TS100 doesn't function properly when earthed

[technogeeky]

Ugh, that brick is nasty inside, I think they forgot that they needed to include space for the input side reservoir capacitor!

I actually use one of these to power an Agilent spectrum analyzer. Perhaps unwisely. Hah. My favorite part is the brand name for these is Minger which is slang (in the UK) for an unattractive woman.

[MacMeter]

Here are some quick tests I did with a BM235 DMM.
TS100, with version 2.02 Ralim’s GitHub open source firmware.
Mean Well 24 voltS DC, 90 watt, switching power supply with ground plug.
Iron plugged in, but not powered on to heat. *Heating up the iron did not effect voltage readings.

TIP to EARTH GROUND = 14 volts AC. * Power supply GROUNDED
TIP to EARTH GROUND = 58 volts AC. * Power supply UNGROUNDED (used a 3-2 ground lift)

Using supplied TS100 ground clip from units ground screw to earth ground: VOLTAGE = ZERO

Last test was in response to the original poster.
I observed the irons on screen behavior while placing and removing the ground clip wire from iron to earth ground.
Temp set to 650F, while UNGROUNDED, iron reaches set temp and stabilizes.

With iron earth GROUNED, the temperature hovers around set temp, but is JUMPY, can see quick jumps up to 675F. The onscreen HEATER ICON, is indicating iron is constantly heating/cooling. As soon as earth GROUND is REMOVED, unit behaves normally again, temp stabilizes, heater icon stays OFF.

I have not tested the supplied firmware. I’ll pass this on to the open source firmware author.

[Rooster Cogburn]

Here are some quick tests I did with a BM235 DMM.
TS100, with version 2.02 Ralim’s GitHub open source firmware.
Mean Well 24 voltS DC, 90 watt, switching power supply with ground plug.
Iron plugged in, but not powered on to heat. *Heating up the iron did not effect voltage readings.

TIP to EARTH GROUND = 14 volts AC. * Power supply GROUNDED
TIP to EARTH GROUND = 58 volts AC. * Power supply UNGROUNDED (used a 3-2 ground lift)

Using supplied TS100 ground clip from units ground screw to earth ground: VOLTAGE = ZERO

Last test was in response to the original poster.
I observed the irons on screen behavior while placing and removing the ground clip wire from iron to earth ground.
Temp set to 650F, while UNGROUNDED, iron reaches set temp and stabilizes.

With iron earth GROUNED, the temperature hovers around set temp, but is JUMPY, can see quick jumps up to 675F. The onscreen HEATER ICON, is indicating iron is constantly heating/cooling. As soon as earth GROUND is REMOVED, unit behaves normally again, temp stabilizes, heater icon stays OFF.

I have not tested the supplied firmware. I’ll pass this on to the open source firmware author.

That's very interesting. Seems like the Mean Well PSU uses ground to dissipate some of the AC leakage, but does not directly die DC negative out to ground.

I tried a few versions of Ralim's firmware, none of them work reliably. Temperature rises smoothly to the set one and then just randomly jumps around, regardless of the grounding situation. With the the stock firmware it's stable, unless I ground the tip without grounding the PSU.

I also posted on the Mini forums:

http://www.minidso.com/forum.php?mod=viewthread&tid=3132&extra=page%3D1

You could also report your findings there. There seems to be a problem with temperature sensing + hard grounding.

[MacMeter]

Here are some quick tests I did with a BM235 DMM.
TS100, with version 2.02 Ralim’s GitHub open source firmware.
Mean Well 24 voltS DC, 90 watt, switching power supply with ground plug.
Iron plugged in, but not powered on to heat. *Heating up the iron did not effect voltage readings.

