Author Topic: Mini TS100 soldering iron and current leakage  (Read 20532 times)

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Offline bodgerTopic starter

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Mini TS100 soldering iron and current leakage
« on: June 24, 2017, 12:10:56 pm »
I recently brought myself a Mini TS100 soldering iron (Sainsmart branded) came with a switch mode power supply like those found on laptops. I noticed that while the iron was cold but still powered that if I ran my finger against the tip I'd feel a slight 'tingle'. So I measured the AC voltage at the tip against ground and found it to be around 115V, I'm guessing this is not uncommon for an iron that isn't grounded?

I'm about to put together a class AB audio amp (just for kicks), but wanted to know if this leakage (is that the correct term?) could potentially damage components such as the amp ic, capacitors, resistors, etc. I'd also be interested to know what causes a SMPS to pass this 'leak' through, the technically term would be nice to know so I could research it.

This is my first post, so apologies if I haven't followed correct forum etiquette. Thanks in advance.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #1 on: June 25, 2017, 11:52:18 am »
welcome to the world of switching psu's with a capacitor coupling the secondary to the input earth - that often does not exist but is then capacitivly coupled to the input terminals!!

this bullshit extends to devices like settop-boxes & tv's btw.
 

Offline voltsandjolts

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Re: Mini TS100 soldering iron and current leakage
« Reply #2 on: June 25, 2017, 01:00:39 pm »
Don't put up with that BS. Return the iron to the seller and tell them it is a POS.
Then buy a better iron with earthed tip. A lot of folks here recommned hakko's (see EEVBlog video).
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #3 on: June 25, 2017, 01:24:25 pm »
Don't put up with that BS. Return the iron to the seller and tell them it is a POS.
Then buy a better iron with earthed tip. A lot of folks here recommned hakko's (see EEVBlog video).

you obviously know nothing about the product - it's a battery powered iron.
the issue is with the psu - and the "problem" is incredibly common.

it would be better to use a linear psu with a nice toroidal transformer, a rectifier and a cap.
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #4 on: June 25, 2017, 03:29:07 pm »
Thanks for the replies. I'll probably just ground the iron via a 1Mohm resistor or construct a 4S lipo battery (just a pain they used a 5.5mm x 2.5mm connector, have a few 2.1mm laying about). Hakkos are overpriced by around 33% when compared to US prices here in England, I needed something portable and for £50 the Mini TS100 is excellent value and performs as good as the Wellers I used at college and I find it easier to work with the pencil style irons.
I've noticed the "problem" with metal constructed laptops in the past too, just surprised none of the Mini TS100 reviews I looked into mentioned the possible effect of using a SMPS.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #5 on: June 25, 2017, 03:34:34 pm »
does the psu have an earth pin?
you could mod it so it's actually grounded.
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #6 on: June 25, 2017, 03:38:05 pm »
No earth pin unfortunately, it's got one of those figure 8 cables (C7 I think is the official cable name)
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #7 on: June 25, 2017, 05:18:29 pm »
those things  :--
they could have atleast used a 3pin "clover-leaf" type.
 

Offline voltsandjolts

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Re: Mini TS100 soldering iron and current leakage
« Reply #8 on: June 25, 2017, 06:10:41 pm »
Don't put up with that BS. Return the iron to the seller and tell them it is a POS.
Then buy a better iron with earthed tip. A lot of folks here recommned hakko's (see EEVBlog video).

you obviously know nothing about the product - it's a battery powered iron.
the issue is with the psu - and the "problem" is incredibly common.

it would be better to use a linear psu with a nice toroidal transformer, a rectifier and a cap.

Optionally battery powered. As I understand it the OP was making measurements with the mains SMPS plugged into the iron, which is a valid use case. In that situation, when applying solder you are making a conducting path between your hand and the soldering tip. That tip is separated from 240VAC mains by the supplied chinese SMPS. If you are happy to trust your life to that go right ahead. I notice the manual suggests connecting a separate (optional!) earth wire which you should certainly do if using it with the supplied mains SMPS connected. Consider getting a UL listed quality SMPS if you are keeping this iron and using it with the SMPS connected.
 

