Electrical Primer for Brewers

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Hey CodeRage, thanks for putting all this great info on here. One question I have is I recall having heard about sizing wire that for continuos loads you should only plan to draw 80% (don't quote that, I think thats what I heard) of the current that the wire can handle for intermitent loads (again can't really remember what how long you have to leave something on for to be classed continuos load). So if a wire is good for 20 amps intermitent you should only run 16 amps continous.
your advice?
 
The continuous load rule applies when the load is above 80% in excess of 4 (maybe it was 7?) hours at a time. It's usually applied to lighting circuits that are on for an entire business day. For our breweries it doesn't apply. It isn't a bad practice, but we don't need to strictly adhere to it.

EDIT - It's 3 hours, thanks BrewBeamer!
 
Thanks (and thanks again since I need to type more than 10 characters)
 
For a 240V heating element circuit, do I need to put a fuse on both hot legs. I have 3 elements and six SSR's (one for each leg). I am guessing I need to put a 25A fuse on each hot leg since I am using 4500W elements. I have another question. I know I have to protect the "hot" wires with fuses when I step down to a smaller gauge, but do I have to protect the neutral wire when I step it down in size? I enters the brew rig's panel as 6 ga wire with 50A supplied to it, I only need to use it for two 1/3 HP pumps and a 12V power supply.
 
Excuse my ignorance... electricity is something I know NOTHING about.

I went out and purchased a 3 prong, 30A cable and outlets today to put into my future control box. On the package for the outlets, it says "Not for grounded use except with Dryers or Stoves per the NEC code". It also says the 3 wires should be hot, hot, neutral.

Question, can I just use the 3rd wire safely as ground since I have complete control over what wire is what in my cable? I am using this to connect my control panel to my BK element.

Thanks!
 
Excellent work, rage! Thanks for writing it up. I will be using it for years to come.

This really needs to be a sticky for one important reason: safety. Question, why isn't it a sticky?
 
Thanks, I was at menard's yesterday, and I found .25A Fast Acting fuses for my control box, and they had Time delay fuses. I assumed they were the same as Slow Blow, just wanted to make sure.
 
To all the brewers who provided great information, thank you.
I start writing answers to some of these questions and then have to re-edit my responses because I need to get more detailed. I want to try (as I’m sure others do) and cover as many bases as possible so no one gets hurt or killed. Respect The Volts! (I know it’s current, but it doesn’t sound as good…)
SAFETY FIRST. As has been mentioned in this thread, electricity will kill you fast. Yes, it’s sometimes a PITA to go to the panel and shut off a breaker, but you’ll still be alive. (From my point of view, it’s probably the most exercise I’ll get all day.)
An inexpensive multimeter is a worthwhile investment. Flexible leads will also make your life easier. Some cheap azz meters/cord combos have cords that are too stiff and can wind up pulling the meter off a table or shelf, causing you to become distracted. The meter should also have slot at the top of the meter to put one of the probes in. This way you can put the meter/probe on the neutral bus and use the other lead to measure power at the breaker or hot terminal.
Don’t assume that the person who did the wiring before you did it correctly. If you have to assume anything, assume that the previous homeowner or landlord was the stupidest person on earth. Check first and be sure! Some houses have had more than one owner, which means more opportunities to have something done wrong. Homeowner #1, “Wiring For Dummies” in one hand, screwdriver in the other, “I don’t have the time to run to get the right parts, I’ll just take a short cut.”
The National Electric Code (NEC) is NOT law by itself. Municipalities, governments, etc. usually use a current version of the NEC (Most current is the 2011.) For example, here on Long Island, some towns use the ’05 code, others use the ’08 code. They take the NEC and make it law and usually amend it to make it more stringent. If you need to consult the NEC, I would suggest using the NEC code handbook. It’s the same code, but has explanations of some of the Fine Print Notes and diagrams, etc.
BrewBeemer, I like when people quote the NEC here, it gives me the chance to look up the citation and learn more.
Also, no matter what we say here, the final word lies with the Authority Having Jurisdiction (AHJ). Some places use an independent inspection company, others use an inspector from the Building Dept., or Power Company (POCO). Be nice to the inspector. They can make your life hell. If you have a question, ask it. Most inspectors will be happy to answer your questions or provide an explanation.
SUB PANELS. Like Pickles said, keep ground and neutral buses isolated from each other. Ground bus bonded to the panel itself, not the neutral. The neutral doesn’t get bonded to anything in the panel. Grounds to the ground bus and neutrals to the neutral bus, no mixing and matching.
Hermit. “Check from the third wire, whether it is neutral or ground, and see if you get voltage. Sinks, wall plugs if they have the third wire, copper plumbing, etc. If you get voltage between the two then you have problems. Chances are you won't see anything. Check from a hot to the test ground to make sure it is in fact grounded. But yes, in a properly wired environment neutral and ground are virtually the same. The earth ground is used to have a common reference. If you are pretty far from the transformer or have some other unusual circumstance, then they may not be the same.” With the advent of more and more plastic in our lives, using plumbing as a ground reference may not always work. At one time panels were grounded to the water main. Then we had to add a jumper to bridge the meter to the “street” side of the meter (rubber gaskets/Teflon tape may isolate the meter from the rest of the plumbing). Now some areas are using plastic pipe to deliver water to your house. Goodbye nice grounding point.
 