TIP to EARTH GROUND = 14 volts AC. * Power supply GROUNDED
TIP to EARTH GROUND = 58 volts AC. * Power supply UNGROUNDED (used a 3-2 ground lift)

Using supplied TS100 ground clip from units ground screw to earth ground: VOLTAGE = ZERO

Last test was in response to the original poster.
I observed the irons on screen behavior while placing and removing the ground clip wire from iron to earth ground.
Temp set to 650F, while UNGROUNDED, iron reaches set temp and stabilizes.

With iron earth GROUNED, the temperature hovers around set temp, but is JUMPY, can see quick jumps up to 675F. The onscreen HEATER ICON, is indicating iron is constantly heating/cooling. As soon as earth GROUND is REMOVED, unit behaves normally again, temp stabilizes, heater icon stays OFF.

I have not tested the supplied firmware. I’ll pass this on to the open source firmware author.

That's very interesting. Seems like the Mean Well PSU uses ground to dissipate some of the AC leakage, but does not directly die DC negative out to ground.

I tried a few versions of Ralim's firmware, none of them work reliably. Temperature rises smoothly to the set one and then just randomly jumps around, regardless of the grounding situation. With the the stock firmware it's stable, unless I ground the tip without grounding the PSU.

I also posted on the Mini forums:

http://www.minidso.com/forum.php?mod=viewthread&tid=3132&extra=page%3D1

You could also report your findings there. There seems to be a problem with temperature sensing + hard grounding.

If you haven’t tried the 2.02 version open source, give it a try. I’ve tried the later releases, and had the same issues you did, and always ended up reflashing back to the older version which works as expected. The GitHub crew is continuing work on newer versions, and since it’s easy to flash, I’ll continue to experiment with them.

[Rooster Cogburn]

If you haven’t tried the 2.02 version open source, give it a try. I’ve tried the later releases, and had the same issues you did, and always ended up reflashing back to the older version which works as expected. The GitHub crew is continuing work on newer versions, and since it’s easy to flash, I’ll continue to experiment with them.

I tried that firmware (just checked again) and it doesn't work at all for me. Temperature rises but after 2-3 seconds the firmware just crashes with the heating element permanently on. Seems to happen  every time

I got a new PSU today. 20V 3.5A Dell laptop brick, grounded, 9EUR with shipping on eBay. Seems to work great! I once had the iron reset like the power dropouts I frequently had with the crap power brick, but could not repeat it afterwards in over an hour of playing around with the iron.

Too bad I did not get any feedback / reply on the Mini forums. It seems the grounding issue might be more widespread since you also have it, but I'm a bit concerned that really none of the Ralim firmware releases seem to work on my TS100. Hope I didn't get a defective unit.

[MacMeter]

If you haven’t tried the 2.02 version open source, give it a try. I’ve tried the later releases, and had the same issues you did, and always ended up reflashing back to the older version which works as expected. The GitHub crew is continuing work on newer versions, and since it’s easy to flash, I’ll continue to experiment with them.

I tried that firmware (just checked again) and it doesn't work at all for me. Temperature rises but after 2-3 seconds the firmware just crashes with the heating element permanently on. Seems to happen  every time


I got a new PSU today. 20V 3.5A Dell laptop brick, grounded, 9EUR with shipping on eBay. Seems to work great! I once had the iron reset like the power dropouts I frequently had with the crap power brick, but could not repeat it afterwards in over an hour of playing around with the iron.

Too bad I did not get any feedback / reply on the Mini forums. It seems the grounding issue might be more widespread since you also have it, but I'm a bit concerned that really none of the Ralim firmware releases seem to work on my TS100. Hope I didn't get a defective unit.

That’s odd, I had some issues since I was flashing back and forth. If you can get it not to crash, what I’ve done is to first use the RESET function, then change all the settings to my liking, like Fahrenheit etc. Sometimes a power reboot helps. But if it’s crashing, then I don’t know what to add. If you are so inclined you could join the GitHub project to get feedback. Have not seen any reports of the firmware crashing, I’m assuming when you flash you can see the message that the firmware was successful, the main project page has more info on flashing on different platforms. I’m using a Mac laptop with no problems.