Online Simon

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Re: Mini TS100 soldering iron and current leakage
« Reply #9 on: June 25, 2017, 07:15:33 pm »
Is the SMPS earthed ? this sounds very much like a lack of earth connection. many SMPS will have an input filter that puts two capacitors in series across the mains with the centre ping earthed, if there is no earth there will the 1/2 the mains supply voltage there, if the iron is then "earthed" you will have a problem.
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #10 on: June 25, 2017, 07:36:45 pm »
Is the SMPS earthed ? this sounds very much like a lack of earth connection. many SMPS will have an input filter that puts two capacitors in series across the mains with the centre ping earthed, if there is no earth there will the 1/2 the mains supply voltage there, if the iron is then "earthed" you will have a problem.

No it isn't earthed, but my old Dell laptop power supply which is earthed has a similar effect. Having done a little more research it looks like this is an effect of the Y-caps, which are pretty much required in SMPSs to pass EMI radiation tests.
 

Online Simon

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Re: Mini TS100 soldering iron and current leakage
« Reply #11 on: June 25, 2017, 07:38:29 pm »
Yes I was referring to the Y caps, if you have other equipment doing this it means you don't have an earth in your house.
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #12 on: June 25, 2017, 08:07:11 pm »
Yes I was referring to the Y caps, if you have other equipment doing this it means you don't have an earth in your house.

I made an assumption about the Dell power supply as most of the new ones I have are grounded, the one I tested wasn't grounded plus it had what appeared to be a clover socket, turned out to be a unnecessarily large figure 8 socket. Make sense that my newer laptop power supplies don't exhibit the same problem. Thanks.
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #13 on: June 25, 2017, 09:11:53 pm »
No it isn't earthed, but my old Dell laptop power supply which is earthed has a similar effect. Having done a little more research it looks like this is an effect of the Y-caps, which are pretty much required in SMPSs to pass EMI radiation tests.
Means that there was no earth connected in your mains sockets.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #14 on: June 28, 2017, 10:15:00 am »
I feel like the dunce in the corner for asking this. But if there's no earth connection for the iron... or if there is an earth connection but it isn't plugged into anything, then how does the 115V potential get to the tip of the iron? Is not the tip electrically isolated from the heating element in every soldering iron?

I built an iron ran from ungrounded laptop supply, and I had zero issues. The earth pin for the handpiece, I just left unconnected.
« Last Edit: June 28, 2017, 10:20:41 am by KL27x »
 

Offline MosherIV

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Re: Mini TS100 soldering iron and current leakage
« Reply #15 on: June 28, 2017, 10:17:39 am »
Quote
I feel like the dunce in the corner for asking this. But if there's no earth connection for the iron... or if there is an earth connection but it isn't plugged into the SMPS, then how does the 115V potential get to the tip of the iron?

stj said :
Quote
welcome to the world of switching psu's with a capacitor coupling the secondary to the input earth - that often does not exist but is then capacitivly coupled to the input terminals!!
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #16 on: June 28, 2017, 10:20:22 am »
Ok, I feel like an even bigger idiot for asking, then. Cuz I still don't get it.

If I take the "tingly" TS100 and I put a layer of micarta or ceramic or kapton tape over it, then put another sheet of metal over that... I can still measure 115 V between that and earth?

Quote
capacitivly coupled to the input terminals
Why would the input terminals be in continuity with the tip of the iron?
« Last Edit: June 28, 2017, 10:21:58 am by KL27x »
 

Offline 3db

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Re: Mini TS100 soldering iron and current leakage
« Reply #17 on: June 28, 2017, 10:23:19 am »
This iron actually has an earthing screw on top above the power connector.

3DB.




 

Offline MosherIV

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Re: Mini TS100 soldering iron and current leakage
« Reply #18 on: June 28, 2017, 10:27:25 am »
Quote
If I take the "tingly" TS100 and I put a layer of micarta or ceramic or kapton tape over it, then put another sheet of metal over that.
You have just created another capacitor.

If you put AC on one side/plate of the capacitor, the other plate will become charged.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #19 on: June 28, 2017, 10:34:00 am »
^But inductive AC ripple wouldn't create 115VDC potential to earth, would it? Wouldn't it be just.. plus and minus xV from earth (or whatever you were measuring it against?) The capacitor would block DC.

Quote
This iron actually has an earthing screw on top above the power connector.
This makes sense to me (but maybe I'm an idiot). So perhaps the earthing screw is connected to a wire in the cable? Or to a shield in the cable which eventually runs to the sheath of the T12 style tip? In this case, you could snip the connection and install a switch to select grounded vs floating tip?