Hello all you electric brewers!

I just joined this site, and would love to participate in the electric brewing forum. We are relatively new to brewing, less then 12 batches, all extract. I believe the only way we'll ever try all grain brewing is to go electric.

You see I'm currently a systems integrator working in the mineing industry. I'm also a journyman electrician, and would like to learn how to brew using all grain methods, so I can create and automate a system. My first choise would be using a simple PLC, like a Modicom Momentum, or AB Micrologic to regulate pH, and temp durning the mash. I think this method would be better then a single loop PID controller as one could run multiple PID's and multiple I\O's.


BTW, Shuie, are you on Pelican Parts BBS?
 
Good to have yah 941MxVet and welcome to the board!

I'm a systems integrator for the fresh and waste water industry myself. Sure you don't want to try a coal fired brewery?

Guess that would be like me using methane from a solid waste digester. pass... :)
 
Thanks for the welcome CodeRage!

I work in the gold mineing industry though, not coal. I automate the extraction of gold from it's host rock through the Merrill Crowe process. This entails grinding, leaching with cyanide, plenty of de-arration, lead introduction, DE, as well as filter presses. I'm sure if you work in waste water you're familar with Perrin filter presses, we use the same units.:mug:

I think I'll be looking to improve my homebrewing so we can justify building an all grain home brewery!

Again thanks for the welcome, I'll be spending quite some time reading through these threads.

Rob
 
So, a quick general theory question.

If you have a 240v heating element wired up, touching each hot leg to neutral will be sitting at 120v(or whatever it actually is in reality).
Now, in terms of amperage, if that element is drawing 22 amps at 240v, is the load split between the two legs? That is, if you measure the amperage on Hot A, will it be 11 amps or 22?

I ask because my intention is to essentially build a stripped down version of Kal's panel with a 3 position switch for two 5500w 240v elements plus the ability to run a 120v 1200ish watt element at the same time as one of the 5500's.


I initially thought of this question when I was trying to figure out of a 30 amp relay could handle a 22 amp 240v load as well as a 120v 10 amp load. My thinking was that each leg would be handling 11 amps from the 240v element plus one leg handling an additional 10 amps from the 120v load.


Basically, I'm confused.
 
Now, in terms of amperage, if that element is drawing 22 amps at 240v, is the load split between the two legs? That is, if you measure the amperage on Hot A, will it be 11 amps or 22?

Current will not split between the 2 legs, it will be the same through the whole circuit so 22 amps will flow through one side and then out the other.
 
So, a quick general theory question.
...
Basically, I'm confused.

No worries man, if its a new concept and can be difficult to get your head around it.

Lets call the two hots L1 and L2 then the Neutral. if you measure voltage from L1 to L2 you will read 240V. To make it easier to understand, we'll treat it like a DC circuit, forget the AC stuff for now.

Imagine L1 has a voltage of 120V and L2 has a voltage of -120V, neutral has 0V.

if you measure from L1 to L2 you get 240, and if you measure from any L to Neutral you will get and absolute value of 120.

