24Vac soldering iron on DC?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Probably not.

I can't find the basestation for this iron, but usually you set the temperature on the basestation. This means that there's some interaction between the iron and the basestation, i.e. there are more than two wires.

Have you thought about gas? I have a gas iron from Maplin that I like a lot, unfortunately now discontinued.

This one is on offer at the moment, but I can't recommend it purely because I haven't tried it:- Solderpro 70 Gas Soldering Iron Kit : Gas Soldering Irons Kits : Maplin

w
 
Administrator
Joined 2004
Paid Member
Hi Paul, pdul,
Check that!
Since a soldering iron is simply a resistive heater, it will work equally well on AC or DC.
Sure, the heating element is, but the switch in a Weller will fail quickly when run on DC. Some irons use a triac to control the heating element as well (having repaired more than just a few).

Hi Boscoe,
Have a good look a the iron and the plug end. Can you supply pictures of both the plug and iron complete please?

Many of the Asian irons do run on DC, and they use a type of proportional / bang-bang control for the element temperature control. There are units I really like with the brand name of "Solomon". They kill Weller and Ungar products for performance and reliability, and they sell for less than $100 CDN here. That's with a fully variable temperature control and digital display (with real numbers even). There is a tempt set setting, and a tip temperature monitor setting. I calibrated mine. :)

My comment about reliability comes from owning and maintaining about 20 stations. Weller wasn't the worst of them, but they were anything but reliable. That darn switch assy cost enough! My Solomon is now over 16 years old, then it finally had a problem. I found the manufacturer, and they sent me a schematic for it!!!! It's now working perfectly again (now I've jinxed it). The iron connector was another failure point on the Weller stations, and > $120 a crack, no way!

If you plan on working on anything with ICs and small transistors, get the controlled temp station with ground. There are various tips for these (Solomon), so you're laughing. My fav. is the largest screwdriver tip. Marvelous for surface mount, and old radios both. If anything, they are cheap to own and use.

The thing to watch for on other irons is AC leakage currents. The inexpensive non-station irons are terrible for that. The Butane irons that wakibaki mentioned wouldn't suffer from that, but static from you is a possible problem. It can be with any iron, but at least the stations have a connection to ground where you can drain that energy. I always touch the metal chassis or ground point first.

-Chris
 
Is the iron having two wires, then you can use 24 volts.
If the iron has four wires, then you cannot use 24 volts continueously.

I have a 24 volts weller temperature controlled iron without the controller. Connecting 12 volts to it, it is enough for small soldering jobs.

If you have a variable DC power supply, then you can try at what voltage the iron is hot enough.

Gajanan Phadte
 
Administrator
Joined 2004
Paid Member
Hi Tom, pdul,
Lucky as heck is all I can say!
I built my own base part to replace a dead Weller one. This one has performed much better than the units with the original base. It has some extra series resistance in line with the iron. The proper Weller base unit supplies 24 VAC to the iron, that I can tell you. Switch contacts have much lower DC ratings than they do AC ratings, so if your iron lasts 23 years, that switch may have been good for 100 years running on AC. Of course, your running hours are what is important here. My iron saw 18 hour days.

I do own a 12 VDC Weller temperature controlled iron. It looks close to the same idea as the WPTCN types I have, but the heater is probably different. Since I haven't had any trouble with it yet, I have not torn it down. The normal stations are another story all together! I do have one that lasted a long, long time and eventually failed. The most common failure points with these are the switch (#1 fault), the connector (#2 - cheap, why did they use it to begin with??) and the actual heating element (#3). The last type of part I needed to stock were barrel nuts and tips. We went through tips like crazy, normal service shop use. I had the earlier ones too, they did not have plugs. These were the skinny ones, and were much better as far as I was concerned.

Remember, I had more than 15 of these things on the go, plus or minus (the numbers varied over time, 20 was the max). When I changed to the "Solomon" brand, it was a major improvement. It had much less variance in tip temperature for one. Tips lasted decades, not months. These have electronic control, not switch control. The only reason mine went down was due to old capacitors. Replacing those brought it back to new condition. I have a spare iron assembly for it (unused as yet), and it uses a DIN connector that is far more reliable than the cheap thing Weller supplied. I did buy another one of these for backup too. It's still in it's box, and I can't find the darn thing. Anyway, that was to come into use if this original iron suffers a major failure, like the transformer or horribly burnt PCB.

