Modification to a ZD-987 desoldering/soldering station using a external switching power supply

[sam_sam_sam]

I have been working on this concept for quite some time now with limited success but recently I found a switching power supply that is setup for the voltage that this soldering station needs to operate at however it also needs part of the secondary circuit from the original switching power because you need several voltage rails

I once tried to get a ZD-915 desoldering station to work on a 18 volt battery power supply but unfortunately things did not go well but I did find a work around but I might try this idea again but going at a little differently more about this another time

I talk about doing this in another post which I will link it to this post

I did this at first as a proof of concept and was not sure if it was going to work with out issues but it does work and better than I expected it to

Here is the switching power supply that I used for this project

https://www.ebay.com/itm/164440680270?var=464055952719. 18 volt @ 20 amp switching power supply

I now have to wire up the switching power supply to the on/off switch and to the input outlet on the soldering station system so that the switching power supply is controlled the way it was originally designed to do but with a better made switching power supply

Here is where I started the this conversation about weather or not the switching power supply would be the right choice

https://www.badcaps.net/forum/troubl...8-volts-20-amp

[sam_sam_sam]

If I have time this weekend to work on the switching power supply enclosure more to come later

[sam_sam_sam]

Well I turned on the soldering iron side today to test a soldering iron that I had on the bench and I could not remember why it was there at first but then I remembered why it was there because one of them the tip almost to far gone on one side of it which is weird but this was not caught my attention what did catch my attention was when the iron came up to working temperature the switching power supply fan would speed up when it was calling for heating and when it was not calling for heating it slowed down to almost nothing these very well built switching power supply from what I have seen so far

[stj]

thats good, most fans just use a thermister but tracking the current stops it heating to begin with

[sam_sam_sam]

thats good, most fans just use a thermister but tracking the current stops it heating to begin with

I would agree with you and like said earlier in this post that I think that this switching power supply seems to be well built but they had Chinese made capacitors that got replaced with brand name capacitors

[sam_sam_sam]

I might get the switching power supply enclosure done tomorrow but we will see if I have enough time to devote to it or not

[sam_sam_sam]

I do not have time to work on unfortunately partly because of the weather and I some things that I to finish up today

[sam_sam_sam]

Well I had some time today to work on the switching power supply enclosure I hooked up the DC power supply and now I have to finish the outlet side of the switching power supply to the soldering/desoldering station some pictures to later when I have incoming power supply hooked up and just before I put all of the covers back on and torcher test all put together

[sam_sam_sam]

Well this project is almost done all I have to do now is put the cover on the enclosure and put it all together and the last picture is the desoldering/soldering station is set up and ready to go

This project took a little while to do because of the challenging part that I had to figure out how I was going to put everything together and make it look professional which is the main problem yea I know could have it together but I know how that turns out in the long run

I tried again to power this on battery power and the mosfet gets very warm very fast so it was not an error that I did the first time I have to set it up like I talked about in a post a long time ago but sense I was messing around with this again I thought I would try it again just for my curiosity and this has bothered me for a while and I had to put it to rest once for all

[sam_sam_sam]

Now I have to modify the other desoldering/soldering station this version does not have the sleep function this is the reason I did the other one first because it does have have the sleep function on it then I several hot air gun/soldering iron station but I have to figure out how I going set them up because I do not use the hot air gun very often but these two have the sleep function on the soldering iron part so I going to change it to the version that does not have the sleep function because I will probably used this unit when I have to use the hot air gun

[sam_sam_sam]

I going to try to recap the other 18 volt @ 20 amp switching power supply and modify the secondary power supply board of the original switching power and get this one up and running soon I hope so that I have two of these soldering/desoldering stations up and running ( with two different size tips for the iron and for the gun )

Then work on the battery operated version with the setup that I talked about in another post a while back and finally complete this project once and for all ( The plan is to use one of my other soldering iron controllers that has the sleep function for the battery operated soldering iron )

[sam_sam_sam]

Unfortunately I was not able to get recapping this switching power supply because of more important things came up hopefully I can get to not this coming up weekend but the following weekend I hope I can get this finished and and get it back up and running again

[sam_sam_sam]

Well I had some time today and got the small value capacitors done on second switching power supply but unfortunately I do not have any brand name 3300uf @ 35 volt capacitors output supply rail I have to order some for these switching power supply boards I do not very many high UF value capacitors on hand in my capacitor bins case I order them as I need them because of cost per capacitor

I should order some 1500 , 2200 and 3300 @ 25 and 35 volt ones if the diameter are different or the height is different I quite a few low voltage ones like 6.3 , 10 and some 16 volt one of those values but by doing this the order will probably about or over $65.00 plus shipping unless I want to wait three weeks to a month and order them from Taiwan like I did for the low value capacitors bought recently I checked what this eBay seller has in the higher UF values and they have very limited range of higher UF values

So I going to place an order with Dig-key probably next month sometime and finish the recapping of both switching power supplies

One note I did use the soldering / desoldering station that has the sleep function on with the new switching power supply and it works perfectly fine no issues

[sam_sam_sam]

I had to work yesterday and have not had time to do anything to it I might find time today to maybe get something done to switching power supply enclosure so it can be mounted in the external enclosure and wire it up and modify the soldering station switching power supply secondary so it can work with the new switching power supply

[Agent24]

Interesting project, why the external power supply at all, though? Battery power I can understand but don't these already have a PSU inbuilt?

[sam_sam_sam]

Interesting project, why the external power supply at all, though? Battery power I can understand but don't these already have a PSU inbuilt?

To answer your question about why using an external switching power supply is because the switching power is not of a good quality and after many hours of use it tends to have a higher rate of failure that I have not figured out exactly what the fault is but sometimes it is a switching power supply regulator failure and sometimes when you replace the switching power supply regulator it fails again or it just refuses to turn on again

Plus the original switching power supply is underrated for the amount of current that it sometimes needs to provide when you first turn it on and I have also had the switching power supply transformer failure as well plus the size of the switching supply board plus the switching supply transformer are small compared to the switching power supply that I replaced it with

Like I mentioned earlier when you convert it to battery power you have to add a PWM controller and a 3D mosfet controller board as well because you do not have any control for the mosfet was was originally used on the switching power supply board

[Agent24]

Ah, I'm glad then that my ZhongDi hot air and soldering station is an older model and uses a linear power supply.

[sam_sam_sam]

Ah, I'm glad then that my ZhongDi hot air and soldering station is an older model and uses a linear power supply.

If yours has a linear power supply you need to look at this board where the bridge rectifier and filtering capacitors are and make sure that the soldering joints are in good shape because there are issues with these boards with bad soldering joints and then the traces burn up and then you have power supply issues

[sam_sam_sam]

An update on the situation with the new external switching power supply with this desoldering / soldering station working extremely well and no issues or problems with this new setup ran smoothly and for 4 hours today so far and probably 6 hours last weekend

[Agent24]

Great to hear!