[Rooster Cogburn]

That’s odd, I had some issues since I was flashing back and forth. If you can get it not to crash, what I’ve done is to first use the RESET function, then change all the settings to my liking, like Fahrenheit etc. Sometimes a power reboot helps. But if it’s crashing, then I don’t know what to add. If you are so inclined you could join the GitHub project to get feedback. Have not seen any reports of the firmware crashing, I’m assuming when you flash you can see the message that the firmware was successful, the main project page has more info on flashing on different platforms. I’m using a Mac laptop with no problems.

I'm also using a Mac and I get the .RDY file indicating a successful update. The tip with resetting the settings first is a good one, maybe that was the issue. Basically, the iron boots up, but as soon as I enter solder mode I get like 2-3s of rising temperatures and then the display freezes and the heater is kept on. I would've reported a bug, but that was only with the older firmware and the newer one does not show this behavior. Probably not useful reporting it since it has apparently been fixed.

But your success story with a particular firmware encourage me to try some more, and it seems the latest RC fixes the issue(s) for me! I have so far only tried the actual releases, but just tried 'V2.04 Release Candidate 2' (latest as of right now). I spend half an hour de & re-soldering random components on junk boards and it seems to work just fine. No temperature fluctuations, no freezes. The boost mode is quite neat and the temperature display seems more responsive than with the official firmware. Neat!

[MacMeter]

That’s odd, I had some issues since I was flashing back and forth. If you can get it not to crash, what I’ve done is to first use the RESET function, then change all the settings to my liking, like Fahrenheit etc. Sometimes a power reboot helps. But if it’s crashing, then I don’t know what to add. If you are so inclined you could join the GitHub project to get feedback. Have not seen any reports of the firmware crashing, I’m assuming when you flash you can see the message that the firmware was successful, the main project page has more info on flashing on different platforms. I’m using a Mac laptop with no problems.

I'm also using a Mac and I get the .RDY file indicating a successful update. The tip with resetting the settings first is a good one, maybe that was the issue. Basically, the iron boots up, but as soon as I enter solder mode I get like 2-3s of rising temperatures and then the display freezes and the heater is kept on. I would've reported a bug, but that was only with the older firmware and the newer one does not show this behavior. Probably not useful reporting it since it has apparently been fixed.

But your success story with a particular firmware encourage me to try some more, and it seems the latest RC fixes the issue(s) for me! I have so far only tried the actual releases, but just tried 'V2.04 Release Candidate 2' (latest as of right now). I spend half an hour de & re-soldering random components on junk boards and it seems to work just fine. No temperature fluctuations, no freezes. The boost mode is quite neat and the temperature display seems more responsive than with the official firmware. Neat!

Glad you got it working. Boost feature is great, as well as the time out settings. I’ll play with 2.04 when it’s final, as all the versions since 2.02 I’ve tried had minor issues for me. One of the issues these firmware writers are dealing with, is there are now two different hardware versions, seems some internal parts have changed. This has added some complexity but it’s claimed they are accounting for this in their firmware. From what I remember, the info screen can show something like “PB1” for the original hardware, or “PB2”, for the newer version. On firmware 2.02, I don’t get that screen, but when playing with the newer firmware at one point, I could access that info screen, and that’s how I know mine is the older hardware version. Not that it should matter according to the firmware author.

I’m assuming no matter what firmware is used, stock, or open source, the temperature fluctuations are still an issue, and I sent that info to the author, have yet to hear back, maybe no one has tested or seen this before? Since as of now I’m not doing any board soldering, so I’ll be using mine “ungrounded”. And if I ever need to ground, I don’t think the small temp jumping will stop me from being able to melt the solder, but’s it’s GOOD to know!

