My ultimate aim is to build an automatic temperature controller for my pellet grill. When I bought it, my grill came with a manual 3 way controller – Smoke, Medium and High. All that does is control the feed of fuel by time, not temperature. It works, but it isn’t as flexible or as accurate as I’d like.
In the States, these grills come with an option of digital temperature controls, which – due to the different voltage – is not available over here.
Then I found a supplier who were re-engineering the digital controls for 220-240V, so I ordered one. Unfortunately, when it arrived, I found that the controls they were re-engineering were old (for the US) stock – a model generally accepted to have poor logic. Furthermore, it didn’t actually fit my grill (not without a hacksaw), so I sent it back for a refund, and found myself back at square one.
On one of the forums I read, there are some guys playing with PID controllers, with some success. But then I came across the Arduino, and the wealth of add-ons available. There are already some people using it for BBQ control, although not the same kind of grilll as mine; they are controlling airflow (and thus temperature) with a simple low-voltage fan, whereas I need to control the pellet feed mechanism, which means controlling a 240V relay. Should be possible, though.
For the moment, I have just purchased the Inventor’s kit, to have a play – I can simulate my grill with a couple of LEDs, and see if I can get the right logic working. Then I can start buying the additional components I need – the relays and a WiFi add-on.
I will probably spend as much as I was going to on the digital controller, and possibly more than the guys using PIDs. But what I hope to end up with is something that is remotely monitored and controlled over WiFi, so it can be cooking downstairs, while I am working upstairs. Because the interface is going to be web-based, I should be able to access the controls from my desktop or even from my Android phone!
But that is a long way off, I think. I’m just going to play for a while.