Now current is a measurement of volume, just like gallons of water in a flowing pipe. It's just a quantity of electrons, instead of gallons, it's amps.

So if you put a 'pipe' between L1 and L2 with a 'valve' (resistor) in it, it limits the flow. What ever electrons go into L1 (22A) will come out of L2. So Amps in = Amps out.

Put another 'pipe' between L1 and N with a different 'valve' between it. Electrons will flow from L1 to N, and what ever the volume is (10A) will come out Neutral.

So if you measure the current from L1 before it goes into the pipes to L2 and N, you will read 22+10A =32A;
If you measure the current flowing through Neutral it will be -10A (negative cause it is leaving).
If you measure the current flowing through L2 it will be -22A.
So, L1+L2+N = 32 + (-22) + (-10)=0;


This is over simplified, and not true to the actual mechanics but it helps demonstrate the concept of 'Goes ins' = 'Goes outs'
 
Very informative, thank you for the post. I'm new here, but have been brewing for about 18 years. I just rebuilt my basement and have a dedicated little room with a floor drain, stainless sink with sprayer, insulated fermentation box, 220V and gas line (as yet unused). I am very interested in building an automated system. I have the converted kegs and use those as mash tun, boil kettle/HLT with my turkey burners, just don't have to do it out in the garage any more. Just brewed an Oktoberfest ale and an American Amber with a twist - used San Francisco steamer yeast and fermenting at 70F instead of its usual lagering temp, ~45...but I digress.

I have an electrical engineering background and love to tinker (though not very mechanically inclined), so can't wait to tap the huge talent pool here and do some serious-ass brewing. If I can share some of my knowledge too, that'd be fun.

Jeff, SLC, UT
 
Very informative, thank you for the post. I'm new here, but have been brewing for about 18 years. I just rebuilt my basement and have a dedicated little room with a floor drain, stainless sink with sprayer, insulated fermentation box, 220V and gas line (as yet unused). I am very interested in building an automated system. I have the converted kegs and use those as mash tun, boil kettle/HLT with my turkey burners, just don't have to do it out in the garage any more. Just brewed an Oktoberfest ale and an American Amber with a twist - used San Francisco steamer yeast and fermenting at 70F instead of its usual lagering temp, ~45...but I digress.

I have an electrical engineering background and love to tinker (though not very mechanically inclined), so can't wait to tap the huge talent pool here and do some serious-ass brewing. If I can share some of my knowledge too, that'd be fun.

Jeff, SLC, UT
 
Sorry for double posting my last post, I don't know why there's a "Quick Reply" button and a "Post Reply" button...

I'd love to see some designs for the frame and plumbing works. I'll get into the control electronics later. Code RAge: do you know how to automate? RIMS, etc?

Thanks
 
Scut Monkey:
Ground and Neutral should never be tied together. A while ago it was kind of an accepted practice to use Ground as a neutral, now it is a major violation. If you have neutral bonded to ground any where they need to be separated. The bottom line is the ground conductor should only ever carry current in case of an emergency. Here is something to consider. Say you do have neutral and ground bonded at the device and for some reason the neutral gets disconnected some where else in the system. It should kill power to everything on that circuit. Well the device that has neutral and ground bonded will use the ground instead of the neutral and stay powered up. You know have steady current flowing on the ground through the circuit. Say there is a toaster on that same circuit and it's chassis is attached to ground, will that chassis now has current/potential flowing through it. If something should touch it with less resistance to ground (you are standing on a wet floor in the kitchen barefoot) it becomes the new path to ground and starts to carry all the current. I hope that illustrates the importance of it.

samc,
I added a device protection section, I'll revise it for SSRs here in a second.

dont know if this was already corrected, (didnt feel like reading 15 pgs) at your first point of service, ie comes from meter to either main panal or switch, your neutral and ground are connected. and this is the only point, at subpanals yes they are isolated. until they end back at the main. then they are bonded. just wanted to clear up if it already hasnt been done.
thanks
 
I feel like this primer is missing a very key component: What the heck is electric brewing?
 
I feel like this primer is missing a very key component: What the heck is electric brewing?

Um, I thought it was obvious :D brewing with electricity.
but to be clearer brewing with electrical hot water elements is the most common method.
 