Also, since it runs off DC, perhaps the designers assume that the DC ground will be grounded to earth IF/WHEN the unit is run off an actual grounded smps? So perhaps even in the hand piece itself, the 3 connections of the tip, 2 of them are shorted together? So it might even require modification to the iron internals, itself, to liberate the sheath from any connection?

Or if the fit of the tip in the handpiece is loose enough, you could maybe wrap the base of the sheath/tip in kapton tape, so only the 2 heater/thermocouple connections are exposed? Jam that back into the handpiece, and shazam, you have an isolated tip? :)

I don't have T12 iron, but I would assume if you equate it with a TRS stereo plug, the base ring is the tip/earth and the middle and tip rings are to the heater/thermocouple unit.
« Last Edit: June 28, 2017, 10:50:26 am by KL27x »
 

Offline MosherIV

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Re: Mini TS100 soldering iron and current leakage
« Reply #20 on: June 28, 2017, 10:49:21 am »
Quote
But inductive AC ripple wouldn't create 115VDC potential to earth, would it?
Quote
Also, since it runs off DC, perhaps the designers assume that the DC ground will be grounded to earth
The problem here is that the SMPS designers have not grounded the 0V/common so if floats.
The 0V can be pushed up to anything between Earth/0V to the full mains voltage by capacitive coupling.

Yes, grounding the tip will work but do not do it while the SMPS is on.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #21 on: June 28, 2017, 11:00:25 am »
^Ok, I get that. But does the tip/earth connection of the T12 tip have to be connected to anything?

 I have read that the heater and thermocouple are in series. Is it like a JBC where there is a center tap between the heater and the sensor, making 3 connectors in total? And the tip is in continuity with one of them at all times?  I only count 3 connectors on the T12 tip, and it runs off AC in the Hakko FX950/1, so it means DC control circuit and earth have to be the same, and in direct continuity with the tip? Or is there a fourth connector hidden in the very end of the tip?

I have some T12 tips coming, and I was planning on the tip to be
1. tip/earth
2. heater
3.cathode of thermocouple

And you run the power between 2 and 3. Turn it off and read the voltage between 2 and 3. The resistance of the heater doesn't matter, it just adds a little variable impedance which you are going to prolly swamp anyway with the opamp circuit resistors.

*Also, you are wrong and I am right about the other example of wrapping the tape around the iron and wrapping that in foil?
« Last Edit: June 28, 2017, 11:08:22 am by KL27x »
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #22 on: June 28, 2017, 11:14:18 am »
Ok, I'm betting there is a fourth connector in the base of the tip. It doesn't make any sense for the tip to be in continuity with any of the heating/sensing elements.

If this is the case, all you have to do is disconnect the sheath from DC ground. Problem solved.
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #23 on: June 28, 2017, 01:04:56 pm »
^But inductive AC ripple wouldn't create 115VDC potential to earth, would it?

It's 115Vrms AC that I was measuring on the tip, as I understand it the y-cap causes a small current to float at half mains voltage.
 

Offline 3db

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Re: Mini TS100 soldering iron and current leakage
« Reply #24 on: June 28, 2017, 01:48:48 pm »
I just did a quick measurement of the resistance between the earth screw and the tip. It's approx 0.9 - 1 ohms.
I used a Fluke 101,so nothing fancy.

3DB.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #25 on: June 28, 2017, 02:03:17 pm »
the real answer is to open the psu and replace the 2pin inlet with a 3pin one.
re-case it if you have to.
or go on ebay and get a chinese metal-frame 24v 6a+ psu

also the iron should really be earthed through a 1meg resistor incase of earth faults in the building.
it will let the iron disipate static etc, but will limit the current to a safe level if anything bad happens.
« Last Edit: June 28, 2017, 02:06:03 pm by stj »
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #26 on: June 28, 2017, 02:12:59 pm »
is it this?
https://www.sainsmart.com/pro-32-digital-oled-programable-soldering-iron-station-embedded-interface-dc-5525.htm

they are saying 40w?

the iron can pull 70w at 24v.
so either the psu is under voltage, or under-rated, or they are just full of shit!