[Rooster Cogburn]

Glad you got it working. Boost feature is great, as well as the time out settings. I’ll play with 2.04 when it’s final, as all the versions since 2.02 I’ve tried had minor issues for me. One of the issues these firmware writers are dealing with, is there are now two different hardware versions, seems some internal parts have changed. This has added some complexity but it’s claimed they are accounting for this in their firmware. From what I remember, the info screen can show something like “PB1” for the original hardware, or “PB2”, for the newer version. On firmware 2.02, I don’t get that screen, but when playing with the newer firmware at one point, I could access that info screen, and that’s how I know mine is the older hardware version. Not that it should matter according to the firmware author.

I'd be interested to know if I got the first or second revision. Where exactly in which firmware is that board revision supposed to show up?

I’m assuming no matter what firmware is used, stock, or open source, the temperature fluctuations are still an issue, and I sent that info to the author, have yet to hear back, maybe no one has tested or seen this before? Since as of now I’m not doing any board soldering, so I’ll be using mine “ungrounded”. And if I ever need to ground, I don’t think the small temp jumping will stop me from being able to melt the solder, but’s it’s GOOD to know!

It seems there are two issues, perhaps related.

With the stock firmware, the temperature fluctuations are clearly related to grounding / PSU AC leakage. I made a post on Mini's forum to make them aware of these findings, maybe there's something they can do in firmware or future hardware revisions.

With the Ralim firmware, it seems there's another issue. Even if I remove any earth connection or use the earthed PSU + earthed tip setup that works with the stock firmware, I have quite significant temperature fluctuations once the target temperature has been reached. There's a bug report on GitHub with many users confirming this problem.

For me, tying the DC- out of my power supply to ground did bring down the tip to mains earth potential to ~1.5VAC, you could probably quite easily do that with your setup without having to modify your cable to add an earth wire. I'm currently using a three wire cable with my new earthed power supply, but I'll replace that with a two wire cable. It's a bit heavy and it's not easy finding a silicone (flexible + burn proof) cable that's thin. With the two wire one I'll connect DC- to both the ground screw and the DC plug, giving me the same full earthing with only two wires.

[Gyro]

That’s odd, I had some issues since I was flashing back and forth. If you can get it not to crash, what I’ve done is to first use the RESET function, then change all the settings to my liking, like Fahrenheit etc. Sometimes a power reboot helps. But if it’s crashing, then I don’t know what to add. If you are so inclined you could join the GitHub project to get feedback. Have not seen any reports of the firmware crashing, I’m assuming when you flash you can see the message that the firmware was successful, the main project page has more info on flashing on different platforms. I’m using a Mac laptop with no problems.

I'm also using a Mac and I get the .RDY file indicating a successful update. The tip with resetting the settings first is a good one, maybe that was the issue. Basically, the iron boots up, but as soon as I enter solder mode I get like 2-3s of rising temperatures and then the display freezes and the heater is kept on. I would've reported a bug, but that was only with the older firmware and the newer one does not show this behavior. Probably not useful reporting it since it has apparently been fixed.

But your success story with a particular firmware encourage me to try some more, and it seems the latest RC fixes the issue(s) for me! I have so far only tried the actual releases, but just tried 'V2.04 Release Candidate 2' (latest as of right now). I spend half an hour de & re-soldering random components on junk boards and it seems to work just fine. No temperature fluctuations, no freezes. The boost mode is quite neat and the temperature display seems more responsive than with the official firmware. Neat!

Ah, progress indeed. A good deal on the brick too - it's hard to beat a main brand one, even if it is second hand (and dirt cheap!)

The reason you had no success with the Ralim older firmware is that (not surprisingly I suppose) you have the newer version of the iron - my older one works fine with it. The two versions were originally thought to be the same electrically but it was found that MiniDSO had changed the accelerometer IC (the original was discontinued it think). The change of I2C caused f/w problems.

Keep an eye on the V2.04 release candidates, Ben is working hard to optimize the temperature performance (stability) with different tip sizes. I don't think he's far from an official V2.04 now.

