What's Needed for a successful Home Brewery
Most fully electric home breweries are based on a 5500 Watt water heating element for the brew kettle, a 5500 Watt water heater element for the hot liqour tank and a 1650 Watt to 5500 Watt water heating element for the mash tun or RIMS tube. Add all of these together and you could easily be at 16500 Watts just for heat and to run all three of these at once would require 68.5 Amps at 240 VAC.
But as shown in the picture above, you really only need one of these elements on at a time.
One 5500 Watt heating element only draws 22.9 Amps, making an existing 30 Amp dryer outlet or a new install dryer type outlet the ideal power source for an Electric Home brewery. The 7.1 Amps left over leaves plenty of room for other accessories like electric pumps and electric valves.
Tom - www.kegkits.com
Step 1: Voltages Delivered to Your House
The main utility power feed to your line transformer is usually around 7200 Volts AC. Your line transformer drops this high voltage down to two 120V voltages that are connected in series. The connection between the two is called a center tap and the center tap is connected to earth ground with a metal stake that's hammered into the ground.
Voltage is a measurement from one location to another that have a common electrical connection. For example a common flashlight battery is 1.5 volts - that's the measurement from one end of the battery to the other end of the battery. But if you were to measure from the top of one flashlight battery to the top of another flashlight battery you would not read any voltage because they are not connected together. Line the batteries up end to end & facing the same way and measure the voltage from one end to the other. You will measure 3 Volts because 1.5 Volts + 1.5 Volts = 3 Volts. This is called a series connection - the two batteries are connected in series.
The power connection to your house is no different. The voltage from the center - earth ground to either power lead coming off your transformer is 120 VAC but just like the battery example I showed earler, the voltage across the two in series, the two outside wires is 240 VAC.
Step 2: Power Options Available at Your House
Current flows between positive and negative voltages and current X voltage = Watts. Watts or Watt/Hrs (Watts over time) does all the work in anything electric. The interesting thing about Watts and Watt/Hrs is that both are universal. Once you convert to Watts and Watt/Hrs you can ignore current and voltage.
120 Volts X 10 Amps = 1200 Watts
240 Volts X 5 Amps = 1200 Watts
The watts or wattage is the same even though the voltage changed!
This is because when I doubled the voltage I halved the current.
1200 Watts X 1 Hr = 1200 Watt/Hr
600 Watts X 2 Hr = 1200 Watt/Hr
2400 Watts X 30 Min (1/2 Hr) = 1200 Watt/Hr
The Watt/Hr is the same even though the Watts changes!
This is because when I changed the Watts I changed the time in the other direction.
So, knowing all this we can see what's available in most homes to power your home brewery.
Most home non-kitchen outlets are on 120 Volt, 15 Amp circuits. Knowing that Volts X Amps = Watts it's easy to see that 120 Volts X 15 Amps = a maximum of 1800 Watts and this is not near enough power to run a home brewery.
Most home kitchen outlets are on 120 Volt, 20 Amp circuits. Knowing that Volts X Amps = Watts it's easy to see that 120 Volts X 20 Amps = a maximum of 2400 Watts. While 2400 Watts is not enough power to run a full home brewery this is enough power to bring 5 gallons to boil. Also, modern kitchens are wired with two 20 Amp circuits and you can use both together to boil 10 gallon batches and even setup a mash tun. But brewing this way means invading the kitchen every time you brew beer.
This is where your dryer outlet or a new 30 Amp "dryer like" outlet comes in. A dryer outlet is wired across 240 VAC, plus it's a 30 Amp circuit. This makes your dryer outlet a 240V X 30 Amp, or a 7200 Watt power source! And with 7200 available Watts you can run a 5500 Watt Water Heater element and have plenty of Watts left over to run circulation pumps and electric valves.
Step 3: GFI Protection
GFI is a great system - GFI outlets and breakers work by watching the current flowing through the wires feeding your outlets. As long as the current is in balance, as long as what goes in is coming back out the GFI does not trip. But as soon as the current is not in balance the GFI trips, cutting off power. A GFI protects you because if you are getting shocked the current passing through you is not being returned through the breaker or outlet. Instead the current is passing through you to ground.
But get your body in between power and GFI ground the GFI breaker will not trip. This is because the GFI does not know the difference between current passing through a heating element, through a pump motor or through you. It's all the same because all of the current being delivered through you would still be returning through the GFI. In other words a GFI outlet or breaker will not protect us from "stupid"!!!!
Regardless it's a good idea to use GFI for your home brewery. If you will be using an existing non-GFI dryer outlet there are several extension cord style GFI breakers avalable that you should consider using.
Step 4: The 120V Outlets in Your House
Your 120V house outlets, including the ones in your kitchen, are connected to Neutral and one of the 120V lines coming into your house.
Then the outlets are connected together until the maximim number are installed by code, in most houses up to 7 outlets are connected together to one breaker in your main panel.
The third bare wire connected to your outlets is a safety ground.
Step 5: Existing 3 Wire Dryer Outlets
Three wire dryer outlets are wired across both 120 VAC circuits in series, delivering a total of 240 VAC. The ground and neutral are provided by one common ground wire. The system works because back at your main electrical panel ground and neutral are connected together making them the same electrical circuit.
With a 3 wire system anything needing 240 Volts like your main heating element is wired across the two hot wires. And anything needing 120 Volts is wired across one of the hot wires, it does not matter which one, and ground. The ground carries the difference current back to the main panel while still serving as a safety ground.
Step 6: Newer 4 Wire Dryer Outlets and Any New Installs
The only difference between 3 wire and 4 wire dryer outlets is the safety ground and neutral are connected to the outlet with separate wires. The safety ground and neutral are still tied together at your main power panel making them the same electrical connection. Keeping safety ground at the outlet separate garantees that no matter what, the safety ground is at ground voltage. And even though it's highly unlikely with proper wiring, combining safety ground and neutral into one wire like the older 3 wire system could set up a situation where the safety ground would not protect you from electrical shock.
With a 4 wire system anything needing 240 Volts like your main heating element is wired across the two hot wires. And anything needing 120 Volts is wired across one of the hot wires, it does not matter which one, and neutral. The neutral wire carries the difference current back to the main panel and the safety ground stays separate.
Any new power installs like a new outlet for your home brewery should use 4 wires.
More info can be found at www.kegkits.com. - Tom