An electronics primer

[Spartan]

Register to remove this ad. It's free!

Hi,

I found this site the other day and I'm giving serious consideration to building one of my own. I don't know much about the electronic components used in the control panel and I'd like to understand a bit about them before I begin this project. Can anyone recommend a primer I can read to learn about these things, be it a web site, book or even a textbook?

Thanks.

[cardmechanic]

http://www.radioshack.com/product/index.jsp?productId=3814337

Its 70$ and probably more than your looking for but its a great hands on way to learn.

[kal]

I'm not sure that an electronics kit is really going to help...

The control panel I designed is made up of mostly very simple components so you don't need to understand how discrete components like transistors, capacitors, resistors, etc, work.

The control panel is mostly only switches, relays (an electromagnetically controlled switch), lights, and then specialized devices like PIDs, a timer, a voltmeter, and a ampmeter. Inside these specialized devices are hundreds of tiny electronic components but you don't need to understand how they work any more than you need to know how a car engine works to drive a car. What you need to understand is how you CONTROL those devices and that's what my guide is for (or the product manuals, though they're cryptic sometimes).

What would certainly help too is a general understanding of electrical systems, 120V, 240V, AC, DC, etc. Terms like HOT, NEUTRAL, GND, etc.

I do try and explain the ones that are needed here: http://www.theelectricbrewery.com/control-panel-part-2?page=3

Wiring basics would also help. It's here: http://www.theelectricbrewery.com/control-panel-part-2?page=6

Kal

[kal]

I'm not sure that an electronics kit is really going to help...

The control panel I designed is made up of mostly very simple components so you don't need to understand how discrete components like transistors, capacitors, resistors, etc, work.

The control panel is mostly only switches, relays (an electromagnetically controlled switch), lights, and then specialized devices like PIDs, a timer, a voltmeter, and a ampmeter. Inside these specialized devices are hundreds of tiny electronic components but you don't need to understand how they work any more than you need to know how a car engine works to drive a car. What you need to understand is how you CONTROL those devices and that's what my guide is for (or the product manuals, though they're cryptic sometimes).

What would certainly help too is a general understanding of electrical systems, 120V, 240V, AC, DC, etc. Terms like HOT, NEUTRAL, GND, etc.

I do try and explain the ones that are needed here: http://www.theelectricbrewery.com/control-panel-part-2?page=3

Wiring basics would also help. It's here: http://www.theelectricbrewery.com/control-panel-part-2?page=6

Kal

[crush]

You don't really need to understand it if you follow the instructions as given, although a little understanding can help you realize why the circuit is designed in the away it is.

I only have a basic knowledge of electrics, and have not worked much with AC. So, when looking over Kal's design, it has been helpful for me to remember these things:

components can be wired together in series or in parallel.
components in series are "daisy-chained" - the "out" of one component connected to the "in" of the next.
components in parallel have their "in"s connected together and their "outs" connected together.

The arrangements have these consequences:
series:
the voltage difference across components in series is spread across each component in relation to how much current they draw.
the current passing through each component in series is the same. (Even if it's a low powered component, connecting it in series with a high-powered component will draw more current through the low-powered component.)

parallel:
the voltage across components in parallel is the same
the current across each component in parallel is different (each component takes what it needs)

With the control panel, most components need to get the full 120v/240v, it is rare to see components connected in series in Kal's design. Instead, they are connected in parallel. Each component then gets the full voltage (120 or 240 as required) and only as much current as it can handle.

Those few cases where components are connected in series, there is typically one component drawing any significant current, and the remainder of the series circuit are switches.

Search for "series parallel circuits" - the wikipedia entry http://en.wikipedia.org/wiki/Series_and_parallel_circuits seems quite useful.

Hope this helps get you started!

[Spartan]

[Sparky]

If you want to build it and get stumped along the way, you can ask questions here. Or, you can always get Uncle Spike to build you one!

[rosenjm]

The internet is probably your best resource. Like Kal said, pretty much everything in the control panel is a switch or a light.

Relays utilize a small control signal to actuate a set of contacts to operate high voltage or current components. This prevent us from having to use a switch (that your wrap your fingers around) that carries this high voltage or current. The DPDT relays Kal recommends use a 120 Vac, low current coil to magnetically operate a set of contacts through which the 240V 25 Amp heating elements are powered.

A SSR is simply a static switch, or a switch with no moving parts. When a gate signal is applied (from the PID) the switch "shuts" and allows current to flow from the power source, through the relay to the heating element.

Think if the PID and a mini-computer. It looks at the input temperature (BK, HLT, MLT) and then compares it to the setpoint. If it wants the temperature to go up, it shuts an internal relay which gates the SSR allowing it to "shut" and send power to the element. The element heats up and so on. The microprocessor in the PID does all sorts of wonderful things to ensure that the temperature is maintained in a specific band, but that is the basics of it.

Understanding is good! It will prevent you from hurting yourself and will assist in troubleshooting if required. By all means, if you don't understand what you are doing ask first!

[Spike Innovations]

[Spike Innovations]

[Spartan]

I ended up googling "PID." After figuring out that "Pelvic Inflammatory Disease" is not what I wanted, I looked at Wikipedia. A decent source for "PID for Dummies" with links to other sources for more info. A bit more studying and then on to "SSR."

[kal]

I also try and explain what these devices are in the text.

For example, for an explanation of what a PID is and how it works, see here: http://www.theelectricbrewery.com/control-panel-part-2?page=11

Kal

[kal]

I also try and explain what these devices are in the text.

For example, for an explanation of what a PID is and how it works, see here: http://www.theelectricbrewery.com/control-panel-part-2?page=11

Kal

[Spartan]

[kal]

I agree 100%. Kudos to you to want to learn. I recommend everyone try and understand how and why things work the way they do instead of just following my directions blindly.

Kal

[kal]

I agree 100%. Kudos to you to want to learn. I recommend everyone try and understand how and why things work the way they do instead of just following my directions blindly.

Kal