More on voltage leakage

Since my post on voltage leakage from soldering iron tips leading to blown decoders I have done some more research and talking to my advisors. Here’s what I came up with. First, there are soldering stations like the Hakko FX888D-23BY available for under $100 that are grounded and ESD certified. rates this one as the best of the best whereas the WLC100 is rated as the best for the buck.

Since there is no guarantee that even these won’t develop a tip leak I have attached a PDF (Click Here) that outlines a method for testing soldering irons for voltage leakage. This was put out by the ESD Association. I only provide this document as a service and do not make any assertions as to it effectiveness or reliability. Please observe all safety measures when doing the tests.

Now for some more on how to avoid damage if your tip unknowingly goes bad and starts to leak electrons. First, it is unlikely that any damage will be done if the decoder is physically and electrically isolated from any earth ground during the soldering procedure. For this to happen do your soldering on a rubber or vinyl mat or some other non-conductive surface. If the decoder is installed in a locomotive and you are adding wires make sure the locomotive is on the non-conductive mat. Do not touch the decoder or model during the soldering process since you may become part of the conductive pathway and complete the circuit. Even holding a strip of solder in your fingers could complete the path–use plastic tweezers or a roll of solder in a plastic dispenser like the one shown here.

However as I described in my previous post on this subject your best bet is to remove the decoder, solder in the board or harness and speaker, then reinstall the decoder. Also, it is a not a bad idea to also disconnect your DCC system when soldering track feeders, rail joiners, or anything else to the rails or power bus.


  • Hi there, I bought the Hakko FX 888D from Amazon a while back,130 Dollars, found same unit at Fry’s electronic for 100 Dollars a few weeks later. Make sure you shop around before spending your cash! IMHO Amazon is practical but not always the cheapest. Having said that: The Hakko unit works really well! I am not an electronics guy but was able to modify a calculator by soldering wires on 1mm wide circuit traces without burning anything! Also comes with several replacement tips! Follow recommendation from the DCC Guy regarding solder and flux! Hope this helps a little, happy model railroading to all!

  • Though I’m now embarrassed to admit, I’ve blown several Tsunami decoders. This article give me hope going forward.

    Thanks, Larry

  • I likely won’t be soldering decoders in the near future, but great point about disconnecting the DCC system when soldering track feeders, rail joiners etc. Being fairly new to the hobby, that is good to know. Thank-you!

  • This was an important follow up. Thanks for this and all of the others.

  • Where can you purchase this soldering iron at?