Um, I thought it was obvious :D brewing with electricity.

LOL that was my initial thought. But then I read this primer and thought "I brew on an electric stove, why would anyone need all this information to do that?" :confused:
 
LOL that was my initial thought. But then I read this primer and thought "I brew on an electric stove, why would anyone need all this information to do that?" :confused:

Haha, that would have messed you up with so much talk about if you don't do it correctly you can kill yourself :D
Yeah the primer is more like a how to become a electrician for brewing applications.
 
I'll be moving into a much smaller space and am looking into an indoor all grain set up.

So far I'm planning to use a kettle on the stove top with a ~1500w 120v element to assist the stove.

From what I've read, I have to make sure the element is running on it's own 20amp circuit right?? How would I know if the outlets in the kitchen are on their own circuit?
 
I'll be moving into a much smaller space and am looking into an indoor all grain set up.

So far I'm planning to use a kettle on the stove top with a ~1500w 120v element to assist the stove.

From what I've read, I have to make sure the element is running on it's own 20amp circuit right?? How would I know if the outlets in the kitchen are on their own circuit?

Pretty much the only way you can tell is to plug something in (like a lamp). Then go hit the circuit breaker and see what it turns off.

Unfortunately, depending on how old the building is, you may find the entire kitchen on one circuit. Alternately you may find multiple circuits. It really depends on local code and how cheap the builder was when they ran the extra wire needed for the extra circuits.
 
I would like to set up a 10 gal biab setup using a 5500w element installed directly into a 20gal kettle.

Assuming L1 is connected to one side of the element, can i connect the second side of the element to a three way switch that would:
switch position 1 be left open so the element will be turned off
switch position 2 to be connected to neutral for 110v to allow me to run at 1400w for increasing mashing temp and keeping a boil
switch position 3 to be connected to L2 for 220v to get 5500w for boiling

I understand that all wiring must be rated for 30a (10 gauge) and both the element and switch should be grounded.

Would this work and be safe?
Would this work with a 220v GFCI breaker, or a GFCI inline power cable? my thoughts on the GFCI would be that since it is "listening" for amps on L2 and none exist, the gfci would trip when in switch position 2.
 
OD13, a three way switch is named deceptively. There are only two positions for the switch. Connected to one terminal or the other. If one terminal is off, the other can be connected to neutral, for 120V operation, or to L2 for 240V operation. If the panel is close enough to your rig you can use the 2P breaker as a means of disconnect, otherwise it'd be best to use a 2P 30A switch to turn the whole thing off. Maybe PJ will chime in here as well.
 
Assuming L1 is connected to one side of the element, can i connect the second side of the element to a three way switch that would:
switch position 1 be left open so the element will be turned off
switch position 2 to be connected to neutral for 110v to allow me to run at 1400w for increasing mashing temp and keeping a boil
switch position 3 to be connected to L2 for 220v to get 5500w for boiling

Sure, but consider this scheme. Assume you have a 10 Ω heater and a 120/240V feed. Connect one side of the heater to one of the phases. Connect the other side of the heater to the 'wiper' (common) terminal of a SP4T switch. Connect one position on the switch to the neutral through a diode. The neutral-phase voltage is 120V so the power developed would normally be (120^2)/10 = 1440 Watts but because of the diode current flows only half the time and when the switch is in this position the power delivered is thus half this or 720W.

Connect an adjacent position on the switch directly to the neutral (no diode in the circuit). The power delivered is the full 1440 W when the switch is in this position.

Connect a 3rd switch position to the other phase through a diode. The voltage from phase to phase is 240 V so normally the power delivered would be (240^2)/10 = 5760 W but as the diode restricts conduction to every other half cycle the power delivered in half that or 2880 W.

Connect the 4th switch position to the other phase without the diode. Now you have the full 5760 W. A fifth switch position could be connected to nothing to give you off. Thus you can have 1/8, 1/4, 1/2 and full.


I understand that all wiring must be rated for 30a (10 gauge) and both the element and switch should be grounded.
Yes


Would this work and be safe?

Don't see why not.

Would this work with a 220v GFCI breaker, or a GFCI inline power cable? my thoughts on the GFCI would be that since it is "listening" for amps on L2 and none exist, the gfci would trip when in switch position 2.