what's the spec printed on the psu?
their wiki says "With 19V 2A power supply, SainSmart Pro32 takes only about 11 seconds to heat up to 300 degrees."
is that what they are supplying??
« Last Edit: June 28, 2017, 02:20:46 pm by stj »
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #27 on: June 28, 2017, 02:24:37 pm »
also the iron should really be earthed through a 1meg resistor incase of earth faults in the building.
it will let the iron disipate static etc, but will limit the current to a safe level if anything bad happens.
All grounded equipment is always connected directly to the earth. Including tips of all ESD safe soldering stations. No 1M resistors there. If there is the earth fault, there will be much worse problems in your house as your PC, fridge, washing machine and most of other equipment is directly connected to it too.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #28 on: June 28, 2017, 02:46:47 pm »
my old weller DS80 used a limiting resistor - it's in the schematics.
also, Hakko 888D has the option by moving a pin on the iron connector.
(with / without resistor)
 

Offline bodgerTopic starter

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Re: Mini TS100 soldering iron and current leakage
« Reply #29 on: June 28, 2017, 03:09:38 pm »
is it this?
https://www.sainsmart.com/pro-32-digital-oled-programable-soldering-iron-station-embedded-interface-dc-5525.htm

they are saying 40w?

the iron can pull 70w at 24v.
so either the psu is under voltage, or under-rated, or they are just full of shit!

what's the spec printed on the psu?
their wiki says "With 19V 2A power supply, SainSmart Pro32 takes only about 11 seconds to heat up to 300 degrees."
is that what they are supplying??

Yes that's the one (link is broken now). They supply it with a 19V power supply, but it can operate between 12-24V (they claim 17W to 65W, which is accurate you will get 65W @ 24V) typically these irons do not come with a PSU (Sainsmart has just decided to supply one, with an EU socket). They are fairly accurate with the heating time, I timed it at around 12sec with the 19V supply against the temperature sensor on my extech using a k-type sensor and it hit roughly 300degC.
The iron itself is fine, they should have been a bit more wiser and supplied it with a grounded PSU. Other than that I'm pretty happy with it.
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #30 on: June 28, 2017, 03:47:21 pm »
my old weller DS80 used a limiting resistor - it's in the schematics.
DS80 is not a soldering station. If you mean WSD 80 or WS 80, there is no resistor.
Quote
also, Hakko 888D has the option by moving a pin on the iron connector.
(with / without resistor)
Option? You mean modding the iron and loosing warranty?
Quote
Power consumption   65W (26V)
Tip to ground resistance   <2ohm
Tip to ground potential   <2mV
Heating element   Ceramic heater
Standard tip   Shape-B (No.T18-B)
Cord length   1.2m
Total length   217mm (with B tip)
Weight   46g (with B tip)
« Last Edit: June 28, 2017, 03:52:14 pm by wraper »
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #31 on: June 28, 2017, 05:57:17 pm »
DS80 is an 80w desoldering station.
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #32 on: June 28, 2017, 06:32:27 pm »
DS80 is an 80w desoldering station.
It's desoldering iron/tool, not station. It must be connected to the soldering station in the first place.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #33 on: June 28, 2017, 06:36:28 pm »
Confirmed, i am an idiot. So problem is AC ripple of 115V. I saw "leak" in title and it was late and i imagined high impedance dc potential.

So if you say wanted to add a ground to your smps, could u "just" change the figure 8 connector (and cord) to the 3 prong kind and then connect that wire from earth to the negative of the dc output? Or do you have to do something to the Y caps, too?

I say "just" because the connector would have to physically fit just right.

Perhaps there's an opportunity for a kit for this type of problem that wouldnt risk voiding UL cert or rause firemarshall/insurer eyebrow.  You get a small black box with a Dell 3 prong cord. Out of the black box you get a very short pigtail figure 8 AC cord and a lone 4mm socket for a ground connection where u can earth stuff? Label to show maximum amps of the cord?

Can this sell like snowcones in july?

I ask this because it is ok to connect a banana plug fly wire to dc side of the output cable yourself, is it not? As long as the smps black box remains sealed and unaltered, is good? (Also, besides insurance concerns, most SMPS are in a case that is ultrasonically welded. So there is no way to close it back up that looks nice). So I imagine if you could make this "kit" people would buy it. Perhaps instead of a pigtail figure 8 cord, it would just have the connector extending out the side, so you can plug it into end end of any SMPS and leave it there, perhaps even glue the two together, effectively changing it from 2 plug AC input to 3 plug grounded.



