Getting started


Hi all
I’m running Jessie with an 8gb card on raspberry pi B+
I personally am a bit of a noob with the pi but love to build and tinker.
First I was having problems with the app on my iPhone 5s it would not find my pi for love nor money but I over come this problem with my personal URL code when I logged in using my pi and imputed the code provided into a terminal.
And bingo the app on my iPhone found my pi first time happy days.
But now I have now hit a new problem I would like to use my pi as a building management system and this app I think is the just what I need to remotely control my pi using my iPhone.
I’ve looked at the tutorial videos and as I believe my pi should load the dashboard after install ?
Or am I wrong?


Hey there,

Glad the app was able to find your Pi.

If the dashboard has not loaded (assuming we are still talking iphone here) after installling Cayenne onto your Pi, there are some possible reasons why.

Did you expand the file system on your Pi before running the Cayenne install?



Hi bestes thanks for the prompt reply.
No I haven’t I have had problems with the handshake between my phone and the pi.
I put this down to the noob factor. :thinking:


Hey no worries! Everyone starts out as a beginner. I send you a PM with a good tutorial.



Just for the record, the filesystem would usually be expanded if anyone, like a new Pi user, setup the Pi via NOOBS.


Ye that’s right it has done mate.
The wife has me decorating so no time to play with the pi.
Was having problems with a 16 channel relay board but unfortunately no time to play. :pensive:



I feel you pain my friend, my wife had reconstructive surgery done on her knee on Tuesday. I have been her go-to guy for just about everything since.

There is an example for wiring some relays here-

Also I have one of my 2-relay boards up and running so I can show you what I have done.



Hi all
Ok right we can all have a good laugh at the noob at this one.
I’m having problems with setting up a 16 channel relay board I’ve set Gpio pin 17 as an output and set my button up but it didn’t a lass it failed,
So putting my faith in bestes app I pulled out my trusty multi meter out the trigger is working as it should but the Gpio when high gives me 3.32v and when low 0.13v it’s not a lot but but it’s keeping the relay closed is thi right or wrong?


RPi GPIO’s are 3.3 volt out.
Do your relay’s look like the ones in this drawing?
Specificly, are the relays 5 volt, have SRD-05VDC-SL-C on the tops?
Do you have 5 volts going to the VCC on the relay board like in this diagram?

Next the GPIO needs to be hooked to the relay you want to control, in the below case it is GPIO13 to control relay 1 so it is hooked to IN1. And a ground needs to be hooked up. It should work as shown here, when the GPIO is pulled low the relay shoud click (opening the NC side of the relay) and the LED (IN1) indicator on the relay board should light.

These diagrams were stolen from this page-

Let me know if this doesn’t make sense,


The GPIO can't control my relay switch

Hi Ian hope the wife’s recovery going well,
This is the relay board I’m playing with.

I’ve got it up and running with a 10k resister and calling it @Ian I think helped for luck :smile:
The question was more about the output voltage when high or low.


Thank you so much for asking, she is dealing with lots of pain but we’re pretty sure she is going to live.

Good to hear! I’m guessing you have 12VDC going to the VCC then. This is a mistake I made not very long ago, got 12VDC relay’s when I didn’t have 12 volts available.

funny, thank you
I would call it @bestes, he is much younger so it should last much longer :grin:



I don’t think I’ve ever seen a relay hooked up like that. I am using mine like this: feel free to watch the whole video.


This board is 12v in and it also gives a 5v out to run the pi the eBay no is 262198219439 and the items info

So like I’ve said when the pi’s Gpio is set as an output and when it goes low should there be any voltage out ?


Gavin does make a compelling argument in the video for not using the jumper in these circuits, starting at about 7:45

Thanks Adam.

Hi @4ndy,
Sorry I have to run, back to work today.



I’m not really sure what you’re asking. When you set the GPIO low by default there shouldn’t be any voltage. It basically turns the pin off.


That’s what I thought there seems to be a small output of 0.13v and its activating the relay.
Has any one put there meter on a pi Gpio pin when it is set as an output and low ?


No, I have not. I just searched google to see if that is normal and couldn’t find anything relating to output voltage on a LOW pin. I don’t have a multimeter with me but I can check tonight to see what my Pi does.


Thanks Adam that would be great I did research it myself before I asked but I couldn’t find anything.
But like you I don’t think there should be anything coming out.
But this is the thing that keeps me up at night.
(if high is on and low is off) it contradicts itself because low is not off its just smaller amount then high these are my nightmares lol


On my Pi low is reading -2.9v


try the good people on the forum for these sorts of answers.