EK006 8x Serial Relay Board
Part.no: 41015615
EK006 is a relay board with 8 SPDT relays that can be controlled serially via a shift register.
The board provides a simple way to connect multiple relays to a microcontroller and requires only three signal connections, in addition to 5V and ground.
The relays can also be controlled directly in parallel by leaving JMP1 unbridged.
Multiple relay boards can be connected in a chain without using additional connections on the microcontroller.
Each relay has one normally open (NO) and one normally closed (NC) contact. When the relay is inactive, COM is connected to NC. When the relay is active, COM is instead connected to NO.
The relay board is connected to a microcontroller using clock, data, and latch signals. For more information on how the signaling works, see the datasheet for the shift register 74HC595 (74hc595.pdf).
The serial connector also includes 5V and ground, which can be used either to power the microcontroller or to power the relay board from the microcontroller. Do not connect voltage to both VIN and 5V on the serial connector at the same time, as this will damage the circuit.
- Supply voltage: 5VDC
- Current draw: 720mA (all relays active)
- Relay contacts: 250VAC, 10A / 30VDC, 10A
- Dimensions: 50.8 x 171.45mm
- Mounting holes: c-c 44.45 x 165.1mm, ø3.175mm
Warning
If the relay board is used for controlling 230VAC, be extremely cautios as the underside of the board exposes the relay contacts!
The board should always be mounted on an insulating surface to prevent shorts!
Component list
| RefDes | Value | Qty. | Part.no. | Marking |
|---|---|---|---|---|
| IN, OUT, SER_EN, PL | Pin header 1x40-pol | 1 | 41001167 | |
| JMP1 | Jumper 2.54mm 2-pol | 1 | 41000598 | |
| C1 | El.lyt 100uF | 2 | 40520007 | 100uF |
| C2 | Ceramic 100nF | 1 | 41003038 | 104 |
| D0 - D8 | LED 5mm red | 9 | 40307020 | |
| D9 | Diode 1N4004 | 1 | 40310004 | |
| K1 - K8 | Relay SRD 5V | 8 | 40230001 | |
| R0 - R8 | Resistor 330ohm | 9 | 40811233 | |
| R9 | Resistor 10kohm | 1 | 40811410 | |
| U1 | Shift register 74HC595 | 1 | 40370595 | SN74HC595N |
| U1 | DIL socket 16-pin | 1 | 40410016 | |
| U2 | Driver ULN2803A | 1 | 41021748 | ULN2803A |
| U2 | DIL socket 18-pin | 1 | 40410018 | |
| VIN | Screw terminal 5mm 2-pol | 1 | 40210002 | |
| CON1 - CON8 | Screw terminal 5mm 3-pol | 8 | 40210003 |
Assembly guide
Before starting assembly, check that the PCB is free from damage and scratches. Verify that all components to be assembled are present, compare with the component list.
It is usually easiest to start assembling the lowest profile components and work upwards in size. IC sockets, resistors, ceramic capacitors and diodes are mounted first. Electrolytic capacitors, connectors and potentiometers are mounted last.
For some components, correct orientation is important. Pay attention to the markings on the PCB.
Interactive assembly guide ↗
Example code and datasheet
Schematic
Drawing
