Weller WTCPT soldering iron switch mod

This simple modification replaces the standard rocker switch with an illuminated type rocker switch that is a drop-in replacement.

One annoying thing about the Weller WTCPT soldering iron is, there is no in-your-face indication it’s on, and it’s easy to inadvertently leave it on.

Whilst there is a red mark on the top of the rocker switch, you need to be virtually on top of it to see it.
If you’re at arms length away – forget it!

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To do this mod you will need:

• Illuminated Red SPST Rocker Switch, On-Off, 10 A@ 125 VAC 19.2mm x 13mm
  RS part number 419-782   $3.38 + GST.   (Free delivery with on-line orders)

• 12 cm of mains rated wire

• 4.8 mm female spade lug (tight ass option: directly solder to switch terminal)

• “BP” mains connector (we’re dealing with mains – so do it properly)

• heat shrink (optional)

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Unless you have a second soldering iron (think about it!), solder 12 cm of wire to the spade lug first.
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As a matter of routine, I will heat shrink over all the spade connectors.

 

Now, you can disconnect and disassemble the iron by removing the four screws hiding under the rubber feet.

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The standard rocker switch is a typical snap fit, and pops out with pressing down on the mounting ears.

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To power the neon indicator we need to take off the neutral using the pre-prepared 12 cm lead.

Cut off the existing termination (this gets rid if the spiral), and splice the three wires together, covering with the “BP” connector:

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Diagram of switch:

rocker-switch

• pin 1 – mains active (brown wire)

• pin 2 – to transformer (black wire)

• pin 3 – mains neutral

 

Now it’s plug ‘n play.

So that the iron is “on” in the down position (as per standard), orientate the switch so that pin 1 (mains active) faces the top.

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Re-assemble iron and behold!

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Very easy to see if it’s on or off.