Fluke TiR32 Power Problem - Page 1
Forum section: electronics / repair

author: Po6ept
author_rank: Regular Contributor
timestamp: April 16, 2016, 06:25:24 pm
content: I just picked up a Fluke TiR32 thermal camera without a power supply. The previous owner inherited it when his dad passed away and he freely admitted to "trying a few different power supplies I had sitting around" to see if he could get it working. He gave me a 15V DC supply with it, but when I plugged it in to test, I got the distinctive smell of fried components. He told me, after I tried, that he got the same result...He sold it to me "as-is" for $300. I pulled it apart and found a burned diode. The Fluke manual doesn't specify whether the power input is 15VDC or 15VAC, but from the circuit it looks like it would be AC. Power enters through transformer T1 and is rectified by the two diodes, but I don't understand why different part numbers were used for the two diodes. I cannot identify the part number on the burned one.Do any of you have any circuit information before I dig in any deeper?

author: Po6ept
author_rank: Regular Contributor
timestamp: April 17, 2016, 01:25:52 am
content: Answering myself in case anyone else runs across this...The burned component is a Littelfuse SMBJ15A transient voltage suppressor diode.The center pin of the power connector goes through one winding of the transformer to the anode of CR6, a 4A, 40V Schottky diode.The shell of the power connector goes through the other transformer winding to the anode of VR2, the 15V unidirectional TVS diode.Circuit common is at the anode of VR2 and the cathodes of both diodes are connected together.The input appears to be 15V DC, polarity, over-voltage, and transient protected. His 15V power supply outputs an unregulated 20V.After removing the TVS diode, I inserted a current-limited DC voltage at the cathodes of the two diodes and the unit works. It's charging now from my bench supply. It looks as though I got lucky.

author: SeanB
author_rank: Super Contributor
timestamp: April 17, 2016, 09:01:16 am
content: Input overvoltage and reverse polarity protection did it's job, though it sacrificed itself in doing so. Transformer is a common mode choke to reduce emissions.the

author: nixxon
author_rank: Frequent Contributor
timestamp: April 21, 2016, 10:50:34 am
content: I have a Fluke TiRhttp://www.fluke.com/fluke/m2en/Thermal-Imaging/Fluke-TiR.htm?PID=56190It looks somewhat similar to the TiR32http://www.fluke.com/fluke/m2en/thermal-cameras/fluke-tir32-(europe).htm?PID=56194How did you take the case apart? Was it difficult? Do you by chance have any Pictures taken during disassembly?

author: Po6ept
author_rank: Regular Contributor
timestamp: April 21, 2016, 04:32:45 pm
content: It is easy to disassemble, but be mindful of the lens while working on it. I forgot to take photos once I got absorbed in troubleshooting it.- Remove hand strap if required- Remove yellow protective cover. Start by prying it over the hand strap tabs then peel it off.- The battery case cover does not need to be removed to access the main unit.- Remove the four case screws at the perimeter of the screen housing.- Remove the case housing.- Disconnect the screen ribbon cable. The black part of the connector flips up at 90 degrees to release the cable.- Remove the rubber screen backing.- The main board is held in place with four silver screws at the perimeter. Remove these.- Gently lift the main board 1/2 inch.- Remove the upper ribbon cable at the top rear. It is socketed, so gently release the connection by prying the plug away from the socket.- Remove the two cables at the bottom of the board. The ribbon cable connector is not locked so the cable pulls from the socket.I did not have to remove the sensor section to repair mine, so this is as far as I went.There doesn't seem to be any servicing information or schematics available on the web.