projectors work by using a large HV pulse to "ignite" the arc, then switch to a lower voltage as the lamp warms up. As the voltage drops, the current across the lamp increases by quite a bit, so a weak PSU will probably cause a brownout reset of the controller at this point. Check the B+ line from the main switcher to make sure it's not dropping out or doing anything silly like that.BEFORE all this, however, check the obvious things. Are all the fans in your unit working? Are you sure? Are their tachos working? The logic on some modern projectors usually allows for a 10 or so second grace period for fans to come up to speed before the lamp drive signal gets killed, others won't start the lamp until the fans are okay.Older lamps require higher voltages to start and pull more current when operating, so your lamp being EOL is also quite possible. You often find that dead lamps will start and run for a run for a few seconds before their current demand exceeds the safety limits for the driver and the supply gets shitcanned by the protection circuit. The time that this takes tends to be shorter if the lamp is warm, so I'd say your unit is a prime candidate for dead lamp syndrome.Other less likely candidates are things like DMD chip temperature and control logic, but it's a bit of a reach.What you didn't mention is if the unit gives you any indication as to what's going wrong. Do you get any abnormal LED indications? From memory most InFocus stuff have RS232 control ports, and many projectors (notably Sanyo) spit out diagnostics and status information on these. I've solved many a problem in half the time by plugging in the serial cable and asking the machine what's wrong. Dig up your manufacturer's control software and/or user manual and give it a try.EDIT: I missed your second paragraph, sorry.Since you're getting a dead unit with no indication that has to be left to sit before it'll turn back on, this sounds like some variety of thermal cutout. These things are riddled with thermal sensors, but most of them will cause soft-faults (i.e. error lights) rather than an all-out fail. However, there's usually a thermal SRCB attached to the main body of the lamp house that will kill the 240v supply to the PSU if it trips. This is worth a look. Double check your airflow and make sure that this breaker isn't tripping too early. If it is, replace it. Do NOT bypass it. Old lamps also run significantly hotter than new ones, so that could be the cause of the tripping as well.EDIT 2:Since you don't sound like you've had much experience on projectors, please be careful. The HV lamp pulse is exceptionally unpleasant, bare lamps can give UV burns (especially to your eyes) and hot quartz glass has a nasty habit of exploding if shocked, or just because it feels like it. You don't want to have any encounter with those hazards, trust me.

author: agonzalezp
author_rank: Newbie
timestamp: March 09, 2015, 01:40:21 am
content: I hope here i can get any help here, I have the same problem, but I noticed that the projector works great if I remove the projector´s top cover, but if I place it back it shuts down in 1 minute. With the top cover removed it works for hours. it does not show anything to go wrong just shuts down, and if I remove the power cable I can turn it on right away, if not removed it takes about 15 minutes bevor I can turn it back on.