tag:blogger.com,1999:blog-6238454757421809452.post2614492848562858930..comments2024-01-29T06:22:58.174-05:00Comments on The Raspberry Pi <br>Hobbyist: GPIO Output Relay Interface Ted B Halehttp://www.blogger.com/profile/16887056993667506084noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-6238454757421809452.post-28327343758011530762014-09-25T14:03:20.080-04:002014-09-25T14:03:20.080-04:00What would be the considerations to relay 127VAC?
...What would be the considerations to relay 127VAC?<br />I want to turn on/off the amplifier I use with the RPI.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6238454757421809452.post-86618815642490183122014-04-04T23:08:02.422-04:002014-04-04T23:08:02.422-04:00In my application, the base is connected to a GPIO...In my application, the base is connected to a GPIO pin with the pull down resistor enabled. So, it is already biased to ground. I should have pointed this out. A more correct drawing would show a 10K ohm resistor connecting the base to ground.<br /><br />Many times I have disconnected the GPIO ribbon cable, which DOES leave the base open. It still doesn't burn up. At 5V, the 2N2222 is a pretty robust transistor.Ted B Halehttps://www.blogger.com/profile/16887056993667506084noreply@blogger.comtag:blogger.com,1999:blog-6238454757421809452.post-38566598866842518522014-04-04T20:30:56.295-04:002014-04-04T20:30:56.295-04:00Unless you Bias the Base to ground, it WILL burn u...Unless you Bias the Base to ground, it WILL burn up!<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6238454757421809452.post-40490544687576661022013-04-01T21:38:21.753-04:002013-04-01T21:38:21.753-04:00the max232 is perfect for type circuit!!!!the max232 is perfect for type circuit!!!!Anonymoushttps://www.blogger.com/profile/17120759993899404236noreply@blogger.comtag:blogger.com,1999:blog-6238454757421809452.post-74411822569989823842013-02-14T23:54:05.635-05:002013-02-14T23:54:05.635-05:00Probably. A quick Google search didn't show a...Probably. A quick Google search didn't show any, but I'm sure there are some out there or soon will be.<br /><br />The circuit I show says 5V, but that is just because that is what I used. The 5V power can be taken from the GPIO pin. Just be careful not to draw too much current or the voltage will drop and the Pi will hang or reboot.<br /><br />You can use the same circuit to control a 24V relay, but you may need to choose another transistor for it to work well. And, obviously, you must supply the 12V to switch the relay. The Pi just needs to switch the transistor. Ted B Halehttps://www.blogger.com/profile/16887056993667506084noreply@blogger.comtag:blogger.com,1999:blog-6238454757421809452.post-47350975816557198722013-02-14T21:03:17.292-05:002013-02-14T21:03:17.292-05:00Are their easy extension board to drive a 24V rela...Are their easy extension board to drive a 24V relay via the GPIO pins with the Raspberry Pi boards?SGhttps://www.blogger.com/profile/02113053911225387942noreply@blogger.com