-Chris
 
Official Court Jester
Joined 2003
Paid Member
Anatech , I'm using Solomon for last 5-6 years ;
it's around 50W ( I'm rarely looking what's written on base of handle ) , 24Vac one - bought it as semi kit - bare electronic ( which I put in base of previous 24Vac station) and iron itself ;

control electronic is probably some local made jobbie , because markings on control chip are removed :rofl: , probably for exlusivity sake

that first Iron last some 4,5 years , mostly working 12hr/day , sometimes I just forgot to power it down during night etc.

using two different tips for different jobs ( in fact now I'm using two different Irons - simpler to change them than to change tips) I'm wasting those two tips per year .

completely agree with your comparison with weller - I have same experience .

anyway - can you treat me with that schematic ?

who knows when I'll need it

:cheers:
 
Administrator
Joined 2004
Paid Member
Hi Paul,
The contact life depends on the waveform it is interrupting. With AC, any arc is extinguished at a rate of twice the applied frequency. Also, the make or break may occur at any random point in the waveform. That means a zero crossing is as likely as a peak when you open or close the contacts.

Believe me, it does make an enormous difference to the contacts if they are switching a DC current, or an AC current. The heating coil has almost nothing to do with this.

-Chris
 
Administrator
Joined 2004
Paid Member
Hi wakibaki,
If you take the time to research this iron as I did:
I did. I see you finally did as well. :)
you will see that it is NOT a Weller type but has it's temperature set on the base station.
Well, yes. However, I was addressing comments made by other members at that point in time. There was an incorrect comment made that needed to be corrected.
This means that it is NOT suitable for operation from batteries, which is what the OP asked.
Yes. We have come back to the OP's question. Never mind that the hot air portion may use an AC motor, and it certainly does use a high power heater. That's probably triac controlled as a guess. I have a different make of hot air station and would never consider trying to run it from DC.

I used the example of a Weller station simply because most members would be used to that. The concept would be easier to explain that way.

Interestingly, the Solomon would probably run fine from a DC source.

Hi dazed2,
Buy the Solomon. It's not perfect, but it's more perfect than many out there. Mine has run for many years, to the point where the caps failed. It's now running perfectly again. Tips tend to last a long, long time, and there is a good selection of them. It's so much better than the Weller stations - and cheaper, so there should be no worries with reliability. Besides, the same exact model has been made for over 15 years now.

Hi Prodanovic,
No problem, and my pleasure. The parts in mine still have their numbers, and where standard parts at the time. I wonder if the newest irons have a newer metering chip set?

I'll send it tomorrow. PM me if you have a different email address, otherwise I'll use what I had the last time.

-Chris :)
 
Official Court Jester
Joined 2003
Paid Member
.......

Hi Prodanovic,
No problem, and my pleasure. The parts in mine still have their numbers, and where standard parts at the time. I wonder if the newest irons have a newer metering chip set?

I'll send it tomorrow. PM me if you have a different email address, otherwise I'll use what I had the last time.

-Chris :)

just for the record ( now I'm typing from my workshop ) my trusty Solomon is SL-I , 24V/48W ; I reckon - if there is 5-pin DIN , good chance is that circ is pretty similar , if not the same electrically .

use >sasnojunkica5 at gmail dot com< ; oldest one is acting funny sometimes

TIA
 
Last edited by a moderator:
Hi Paul, pdul,
Check that!

Sure, the heating element is, but the switch in a Weller will fail quickly when run on DC.
-Chris

I ran a Weller WTCP iron for about 15 years off a 24volt DC switchmode (universal supply - I wanted something I could country hop without worrying about mains coltage) and had no trouble with the switch units whatsoever - burned up a couple of elephants but no switches. Then I discovered Metcal....soldering nirvana!.
M
 
Administrator
Joined 2004
Paid Member
Hi Prodanovic,
YGM on your old account. Should I resend? ... I resent and adjusted your post to avoid spam.

Hi mobyd,
The WTCP was the skinny one, wasn't it? If so, I had very few problems with those except a few burned their transformer out.

All I can say is that you're lucky. Any switch contacts will pit, erode and foul much more quickly on DC. I wonder if they reduced the contact current rating when they went to the WTCPN? I know that once I had to change a switch, many would follow in the same iron. Yes, I moved the ceramic capacitor over (arc suppression). This is the only reason why I know so much about the Weller products, they caused me much pain.

After checking, the Solomon stations run the heater on AC and use a triac for the switching. I'm pretty sure that you could fit a triac inside the Weller irons and use the switch for gate current only. I may do that with the last Weller I have. Otherwise I'll just throw it out once it fails again.

-Chris
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.