[Specmaster]

I also had a look at the TS100 when I was looking for a new iron setup, but instead settled for the T12 system and judging by the reports in this thread, I'm glad I did. There is no way that an iron after 2 weeks should fail and require to have the mosfets replaced at customers expense and that high leakage to the tip is also not desirable. I can report that the T12 does not have those issues, albeit the earthing on the metal case is not effective and I had to remedy it on both of my stations but the tip was suitably earthed however.

What me decide on the T12 over the TS100 was partly the high asking price for the TS100 but also the fact that there was in my opinion, problems on the horizon with the interface between power and the iron itself. I hope that it works OK for you now.

[Rooster Cogburn]

Ah, progress indeed. A good deal on the brick too - it's hard to beat a main brand one, even if it is second hand (and dirt cheap!)

I wanted to buy one at the flea market, but it had to rain that weekend Well, 9EUR is perfectly fine. The laptop charger was a good suggestion, they're a dirt cheap source of grounded, reliable PSUs. 20V vs 24V does not seem to make a difference, still getting exactly 11s for ambient - 300C.

The reason you had no success with the Ralim older firmware is that (not surprisingly I suppose) you have the newer version of the iron - my older one works fine with it. The two versions were originally thought to be the same electrically but it was found that MiniDSO had changed the accelerometer IC (the original was discontinued it think). The change of I2C caused f/w problems.

Keep an eye on the V2.04 release candidates, Ben is working hard to optimize the temperature performance (stability) with different tip sizes. I don't think he's far from an official V2.04 now.

Ok, that does explain it. I'll keep watching for the final 2.04 release!

I also had a look at the TS100 when I was looking for a new iron setup, but instead settled for the T12 system and judging by the reports in this thread, I'm glad I did. There is no way that an iron after 2 weeks should fail and require to have the mosfets replaced at customers expense and that high leakage to the tip is also not desirable. I can report that the T12 does not have those issues, albeit the earthing on the metal case is not effective and I had to remedy it on both of my stations but the tip was suitably earthed however.

What me decide on the T12 over the TS100 was partly the high asking price for the TS100 but also the fact that there was in my opinion, problems on the horizon with the interface between power and the iron itself. I hope that it works OK for you now.

At <20EUR the T12 stations do seem appealing:

https://de.aliexpress.com/item/MINI-T12-OLED-soldering-station-electronic-welding-iron-2017-New-design-DC-Version-Portable-T12-Digital/32839523934.html

Especially if you don't need the portability aspect of the TS100 (I don't). Hakko tip compatibility also seems good.

I don't mind the earthing situation on the TS100 in general, having a ground screw terminal would be sufficient for me. Problem is the design issue with the glitchy temperature display caused by removing the PSU AC leakage through the aforementioned ground screw.

If I understand correctly, the MOSFET failures are a combination of the TS100 not having any overcurrent protection and the tip being faulty. I hope by being diligent and testing the tip resistance of newly purchased tips I can avoid this fate with my iron, but it would of course be unfortunate if tips would fail with a short and then cause damage to the MOSFET. We'll see.

One thing that turned me off the TS12 was the amount of different models. I think I'd have chosen a model without internal PSU, as I couldn't be certain of the quality and it would be easier to supply a known-good one myself. Then I'd have to add a ground terminal to the station myself. Also the included handles seemed of sketchy quality and replacing them is made more difficult by each TS12 variant using a different connector.

[MacMeter]

I also had a look at the TS100 when I was looking for a new iron setup, but instead settled for the T12 system and judging by the reports in this thread, I'm glad I did. There is no way that an iron after 2 weeks should fail and require to have the mosfets replaced at customers expense and that high leakage to the tip is also not desirable. I can report that the T12 does not have those issues, albeit the earthing on the metal case is not effective and I had to remedy it on both of my stations but the tip was suitably earthed however.

