SeeMeCNC Rostock MAX v2 Assembly Manual page 77

Next, solder down the leads to the solder pads. Make sure you don't create a solder bridge
between the two pads. Use only enough solder to do the job. When you're done, clip off the excess
leads.
Note that we're using the pair of pads closest to the thermistor. The farther pair is where we'll
install the thermistor signal wires.
Fig5C-10: Soldered down...
We're going to install the power LEDs next – the
LEDs has polarity to themn, so we need to make sure
that each LED is installed correctly, otherwise they
won't light up.
The flat side of the LED is the "cathode" or negative (-) side. You want to insert the diode in
the holes with the cathode lined up with the square pad as shown below.
Bend the leads over so they are laying flat against the two solder pads as shown below and then
solder them into place.
Rostock MAX v2 Assembly Guide
Fig. 5C-12: Power LED orientation.
Fig. 5C-11: ...and clipped.
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