« Last Edit: June 28, 2017, 07:25:42 pm by KL27x »
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #34 on: June 28, 2017, 06:52:23 pm »
Also fwiw, i never measured ac ripple on my unearthed 19v zd99 diy iron, but i used it for a year without ever killing a component. But if op can feel a tingle, i wouod say there is problem!

I have measured ac ripple on my hakko 888 after putting 1 Mohm between tip and earth and it is a fraction of a volt.

(I understand this makes the iron less safe in event u solder to live circuit, if this makes it no longer "ESD safe" i am fine with the common use of the terminology; i have no qualm soldering laser diode with this 1 Mohm earth connection... but i dont know if a 1Mohm earth would be sufficient to bring a 115v ripple down to essentially nothing).
« Last Edit: June 28, 2017, 07:04:44 pm by KL27x »
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #35 on: June 28, 2017, 07:15:58 pm »
DS80 is an 80w desoldering station.
It's desoldering iron/tool, not station. It must be connected to the soldering station in the first place.

no, it's a station - like the soldering stations but with an internal pump.
DONT MAKE ME TAKE PHOTO'S OF IT!!
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #36 on: June 28, 2017, 07:38:34 pm »
^ This is very interesting. But I wonder @wraper, who cares if is it soldering tool or desoldering tool? What's the difference? Does desoldering tool NOT need to be "esd safe?"

I think the hakko 1 Mohm resistor thing is also something curious. Why would they put a resistor between an unused pin and ground? I supposed there are markets where they prefer 1Mohm connection to earth on this station. Or perhaps they leave it to their customers. I have no concern opening a hakko and/or voiding the warranty, though. In Europe this would be a horror, I suppose, where the Hakko stations are expensive and rare. Over here, they are pretty cheap. And if I thought I'd ever need a warranty on them, I wouldn't be buying them. I'd be buying the Chinese clones in the first place.
« Last Edit: June 28, 2017, 07:40:37 pm by KL27x »
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #37 on: June 28, 2017, 07:40:58 pm »
DS80 is an 80w desoldering station.
It's desoldering iron/tool, not station. It must be connected to the soldering station in the first place.

no, it's a station - like the soldering stations but with an internal pump.
DONT MAKE ME TAKE PHOTO'S OF IT!!
Really?
http://www2.produktinfo.conrad.com/datenblaetter/825000-849999/831816-an-01-en-Entloet_Set.pdf
« Last Edit: June 28, 2017, 07:45:50 pm by wraper »
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #38 on: June 28, 2017, 07:51:49 pm »
^ This is very interesting. But I wonder @wraper, who cares if is it soldering tool or desoldering tool? What's the difference? Does desoldering tool NOT need to be "esd safe?"
He made a claim there is a resistor in such station. But such soldering station does not exist in the first place, which makes such claim very dubious. Also I have not seen any weller tool with a resistor on GND inside. Moreover I haven't seen a single soldering station with the tip connected through resistor and not directly to the earth.
 

Offline DimitriP

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Re: Mini TS100 soldering iron and current leakage
« Reply #39 on: June 28, 2017, 08:10:06 pm »
Quote
the iron should really be earthed through a 1meg resistor

All / Any "grounded" irons specify some 2-5 Ohms from tip to ground.
No way you can get that "through"  a 1M resistor.

Well...OK...except the TS100 that ships with the wrong power supply
   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #40 on: June 28, 2017, 08:22:30 pm »
BTW I have TS100. Tip is not connected to PSU GND, only to grounding screw. However there is 100n capacitance between PSU and the tip, which easily allows AC leaking from PSU to the tip.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #41 on: June 28, 2017, 09:13:23 pm »
Yes, the design of t12 tip looks like it could make a good capacitor.

I agree essentially all "esd safe" irons i have seen are earthed directly. 8n some case that might be necessary to stop the the AC ripple. In all cases it makes the iron safer to use in case of contact of tip with live voltage rail. Only the project may be damaged over the user being electrocuted.