Yes it would. The GFCI is 'listening' to the currents on L1, L2 and the neutral. As long as the sum of those currents is 0, in other words as long as any current that flows to a load through, say L1, returns either through L2 or the neutral or a combination of L2 and the neutral as long as it all returns then the device is happy. If some of the current returns through another path (such as a ground fault) then the total through the GFCI is not 0 and it trips. Modern GFCI's also check to see that there is no path between neutral and the earth connector (except at the service entrance).

Now where you would get a SP5T 30 amp switch is another question. Arc welder part I suppose.
 
How would I know if the outlets in the kitchen are on their own circuit?

You could plug a lamp into every outlet you can find and then go to the panel and flip breakers until you find the one that turns off all or some of the outlets in the kitchen. This requires an assistant. "Did that do anything?", "No", "How about that?", "Yes, all the lamps on the island outlets went out".

The other approach, which is more expensive, is to get a current tracer. This is a little box that plugs into an outlet. You then take a probe unit to the panel and determine which breaker the outlet is connected to (the probe beeps when you put it adjacent to the relevant breaker). In this way you can map out the panel and the outlets connected to each breaker. Of course if the electricians did a good job that map already exists on the inside of the panel door. Not that I've ever seen one I could read or that was accurate if I could.
 
There a few ways to map out the electric in your house. One way you could find out which breaker controls what, sans assistant, is to use a similar approach as ajdelange said, but use a plug in radio instead (and extension cord if needed). When the radio goes off you note which breaker it is. Another is to turn off all the breakers, then turn on just one at a time (Double pole breakers don't count. They're usually hot water heaters, dryers, A/Cs, etc.) and see what's on. A small lamp or plug in radio to verify the outlets. It's a PITA, but it'll get the job done. It's also cheaper than hiring an electrican to do it for you.
"Of course if the electricians did a good job that map already exists on the inside of the panel door. Not that I've ever seen one I could read or that was accurate if I could." If it's a new house you should have a label inside the panel detailing what's where. Over time (some places don't require the electrician to label the circuits) other electricians and DIY'rs have added additional circuits or tapped existing circuits, without updating the label. So the label accuracy goes out the window. If you're going to label the panel, use generic terms; front bedroom, master bath, etc. This makes it easier to find than "Sally's room" if Sally moved out years ago. (steps off soap box...)
 
Another is to turn off all the breakers, then turn on just one at a time (Double pole breakers don't count. They're usually hot water heaters, dryers, A/Cs, etc.) and see what's on. A small lamp or plug in radio to verify the outlets....

Even easier than plugging in a radio is a non-contact voltage tester available at all home improvement stores and a lot less expensive than a current tracer. This does not need to be plugged in - just held near the hot of an energized circuit.

http://www.toolking.com/klein-ncvt-...&cagpspn=pla&gclid=CJ6-78vN4rMCFelDMgodBmYAZw
 
I'm new here an very familiar with electricity. I have to say your post is classic textbook and very well written. Thank you for your help.:mug:
 
I already have an opinion on this one, but thought I would throw it to those who know more. Is there a reason not to make an enclosure out of wood? I am going to leave this a very open ended question. I have already come up with various thoughts, but want to hear what you have to say. Thanks
 
I already have an opinion on this one, but thought I would throw it to those who know more. Is there a reason not to make an enclosure out of wood? I am going to leave this a very open ended question. I have already come up with various thoughts, but want to hear what you have to say. Thanks

Wood is flammable. If you have a loose connection on a 30A ckt, you can end up with enough heat to start things on fire. Happens every Christmas with frayed extension cords.

Use flame rated plastic or metal.
 
Even easier than plugging in a radio is a non-contact voltage tester available at all home improvement stores and a lot less expensive than a current tracer. This does not need to be plugged in - just held near the hot of an energized circuit.

http://www.toolking.com/klein-ncvt-...&cagpspn=pla&gclid=CJ6-78vN4rMCFelDMgodBmYAZw

klientester.jpg

I use one of these things. They work great.

Another use I've found for them is to test for spark on a spark plug wire (i.e., why isn't my lawn mower running).
 
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