# Rasberry Pi GPIO pins not switching
**URL:** https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658
**Category:** General
**Created:** [22 April 2022 18:17 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658 "2022-04-22T18:17:13Z")
**Posts on this page:** 6
**Page:** 2
### Author:  [@iiot2k](https://discourse.nodered.org/u/iiot2k)
#### Post date: [24 April 2022 10:48 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/21 "2022-04-24T10:48:14Z")
This relays don't work with RPI, because the gpio output is too weak to drive the inputs of relays. For 1-3 pins works, but if you connect more, the output driver of RPI is out of valid range.
The solution is to use a very cheap driver IC. If you want, I can share the wiring diagram here.
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [24 April 2022 16:37 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/22 "2022-04-24T16:37:30Z")
I think the issue is that the sainsmart 12volt relay requires its own 12 power rail.
No dirver chips are needed as this is included on the relay board.
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### Author:  [@iiot2k](https://discourse.nodered.org/u/iiot2k)
#### Post date: [24 April 2022 19:57 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/23 "2022-04-24T19:57:12Z")
If you look at sainsmart website:
##### SPECIFICATION:
- 12V 16-Channel Relay interface board, and each one needs 15-20mA Driver Current
How is this possible with max. 16mA on each pin and max. 50mA rail current on 3.3V?
16x15mA=240mA
🤢 -\> Raspberry Pi
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### Author:  [@ghayne](https://discourse.nodered.org/u/ghayne)
#### Post date: [24 April 2022 21:36 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/24 "2022-04-24T21:36:40Z")
> [@iiot2k](#):
>
> If you want, I can share the wiring diagram here.
I'm sure it would help!
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### Author:  [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)
#### Post date: [24 April 2022 22:54 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/25 "2022-04-24T22:54:01Z")
12Volt power doesn't come from Rpi - only logic level to trigger the relays via transitors onboard.
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [23 June 2022 22:54 UTC](https://discourse.nodered.org/t/rasberry-pi-gpio-pins-not-switching/61658/26 "2022-06-23T22:54:10Z")
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