This is a 4 pin replacement female spindle connector with a 20mm threaded connection for mechanically securing this connector to the spindle.
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The pin spacing is approximately 0.22 inches or 5.62 mm. The 4th pin is reserved for ground. Pins 1, 2 and 3 are for the three phases of the spindle U,V and W. You can also use this connector for other applications that require a strong mechanical threaded connection.
To establish a soldered connection between the cable and connector pins, follow these steps:
Each pin features a cup-shaped lead on its rear end, designed to hold a pool of solder.Start by applying rosin core solder inside this cup.Also, tin the end of the wire that you'll insert into the cup by applying rosin core solder to it.Heat the cup already containing some solder, and while it's melted, insert the tinned wire into it.The use of rosin core solder on both the cup and wire end ensures that the flux aids in forming a strong solder bond between the two components.