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In the beginning the problem I was having was relays actuating by a GPIO OUT signal that was not directed at them.

On the Raspberry Pi Forum user pcmanbob pointed out that my relays were designed to be actuated by 5v but the GPIO OUT signal that I was using to actuate them was only 3.3V He suggested adding a ULN2003 transistor which I soldered onto the Pi EZConnect hat shown.

This was when I went to all relays closing at boot and none of them responding to any GPIO signal. They Just stayed on.

After some breadboard testing with the ULN2003 I was able to get the relays to actuate according to the appropriate command but when I moved the setup back to the Pi EZConnect hat all relays still closed at boot.

The cause was the way the breadboard section of the Pi EZConnect solder pin holes were laid out.

[![Pi EZConnect layout][1]][1]Pi EZConnect layout

All pins going across the breadboard section of the Pi EZConnect are connected. Therefore the ULN2003 was being shorted/bypassed between its metal tabs across from each other.

The fix for me was to switch to a different hat with no connection between pins and make my own solder bridge between the wires and the nearest metal tab of the ULN2003. [1]: https://i.sstatic.net/TAJC5.jpg

In the beginning the problem I was having was relays actuating by a GPIO OUT signal that was not directed at them.

On the Raspberry Pi Forum user pcmanbob pointed out that my relays were designed to be actuated by 5v but the GPIO OUT signal that I was using to actuate them was only 3.3V He suggested adding a ULN2003 transistor which I soldered onto the Pi EZConnect hat shown.

This was when I went to all relays closing at boot and none of them responding to any GPIO signal. They Just stayed on.

After some breadboard testing with the ULN2003 I was able to get the relays to actuate according to the appropriate command but when I moved the setup back to the Pi EZConnect hat all relays still closed at boot.

The cause was the way the breadboard section of the Pi EZConnect solder pin holes were laid out.

[![Pi EZConnect layout][1]][1]

All pins going across the breadboard section of the Pi EZConnect are connected. Therefore the ULN2003 was being shorted/bypassed between its metal tabs across from each other.

The fix for me was to switch to a different hat with no connection between pins and make my own solder bridge between the wires and the nearest metal tab of the ULN2003. [1]: https://i.sstatic.net/TAJC5.jpg

In the beginning the problem I was having was relays actuating by a GPIO OUT signal that was not directed at them.

On the Raspberry Pi Forum user pcmanbob pointed out that my relays were designed to be actuated by 5v but the GPIO OUT signal that I was using to actuate them was only 3.3V He suggested adding a ULN2003 transistor which I soldered onto the Pi EZConnect hat shown.

This was when I went to all relays closing at boot and none of them responding to any GPIO signal. They Just stayed on.

After some breadboard testing with the ULN2003 I was able to get the relays to actuate according to the appropriate command but when I moved the setup back to the Pi EZConnect hat all relays still closed at boot.

The cause was the way the breadboard section of the Pi EZConnect solder pin holes were laid out.

Pi EZConnect layout

All pins going across the breadboard section of the Pi EZConnect are connected. Therefore the ULN2003 was being shorted/bypassed between its metal tabs across from each other.

The fix for me was to switch to a different hat with no connection between pins and make my own solder bridge between the wires and the nearest metal tab of the ULN2003.

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In the beginning the problem I was having was relays actuating by a GPIO OUT signal that was not directed at them.

On the Raspberry Pi Forum user pcmanbob pointed out that my relays were designed to be actuated by 5v but the GPIO OUT signal that I was using to actuate them was only 3.3V He suggested adding a ULN2003 transistor which I soldered onto the Pi EZConnect hat shown.

This was when I went to all relays closing at boot and none of them responding to any GPIO signal. They Just stayed on.

After some breadboard testing with the ULN2003 I was able to get the relays to actuate according to the appropriate command but when I moved the setup back to the Pi EZConnect hat all relays still closed at boot.

The cause was the way the breadboard section of the Pi EZConnect solder pin holes were laid out.

[![Pi EZConnect layout][1]][1]

All pins going across the breadboard section of the Pi EZConnect are connected. Therefore the ULN2003 was being shorted/bypassed between its metal tabs across from each other.

The fix for me was to switch to a different hat with no connection between pins and make my own solder bridge between the wires and the nearest metal tab of the ULN2003. [1]: https://i.sstatic.net/TAJC5.jpg