What me decide on the T12 over the TS100 was partly the high asking price for the TS100 but also the fact that there was in my opinion, problems on the horizon with the interface between power and the iron itself. I hope that it works OK for you now.

The mosfet failed due to a dead short in his tip, that he neglected to test prior to using. Not sure if that would happen on your setup. Glad you are happy with your purchase, I looked at those. I would not discount the TS100 as a very useful product, they have been out for sometime with many satisfied users, including myself. Now if I had to rely on soldering boards for a hobby or living, I’d buy the new Pace station for about $250 US. If you have followed the Pace thread, you will see there are some early issues with those tips, granted it’s a brand new product and will be worked out. I’m no fanboy of any products or brands as they all have their own issues.

This thread was started by Rooster, to help in diagnosing an odd issue he discovered where the temperature on the display would be jumpy, when the iron was grounded to earth. While I don’t have the need right now to ground my iron, it does interest me, and perhaps a few others. I can still solder while grounded if need be, and the temp jumping 10-20 degrees is not a huge issue to me in my needs. There are at least 3-4 other threads on this forum debating the pluses and minuses of the TS100, let’s attempt to keep this thread on topic, which is trouble shooting a single issue.

[Specmaster]

There a lot of versions of the T12 and I see this as a good thing because people are always constantly trying to improve it and also of course, it means that its a popular choice so therefore plenty of support for it.

I went for a pre-built version https://de.aliexpress.com/item/2017-STC-T12-Digital-Soldering-Iron-Station-Temperature-Controller-EU-Plug-Temperature-180-450-Degrees-T12/32803295956.html?spm=a2g0s.9042311.0.0.PXMaON (set 5) as my first option and then discovered that I was the first person it seemed to go this particular maker and was advised to look at others which I did with whats known as the Blue controller which I used to build another station up from. I used the following parts in its build https://de.aliexpress.com/item/QUICKO-Neue-Ankunft-T12-Stromversorgung-24-V-108-Watt-4-5A-f-r-OLED-LED-l/32834572016.html?spm=a2g0s.9042311.0.0.PXMaON this the same psu as the ready made unit and is rock solid. Enclosure was https://de.aliexpress.com/item/SUHAN-injected-mold-table-box-enclosure-case-Alumium-alloy-shell-for-Digital-soldering-station-DIY-kits/32821952541.html?spm=a2g0s.9042311.0.0.PXMaON, handle was https://de.aliexpress.com/item/Modified-FX-9501-Handle-For-T12-Oled-Digital-Display-Soldering-Station-Silicone-Line-Handle-DIY/32735591205.html?spm=a2g0s.9042311.0.0.PXMaON (I modded this to use 4 pin plug to match controller) and this was the controller https://www.banggood.com/T12-Digital-Soldering-Station-OLED-Display-Control-Board-STC-Controller-Kit-p-1140746.html?rmmds=myorder&cur_warehouse=CN which I found had a bug in its setup that could allow the tip glow red hot, so this was replaced with this https://de.aliexpress.com/item/OLED-T12-solder-iron-DIY-kits-Unit-QUICKO-Soldering-Iron-Station-parts-Temperature-Controller-T12-952Meatal/32825705805.html?spm=a2g0s.9042311.0.0.PXMaON (set 1) and so far they have been brilliant.

[Gyro]

This thread was started by Rooster, to help in diagnosing an odd issue he discovered where the temperature on the display would be jumpy, when the iron was grounded to earth. While I don’t have the need right now to ground my iron, it does interest me, and perhaps a few others. I can still solder while grounded if need be, and the temp jumping 10-20 degrees is not a huge issue to me in my needs. There are at least 3-4 other threads on this forum debating the pluses and minuses of the TS100, let’s attempt to keep this thread on topic, which is trouble shooting a single issue.

^^^ What he said.