But it there are many irons that have a floating tip. And people use these for esd sensitive components without any problem. Radio shack 2 prong firebrand got many hobbyists by for years. If  floating it good nuff, 1 mohm is better. For t12 iron on a shoddy smps, floating isnt good enough, so 1 mohm might not be good enough, either. But if u add 3 prong, u can presumably ground the dc return directly and remove the problem, despite the tip remains floating or attached thru 1 mohm. Or direct, if that is your preference for personal safety issue. If working on mains and lower voltage, i am gonna be fine with floating tip. If circuit is mistakenly live, the handle of the iron will insulate me. And perhaps i still manage to notice the circuit is live before i kill myself. Rather than 90 percent chance i blow up my project and blackout my lights, lab equipment, and computer.

Maybe if u use earthed iron this is another reason to put the iron on the joint first, before touching the solderwire to it. So u trip the circuit breaker before testing the joint with your left arm tingle detector. ;)
« Last Edit: June 28, 2017, 09:43:58 pm by KL27x »
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #42 on: June 28, 2017, 09:27:25 pm »
the DS80 is not a digital station, it's older than your poster.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #43 on: June 28, 2017, 09:37:30 pm »
Cool. Maybe it was made before the we became so sue happy. And people had personal resposibility. I believe you, stj.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #44 on: June 28, 2017, 09:41:23 pm »
Since so many people viewing this thread have t12 iron, can someone tell me how many connectors are on a t12 tip? My clone tios are on a slow boat from china and i need to work out the drive circuit.
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #45 on: June 28, 2017, 09:49:56 pm »
the DS80 is not a digital station, it's older than your poster.
Of course it's not digital as it's just a soldering iron without electronics inside. It's up to the user to which compatible station attach it to.
EDIT: if you said DS800, DS600 or DS100, I would believe you. But I don't believe weller made iron and station of exactly the same model.
« Last Edit: June 28, 2017, 09:59:35 pm by wraper »
 

Offline 3db

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Re: Mini TS100 soldering iron and current leakage
« Reply #46 on: June 29, 2017, 01:23:16 pm »
Who cares ?    :=\
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #47 on: June 29, 2017, 04:01:10 pm »
pix
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #48 on: June 29, 2017, 04:14:12 pm »
Since so many people viewing this thread have t12 iron, can someone tell me how many connectors are on a t12 tip? My clone tios are on a slow boat from china and i need to work out the drive circuit.

you mean the actual cartridges, or the plug on the iron cable?
different handles have differnt plugs.

cartridge pinouts in this:
« Last Edit: June 29, 2017, 04:27:34 pm by stj »
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #49 on: June 29, 2017, 04:57:55 pm »
pix
So... Why you repeatedly claimed it is DS 80 when it's not?
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #50 on: June 29, 2017, 05:03:28 pm »
BTW I don't see claimed resistor on the schematic on it's front panel.




 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #51 on: June 29, 2017, 05:46:55 pm »
that's just a sketch - post a photo of the base pcb.
 

Online wraper

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Re: Mini TS100 soldering iron and current leakage
« Reply #52 on: June 29, 2017, 06:10:42 pm »
that's just a sketch - post a photo of the base pcb.
Whaat? Burden of proof is on the claiming side (you claimed there is a resistor). Where should I get that outdated station in the first place, LOL? Have you even measured a resistance between the earth connection and the tip?
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #53 on: June 29, 2017, 08:07:18 pm »
yes, i did.
it had a resistor and rifa capacitor in parallel FYI.

still, it's history now - those are on my parts shelf with no electronics in them.
i was thinking of fitting a digital controller and ssr in them to use a newer iron assembly.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #54 on: June 29, 2017, 08:18:43 pm »
@stj thx for the link. That helps. If im reading it right, there are only 3 connections on the cartridge, then. And the ts100 only uses 2 or them, no connection the to tip/sheath. So no hidden metal contact on the very back end of the cartridge?
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #55 on: June 29, 2017, 09:35:47 pm »
i think the ts100 does link the shaft of the cartridge to the earth screw and probably the input-jack.

btw, if your going to build a controller then you may as well build that one - it's the simplest i'v seen.
you can skip the gyro chip to make it even simpler.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #56 on: June 29, 2017, 09:41:26 pm »
yes, lower-right of the schem.
j1 coupled to main ground via c26.

interesting. it wont pass dc, so no accidental discharging of big caps while soldering!!  >:D
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #57 on: June 29, 2017, 10:12:10 pm »
Well i am not much good at this, but it looks like A and B are connections to either end of what would be the heater. If u look at the cartridge, u will see two ring contacts at the end away from the working tip. I assume these are A and B. And the rest of the cartridge metallic surface that includes the tip wouod be what should be earthed in an ESD safe iron according to IPCS or however u spell/acronym?

