Quelltext der Seite WSAL11638 – RPi Relay Board/en

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'''Documentation notice:''' This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

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[[File:JWTech-Wiki-preview-b2e0587d68b6ccf5d122643634b43786f4b9273c3171c3df26bbee0b4b944753.jpg|thumb|right|320px|alt=Product view RPi Relay Board|RPi Relay Board]]
'''Catalog location in the JW Tech Shop:'''
* WSAL11638 – RPi Relay Board: AI → Expansions → Motors / Relays / SCR; Misc Modules → Others → Power / Relays / SCR; Raspberry Pi → HATs → Motors / Relays / SCR
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== Summary ==
The RPi Relay Board is a Raspberry Pi expansion board with three relay channels driven via GPIO pins. It allows switching external loads through NC/NO contacts and provides demos in shell, C (bcm2835/wiringPi), Python, and web-based control.

== Related products at JW Tech ==
* [https://shop.jw-tech.eu/p/WSAL11638 WSAL11638 – RPi Relay Board]

== Technical overview ==
* Three relay channels (CH1–CH3) map to RPi pins P25 (BCM 26), P28 (BCM 20), and P29 (BCM 21).
* The Relay_JMP jumper must be installed for the Raspberry Pi to control the relays.
* Relays are low-level triggered: a Low output lights the corresponding LED, closes the NO contact, and opens the NC contact.
* Each channel has a screw terminal block with three pins for connecting external circuits.
* When cabled instead of stacked on the pin header, connect 5V, 3.3V, and GND for power.
* Multiple boards cannot be stacked due to relay height; they can be daisy-chained with Dupont cables.
* The demo package includes shell, C (bcm2835/wiringPi), Python, and web-control scripts accessible on port 8080.
* If the control signal appears inverted or no response occurs at high level, it is because the relay activates on a low signal.

'''Commands and examples – verify before use:''' 
<syntaxhighlight lang="text">
sudo ./Relay.sh CH1 ON
sudo ./Relay.sh CH2 ON
sudo ./Relay.sh CH3 OFF
make
sudo ./Relay_Module
sudo python Relay_Module.py
python3 main.py
</syntaxhighlight>

== Notes and version constraints ==
* Library versions (e.g., wiringPi 2.52 vs. 2.70) depend on the OS version; verify before installing.
* Web control requires Google Chrome; other browsers may be incompatible.
* After running the Python demo on VisionFive2, pins may become unresponsive — restart or run clear.sh.
* Specific voltage values, certifications, or warranty details are not provided in the source; do not invent them.

== Source and revision record ==
* [https://www.waveshare.com/wiki/RPi_Relay_Board RPi Relay Board - Waveshare Wiki]
* Source revision: 69155
* Captured: 2026-08-29T08:10:01+00:00
* SHA-256: <code>143f5493878f5bf4460435c0fcba1c1ada7210c93c1f04fb4fabf449de784e31</code>