Week 7 (In Lab) - Soldering Relay System

Figure 1. Relay with soldered wires. Black tubing: hot wire on pump side. Yellow tubing: 5V input from Arduino. Green tubing: ground on Arduino. Uninsulated connection: hot wire on plug side.

In lab this week, the team was able to solder all wires directly to the relay, eliminating the need for alligator clips. This was advantageous to the project for two reasons: 1) soldering provides more secure connections all around (the team was having some trouble with electrical tape coming off and some connections coming undone), and 2) soldering decreases the overall system length by about two feet of cords, making it much easier to fit inside a single container. 

Three of the connections were partially insulated with heat shrink tubing. Additional insulation with electrical tape (as well as complete insulation for the fourth connection) is needed. The lack of heat shrink tubing on the fourth connection was not intentional and should not be purposely replicated if this project were to be repeated. Figure 1 shows the relay with all soldered wires.