J1 at the bottom right shows a capacitor btn PGND and B. Which i am confused because B doesnt seem to be the tip, and capacitor wouldnt earth it even if pgnd was earthed.
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #58 on: June 29, 2017, 10:22:18 pm »
So my understanding is perhaps not full, here. I might have to shelve my controller dev until my T12 handpiece and tips get here.

The way I am guessing is that power is applied through A and B ring contacts, then cut, then a TC output of uV can be measured between A and B. But this implies that you can send several amps through the TC without damaging it, and I don't even know if that is possible. I don't know what the voltage drop and resistance of a TC is nor if you can do that without damaging it. In theory it's just two different metals welded together, so it seems like it should be possible to just use it as a conductor when not reading it.

A > heater wire > TC > B           ???

If my idea works, my Hakko 888 will be able to drive a T12 tip with up to 17% more power than an actual Hakko 951. And 70% more power than a DC laptop supply clone at nominal 20VDC max (without even including the pauses for reads needed in the DC version).
« Last Edit: June 29, 2017, 10:37:09 pm by KL27x »
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #59 on: June 29, 2017, 10:32:47 pm »
o.k. i was a bit wrong.
the cartridge is earthed, the wrist-strap is decoupled through a cap.

your operational theory is right, the thermocouple is in series.
you power the element, then cut the power & read the voltage on the same pins.
then if it's under the set temp - power it up again.

this is the place it all comes from.
http://minidso.com/forum.php?mod=forumdisplay&fid=67

 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #60 on: June 29, 2017, 10:41:06 pm »
Awesome, thanks!

I love your WS801 chassis, BTW. Should be able to make a nice bit of kit with it. I was considering buying an old Hakko on eBay to use for something similar. But it will be so much easier to hack an 888, if I manage to get it right. I plan to use the existing 888 interface and display for setting the temp, and my micro will just figure out where the 888 is set at by spoofing the 888's ADC and figuring out where it it trying to turn on the heater. Of course with a flip of a switch, it will be a regular 888.
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #61 on: June 29, 2017, 10:48:35 pm »
not WS, DS - it still has a big pump in it!  8)
 

Offline stj

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Re: Mini TS100 soldering iron and current leakage
« Reply #62 on: June 29, 2017, 10:53:19 pm »
I plan to use the existing 888 interface and display for setting the temp,

i wouldnt,
scrap the electronics and start fresh.
the 888d's weak point is the interface.
and maybe use something like this!!
http://www.ebay.co.uk/itm/0-95-Inch-SPI-OLED-Display-Module-Full-Color-65K-Color-SSD1331-7-Pin-For-Arduin-/292115525887
 

Offline KL27x

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Re: Mini TS100 soldering iron and current leakage
« Reply #63 on: June 29, 2017, 11:10:45 pm »
^true, the 888 interface is lamo. A better interface is phase 2, cuz that is a boring job.

What the 888 has going for it is a 26V torque beast hemi engine stuffed into the smallest box possible, comes with a really nice handpiece in itself, and Fry's likes to give them away for pennies every 4 months. I picked up a couple at the last sale, and first order of business is to unleash the beast.

 

Offline shinji2009

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Re: Mini TS100 soldering iron and current leakage
« Reply #64 on: September 03, 2019, 02:09:34 am »
hi.  can anybody please  tell what resistance must be from rings (contacts) of a tip to its body? i got two tips for ts-100 today and one shows megaohms and other gust 100 ohms so i wonder if one of them faulty and maybe i shouldn't use it.
 

Offline Gyro

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Re: Mini TS100 soldering iron and current leakage
« Reply #65 on: September 03, 2019, 03:41:20 pm »
Hi,

The only continuity you should normally see is between the two ring contacts. The one with continuity between the rings and the body sounds faulty / dodgy (I'm not sure if anyone makes fake TS100 tips as it is a limited market).

Personally, I wouldn't use it and would contact the supplier.


P.S. The resistance of insulation always gets worse with temperature, so if it is measuring 100R at room temperature then it could be considerably worse at soldering temperature.
« Last Edit: September 03, 2019, 03:48:24 pm by Gyro »
Best Regards, Chris
 


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