[Specmaster]

This thread was started by Rooster, to help in diagnosing an odd issue he discovered where the temperature on the display would be jumpy, when the iron was grounded to earth. While I don’t have the need right now to ground my iron, it does interest me, and perhaps a few others. I can still solder while grounded if need be, and the temp jumping 10-20 degrees is not a huge issue to me in my needs. There are at least 3-4 other threads on this forum debating the pluses and minuses of the TS100, let’s attempt to keep this thread on topic, which is trouble shooting a single issue.

^^^ What he said.

Yeh, sorry guys, I wasn't hijacking the thread at all, just a quick comment about how I almost became a TS100 owner and now, I'm glad I didn't buy one.

[MacMeter]

This thread was started by Rooster, to help in diagnosing an odd issue he discovered where the temperature on the display would be jumpy, when the iron was grounded to earth. While I don’t have the need right now to ground my iron, it does interest me, and perhaps a few others. I can still solder while grounded if need be, and the temp jumping 10-20 degrees is not a huge issue to me in my needs. There are at least 3-4 other threads on this forum debating the pluses and minuses of the TS100, let’s attempt to keep this thread on topic, which is trouble shooting a single issue.

^^^ What he said.

Yeh, sorry guys, I wasn't hijacking the thread at all, just a quick comment about how I almost became a TS100 owner and now, I'm glad I didn't buy one.

Your detailed info would be very useful in the proper place. Like many I was overwhelmed with all the choices in creating a T12 station, wish I had seen your research beforehand. I’m not big on all the cheap Chinese site offerings, and it can be difficult to sort through the good and bad. Granted, the TS100 is Chinese made, but it’s been out for awhile, and well reviewed by many smarter then me. The kit I bought even included a 20 volt PSU, so it’s a much simpler purchase at a low cost. Wish you much luck with your purchase, and if you ever need a mobile solder solution, give the TS100 a 2nd look.

[Rooster Cogburn]

I got my 2-core flexible & burn-resistant silicone cable today and build this:



If you got an earthed power supply this has the same VAC / resistance to mains earth than the three wire solution and allows for a thinner & lighter cable.

The current RC of the Ralim custom firmware is also working nicely for me.

Thanks again everybody for your input!

[MacMeter]

I got my 2-core flexible & burn-resistant silicone cable today and build this:



If you got an earthed power supply this has the same VAC / resistance to mains earth than the three wire solution and allows for a thinner & lighter cable.

The current RC of the Ralim custom firmware is also working nicely for me.

Thanks again everybody for your input!

Did the latest firmware solve the temperature fluctuations when earth grounded?

[Rooster Cogburn]

Did the latest firmware solve the temperature fluctuations when earth grounded?

I can't check with the old crappy, floating PSU since I sent it back to Amazon. But I just hooked it up to my bench PSU (which is also not earthed and has some AC leakage) and the effect seems to be a lot smaller vs the official firmware. The temperature fluctuates by +/- 5C instead of the otherwise smaller 1-2C after attaching a ground clip. So it still has some effect but it's not unusable like with the official firmware. Interesting!

[KL27x]

If you guys are just going off what the display reads, it might be less of a problem than you think.

Measuring with a tip tester might be more pertinent.

Simply using the iron is perhaps another way to see if it is working ok.

To even get a stable-appearing reading is an illusion that depends on taking the reading at the right time and averaging them. The heater is flicking on/off very quickly when the tip is near set temp, and the heater and sensor are much closer to each other than the sensor is to the tip. The millisecond to millisecond true reading on the sensor will easily vary by many degrees when the temp at the tip is perfectly stable.  So I suppose it is possible that this issue just might be more esthetics and the iron just might be working pretty close to the way an iron should.

[MacMeter]

If you guys are just going off what the display reads, it might be less of a problem than you think.

Measuring with a tip tester might be more pertinent.l

Simply using the iron is perhaps another way to see if it is working ok.

