Simple Relay Shield Assembly v2
This page walks through the process of assembling the Simple Relay Shield v 2.0 Kit.
 Bill of Materials, or, "What's in the kit?"
|Line||Qty||Reference||Value||Vendor||Vendor Part Number|
|1||1||PCB||Circuit board, Simple Relay Shield||Evil Mad Scientist||9600033|
|2||2||R1, R2||1000 ohm 1/4 W Resistor||Digi-Key||Digi-Key 1.0KQBK-ND|
|3||2||D1,D2||1N5817 Diode, Schottky||Digi-Key||Digi-Key 1N5817-TPCT-ND|
|4||1||D3||Red T1 LED||Evil Mad Scientist||9330026|
|5||1||C2||100 uF 10 V Capacitor, electrolytic||Digi-Key||Digi-Key P963-ND|
|6||1||C1||0.1 uF 25 V Capacitor, ceramic||Digi-Key||BC1148TR-ND|
|7||1||Q1||2N4401 Transistor, NPN||Digi-Key||2N4401D26ZCT-ND|
|8||1||J1-J4||6/8-pin female stacking header set||Evil Mad Scientist||633|
|9||1||J5||3-pos, 5.08 mm Term block||Digi-Key||ED2610-ND|
|10||1||Relay||G5LA-14 DC5 SPDT, 5A||Digi-Key||Z2560-ND|
 Assembly procedure
We'll go line by line through the kit components. This guide assumes that you have had some soldering experience. If not, or it's been a while, you may also want to look at pages 2 and 5-7 of the Bulbdial clock assembly instructions, which go over basic tools and technique. And, if you really are a beginner, there are plenty of good tutorials on line, like this one.
 0. The simple relay shield kit
Here are all the components that make up the kit:
We'll be adding components to the various locations labeled on the board.
 1. Install the two 1k ohm resistors
The 1k ohm resistors will be installed in location R1 and R2. Shown here:
First, bend the resistor leads as shown:
Insert the first resistor in location R1 (Resistors are not directional and can be installed either way):
Bend the leads outward to keep the resistor in place while soldering:
Solder both leads:
Make sure you have a good solder joint from the PCB pad to the resistor lead. The solder joint should be shiny without too much excess solder.
Clip the excess leads short on the back side.
Then, install the second 1k ohm resistor at location R2, in the same manner. Again, solder both pins and clip the excess leads short.
When you've finished adding these two resistors, your board should look like this:
 2. Install the two diodes
Bend the leads as shown:
Install the diodes in positions D1 and D2. Diodes have polarity - be sure to match the stripes on the diode with the stripe on the PCB.
Just as we did with the resistors, bend the leads outward so they stay in place during soldering. Solder. Check for a good solder connection and clip the excess leads.
 3. The LED
The LED will be installed in location D3, which is next to the resistors.
Orientation is important: the long lead goes into the square hole.
Insert the LED but before soldering, you can bend the leads out at 45 degrees to hold an LED in place while you solder. Solder both leads and clip the leads short.
 4. The capacitors
There are two different capacitors in the kit. This is C1, a ceramic capacitor. It has a little yellow body and two long leads:
And this is C2, an electrolytic capacitor. It has a short, cylindrical body:
Insert the little ceramic capacitor into C1, with either orientation.
C2, the electrolytic capacitor, has a polarity. It must be installed with the "minus" side -- marked by the large white stripe on the side -- to the "-" side on PCB, as shown above.
Just as before, bend the leads outward, solder, and clip the leads of both capacitors.
 5. The transistor
Install the transistor in location Q1:
Orientation is very important: Match the flat side of the transistor to the flat side drawn on the PCB. The transistor will not sit flush but you can still bend the two outer legs to keep in place for soldering. Solder all three pins on the bottom side and clip the leads.
 6. The 'Stackable' Headers
The Simple Relay Shield is intended to be used as a 'shield' with an Arduino or Arduino-compatible board, and so it comes with the appropriate 'stacking' headers.
The headers will be installed in the outermost holes. The two 6-pin headers on one side, 8-pins on the other, as shown here:
To add these, we recommend inserting all four headers and then resting the board-- upside down --on the four headers, so that they sit flush to the board.
Solder one end pin of each first.
Flip the board back over and check that the pins are perpendicular to the board. Make sure the headers aren't 'twisted' in their sockets - make sure the edges of the socket are parallel with the silkscreen outline on the board.
If any header/socket isn't aligned correctly, heat up the solder on the single soldered pin and adjust the header/socket as needed.
Once everything is aligned, flip the board back over and solder the rest of the pins. Try to use a minimal amount of solder, so that solder does not wick down onto the pins, as that could potentially cause difficulty inserting the shield into an otherwise receptive Arduino board. Do not clip these leads.
The board so far:
 11. The terminal block
The terminal block goes in location J5 -- with the holes facing outward, as shown:
Similar to the headers, solder 'tack' one of the pins to keep the component in place, turn the board over and check that the terminal block is straight and flush with the PCB before soldering all three pins.
 12. The relay
Finally, it's time to add the relay -- it can only go in one way -- and solder it in place:
 13. Control signal
Last step! Decide how you would like to control the Simple Relay Shield, and wire a jumper to the control input.
The default configuration is to control the relay through pin Digital 4 (D4). If you would like to control it that way, then install the zero-ohm jumper wire (which looks like a resistor with one black stripe) in the location marked JP, by the transistor:
If, instead, you would like to control it from a different signal line, connect the zero-ohm jumper wire (or a different wire of your choosing) from the side of location JP marked by the black diamond (♦) to the signal source. For example, you could wire up the Simple Relay Shield to line Digital 7 (D7) by soldering the jumper as follows:
And, you're done! Next, head back to the main Simple Relay Shield kit documentation page.