SOLVED! Ersa i-Con throws Error 8 on i-Tool, but i-Tool works on another i-Con - Page 1
Forum section: electronics / general

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 04, 2017, 03:19:14 pm
content: Dear forum,I hope you can help me out.Lately I bought an old i-Con (pre 1/1C/1V model). It came with the Power Tool, which is working absolutely flawless.I also got an i-Tool for the station. It is being recognized and heats up as it should be. However, when reaching the process window, the station throws »Error 8 - heating element?«The strange thing is, that the i-Tool works on another i-Con (i-Con 2) without problems. The heating element heats up and returns the correct temperature, but every time the i-Tool reaches or almost reaches the set temperature, the station throws Error 8 and shuts down the triac.Since I found alink to a Russian forum(google translated) describing something similar, I followed the instructions and replaced the triac with a new part. The symptoms described are very similar, station working with Power Tool but i-Tool throws error.Sadly, replacing the triac did not change anything.Any ideas or suggestions?

author: wraper
author_rank: Unknown
timestamp: November 04, 2017, 03:28:35 pm
content: Quoteyou mean triac?It could be a bad contact in connector. Post #31 says about it.QuoteIt says replacing triac did not help.

author: wraper
author_rank: Unknown
timestamp: November 04, 2017, 03:45:06 pm
content: Also this may be error with temperature readout as it happens completely different for power tool and i-tool. I don't have power tool, but it should be purely analog input I think. As of I-tool it could be either time divided digital + analog as i-tool nano or purely digital communication as electronics in full fledged i-tool are much more sophisticated. IIRC second connector on I-CON2, which supports i-tool only, have 2 pins not used unlike 1st connector.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 04, 2017, 03:45:54 pm
content: Quote from: wraper on November 04, 2017, 03:28:35 pmOoops. Well of course I meant triac. Sorry!I need to admit, I had to read between the lines of the engrish that google spit out, so if it says replacing the triac did not change anything: Same here :/

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 04, 2017, 03:51:59 pm
content: Quote from: wraper on November 04, 2017, 03:45:06 pmI could not find any useful information on how the i-Tool works internally. I checked the contacting of the front connector and also measured the tip temperature with a digital tip thermometer while heating up. Displayed values until Error 8 match with the control measurements, so temperature readout seems OK, as does the heating.Curiously the error occurs on all heat settings hi/mid/lo and on all set temperatures. It does not matter if I set 250°C or 450°C - the error occurs when reaching / coming close to the target temperature.

author: wraper
author_rank: Unknown
timestamp: November 04, 2017, 04:13:53 pm
content: I have one I-con 2 which rarely shows error 8 on 1st channel. Usually before this there is very high incorrect temperature displayed. I just checked, communication with i-tool is purely digital. Also when you disconnect i-tool while working, 999 temperature is displayed. So this may be an error in communication, it stops reading the temperature and throws out an error.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 04, 2017, 04:43:50 pm
content: Thanks wraper for your input so far!I guess I will have to try with another heating cartridge and another i-Tool to rule out some variables. Also I am going to give Ersa a call to assess if the described behavior somehow is a known issue. Will keep you posted when something turns up.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 07, 2017, 08:36:14 pm
content: I talked to Ersa support and afterwards to someone from a long time distributor for Ersa about the issue.Ersa said I will have to change the main PCB (that part is available for »only« 188,20€ + tax!!).The technician from the company selling Ersa gear told me, that they ran into similar problems and only changing the main board sorted it out. Even though they are in business as the main distributor for Ersa (for more than two decades) in this part of Germany, they could not get their hands on servicing instructions or schematics to simply fix the main board instead of switching out the whole assembly.We had a nice talk and I got some information about what they already tried to investigate, but had to let go because of lack of time and staff to dedicate for such adventures.I got some pointers on things to try. Seems like I will be on a reverse engineering mission for the next couple of weekends...

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 07, 2017, 10:22:31 pm
content: Turns out that I am not a very attentive reader :/Coreires postin another Ersa repair thread already had all the answers, but I was blind and couldn't see the wood for the trees.Just like coreire wrote, the 5V regulator is also the culprit on this i-Con. I checked with my FLIR and the regulator gets warm fast. Then, the i-Con throws Error 8. If I provide additional cooling to the voltage regulator, the i-Tool keeps heating up and works just fine.The regulator is an LM1086CT-5.0 and has a smallish FK252 heat sink piggy-backed. There is not even thermal compound involved and the FK252 is only 21K/W.I will replace the LM with a new part tomorrow and attach a bigger heat sink to extend its live expectancy.

author: wraper
author_rank: Unknown
timestamp: November 07, 2017, 11:22:06 pm
content: Quote from: frozenfrogz on November 07, 2017, 10:22:31 pmIndeed, because of following:QuoteNo he didn't. And he have not repaired the fault, just mitigated the consequences.QuoteNo it wasn't and it's clearly written in his post. The issue was not in LM1086 and replacing it did not fix it. He was fighting with consequences not cause by adding a fan. There was increased current consumption somewhere else. He added the fan so mitigated the issue but hasn't repaired the root cause. LM1086 is linear regulator and does not overheat by itself, if it overheats, something in it's load is not fine. you should find what causes increased current consumption, not change working parts.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 07, 2017, 11:54:56 pm
content: The voltage regulator I pulled from the board has an internal short between the adjust pin and V_out pin. I am not all to familiar with the LM1086, but that definitely does not look right. I guess the LM has been damaged due to lack of cooling and the internal short circuit now drives it into thermal overload auto-shutdown.I will put in a new part and check if there is excessive current draw - but right now, I doubt that.BTW: I will have to check the bypass capacitor also. Maybe it is failing and the voltage regulator is driven into self-oscillation.

author: wraper
author_rank: Unknown
timestamp: November 08, 2017, 12:18:20 am
content: QuoteDid you measure actual voltage which was on it's output? There is no ADJ pin, it's 5V version and is has GND pin instead. If there was short between output and GND, there would be 0V on the output.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: November 08, 2017, 06:46:50 pm
content: I think I solved it!Since I could not identify a part that was getting to hot with my thermal camera, I took another approach backwards, measuring the resistors and transistors and heating them up with the hot air station. Turns out, there was a blown resistor!Next to the big cap, there is an SMD resistor with 2.2k ohm, marked 222. Case dimensions are 5mm x 2mm, so 5025 metric / 2010 imperial. I do not exactly know what it does, but I guess it has got something to do with current sense/current limiting.From the case dimensions my guess is the resistor should be 0.5W - 1W. I need to buy some proper replacement tomorrow, but for testing purposes I soldered in a 2.2k, 0.5W metal-film resistor.The i-Tool heats up, goes to standby after set time and wakes up when moving - no more Error message!Thanks wraper for all the input and pointers. I was to sleepy yesterday to draw the right conclusions from measuring the voltage regulator. After thinking about it I might have accidentally set the multimeter to diode testing mode instead of resistance, thinking the LM was shorted between GND/ADJ and VOut.The original regulator should still be OK (changed it already and added a bigger heat sink).