To even get a stable-appearing reading is an illusion that depends on taking the reading at the right time and averaging them. The heater is flicking on/off very quickly when the tip is near set temp, and the heater and sensor are much closer to each other than the sensor is to the tip. The millisecond to millisecond true reading on the sensor will easily vary by many degrees when the temp at the tip is perfectly stable.  So I suppose it is possible that this issue just might be more esthetics and the iron just might be working pretty close to the way an iron should.

I’ve done accurate tip temp testing, (a different thread). Very accurate. The flickering reading we are discussing here, is only seen when the iron is earth grounded, on mine the heater icon keeps showing its heating up constantly. None if this happens when the earth ground is removed. The display is rock steady and accurate in that case.

[Rooster Cogburn]

If you guys are just going off what the display reads, it might be less of a problem than you think.

Measuring with a tip tester might be more pertinent.

Simply using the iron is perhaps another way to see if it is working ok.

To even get a stable-appearing reading is an illusion that depends on taking the reading at the right time and averaging them. The heater is flicking on/off very quickly when the tip is near set temp, and the heater and sensor are much closer to each other than the sensor is to the tip. The millisecond to millisecond true reading on the sensor will easily vary by many degrees when the temp at the tip is perfectly stable.  So I suppose it is possible that this issue just might be more esthetics and the iron just might be working pretty close to the way an iron should.

Fair enough, the actual tip temperature is probably very much a huge low-pass filter over the temperature readouts. Still, there seems to be some effect on the temperature reading when draining the PSU's AC leakage current through the ground screw. It's probably best avoided, even if it's just the readout jumping up & down 50C or whatever. Thankfully that's easy to do.

btw, unrelated, but I just had to file another bug for the current RC of Ralim's firmware. Seems like the sleep mode doesn't work for me. The temperature doesn't got down properly and sometimes the TS100 gets a blank screen if left in sleep while this not-so-correctly-working sleep mode happens. Did another ~2h of soldering today and it appears to be working beautifully during normal operation, though.

[KL27x]

To expound, I have made an adjustable power iron controller using a very small tip with integrated heater. For the PWM cycle, I went with something like 3 Hz. I could have just as easily done 10's of kHz, but I just don't see it making a difference in the end. I rather know I'm getting ever so slightly more heat into the tip and less into the MOSFET via switching losses. The tip was is relatively high power to thermal mass - warm up of like 6ish seconds - and I never noticed the oscillation. So even if the thing is glitching, as long as it averages out and is not changing the set point or calibration, you might not be able to notice any practical difference... when you're soldering, at least.

[MacMeter]

If you guys are just going off what the display reads, it might be less of a problem than you think.

Measuring with a tip tester might be more pertinent.

Simply using the iron is perhaps another way to see if it is working ok.

To even get a stable-appearing reading is an illusion that depends on taking the reading at the right time and averaging them. The heater is flicking on/off very quickly when the tip is near set temp, and the heater and sensor are much closer to each other than the sensor is to the tip. The millisecond to millisecond true reading on the sensor will easily vary by many degrees when the temp at the tip is perfectly stable.  So I suppose it is possible that this issue just might be more esthetics and the iron just might be working pretty close to the way an iron should.

Fair enough, the actual tip temperature is probably very much a huge low-pass filter over the temperature readouts. Still, there seems to be some effect on the temperature reading when draining the PSU's AC leakage current through the ground screw. It's probably best avoided, even if it's just the readout jumping up & down 50C or whatever. Thankfully that's easy to do.

btw, unrelated, but I just had to file another bug for the current RC of Ralim's firmware. Seems like the sleep mode doesn't work for me. The temperature doesn't got down properly and sometimes the TS100 gets a blank screen if left in sleep while this not-so-correctly-working sleep mode happens. Did another ~2h of soldering today and it appears to be working beautifully during normal operation, though.

The sleep issue is why I went back to the older firmware 2.02. No issues with that version, other then temp jumping and heater constant on (ONLY when earth grounded). Since as of now, I’m not doing anything electronics sensitive, and solder ungrounded.