Load safety on circuit

[sicktght311]

For you electric brewers out there with home electrical knowledge.........

Most electrical brew systems running on 120v utilize 1650watt elements, such as the Clawhammer system, advertising them as being able to run on a single 15amp household circuit. Which on paper, works......1650watts = 13.75amps on 120v, plus maybe half an amp for a lower power pump, and you're at around 14amps, on a 15amp circuit. Good to go. Stepping up to a 20 amp circuit, you could run a 2200watt element, as is sold by BrewHardware, at 18.3amps, plus small pump or two, and you're under 20amps. Good to go

However every electrical code out there requires 80% total load capacity, which means that 15 amp outlet is overloaded above 12amps, and you're running the risk of fire. 20amps you should run no more than 16amps. In theory then, none of this should be safe, and the only safe way to brew at 120v is on a 20amp circuit limiting your element size to 1650watts, and at 240v 5500 watts is maximum on a 30amp circuit.

So then who here brews on a 15amp circuit, with 1650watts, or a 20 amp circuit with a 2000-2200watt element, and have you had no issues with things heating up? I've been brewing on my system with a 1650watt element and 2 small pumps (1x DC, 1x AC, both pull no more than .5amps together), DIY controller with 12awg wiring, plugged into a 20amp circuit with a 25ft 12/3 extension cord and the cord and outlet never been warm to the touch at all. My HLT element recently died, and i decided it was a good opportunity to upgrade to a 2200watt element, and move my 20amp outlet closer so i dont have to use the extension cord anymore. But now i'm second guessing whether i'm introducing a fire hazard running at more than 80% load capacity on a 20amp circuit for 2+ hours at a time while water heats up and boils

 

[Deric]

This has come up often here. The 80% max is for "continuous use".

 

[sicktght311]

This has come up often here. The 80% max is for "continuous use".

Yeah the NEC's definition of "Continuous Use" is 3+ Hours at 100% power. A typical 120v brew day is 2-2.5hours total heat up time at 100% output, mash for an hour, 30ish minutes for mashout, and then around 1.5hours between boil ramp up time, and 60 minute boil. So it never truly runs at 3+ hours continuous.

So by definition, its not really exceeding that benchmark, but at the end of the day, is 2 hours safe vs 3+ hours ya know? Does that hour make a difference, or are we realistically talking that you're probably fine even at 3hours, but dont leave it running all day long

 

[Homebrew Harry]

If you only had one dedicated outlet on a 20A circuit I would not worry running over the 80% by so little. That's without any extensions. 12 guage wire to the outlet must be fused at 20A, but could handle 25A. Just not legally or safely.

 

[Beerstein]

If you only had one dedicated outlet on a 20A circuit I would not worry running over the 80% by so little. That's without any extensions. 12 guage wire to the outlet must be fused at 20A, but could handle 25A. Just not legally or safely.

I bought a 10 awg extension coord for those longer wee heavy boils just to be safe. It's typically only an extra $20.

 

[sicktght311]

If you only had one dedicated outlet on a 20A circuit I would not worry running over the 80% by so little. That's without any extensions. 12 guage wire to the outlet must be fused at 20A, but could handle 25A. Just not legally or safely.

Yeah the current setup is the 1650watt element on a 12awg extension cord into a 20amp outlet
New would be 2200watt element, no extension cord, right into a 20amp outlet on 12/2 wiring about 10ft to the main service panel on a 20amp breaker. GFCI outlet of course

 

[Homebrew Harry]

Yeah the current setup is the 1650watt element on a 12awg extension cord into a 20amp outlet
New would be 2200watt element, no extension cord, right into a 20amp outlet on 12/2 wiring about 10ft to the main service panel on a 20amp breaker. GFCI outlet of course

Also some outlets are made better than others. If this is an existing outlet I would check to see if the house wiring was wrapped around the screws and not just stuck in those speedy holes. Maybe replace it with a heavy duty one bought at a real hardware store.

 

[Homebrew Harry]

I bought a 10 awg extension coord for those longer wee heavy boils just to be safe. It's typically only an extra $20.

Yeah those are nice. I have some big ones also, but if at all possible don't use an extension. At every connection there is a little resistance that is cumulative to the circuit.

 

[sicktght311]

Also some outlets are made better than others. If this is an existing outlet I would check to see if the house wiring was wrapped around the screws and not just stuck in those speedy holes. Maybe replace it with a heavy duty one bought at a real hardware store.

I'm replacing it myself. It was an old outlet that i'm moving, and replacing with a 20amp GFCI receptacle wrapped around the screws. So i'm confident in the connections since i will have done them myself

 

[Homebrew Harry]

Is this outlet dedicated ? If not, other appliances downline will overload your circuit if turned on.

 

[sicktght311]

Is this outlet dedicated ? If not, other appliances downline will overload your circuit if turned on.

Yes it is the only outlet, on a dedicated 20amp circuit.

Main Service Panel 20 amp breaker -->10ft of 12/2--->GFCI 20 amp outlet

Thats it

 

[Homebrew Harry]

Yes it is the only outlet, on a dedicated 20amp circuit.

Main Service Panel 20 amp breaker -->10ft of 12/2--->GFCI 20 amp outlet

Thats it

That's great. If it were me I would make sure the 3 connections in the panel were tight also[after turning off the main disconnect.]
My Son had an outlet for a toaster that quit working. The neutral had been arcing in the panel on the bus. I'm 99.9% sure it had not been tightened properly the day it was installed.

 

[sicktght311]

After all of these replies, i think i'm gonna load up the HLT with 7 gallons of tap water tonight, and run it for a couple of hours to test heat up times, but also keep an eye on the wiring and temps. If everything is nothing more than lightly warm after a couple hours, then we should be good to go. Good opportunity to test the heatsink temps on my SSRs as well with the increased 4.5amp load

 

[Homebrew Harry]

After all of these replies, i think i'm gonna load up the HLT with 7 gallons of tap water tonight, and run it for a couple of hours to test heat up times, but also keep an eye on the wiring and temps. If everything is nothing more than lightly warm after a couple hours, then we should be good to go. Good opportunity to test the heatsink temps on my SSRs as well with the increased 4.5amp load

Good luck. All should be well. If not, we'lI have to rip rhat 12g outa there ! ... I have a length of 10g out in the shop

 

[PCABrewing]

At every connection there is a little resistance that is cumulative to the circuit.

A common place to notice heating, even when used within the load limits.
And once the female terminals heat they sometimes loose their temper and aggravate the problem.
Less spring leads to less connection that leads to more heating.

 

[Deadalus]

Yeah the NEC's definition of "Continuous Use" is 3+ Hours at 100% power. A typical 120v brew day is 2-2.5hours total heat up time at 100% output, mash for an hour, 30ish minutes for mashout, and then around 1.5hours between boil ramp up time, and 60 minute boil. So it never truly runs at 3+ hours continuous.

So by definition, its not really exceeding that benchmark, but at the end of the day, is 2 hours safe vs 3+ hours ya know? Does that hour make a difference, or are we realistically talking that you're probably fine even at 3hours, but dont leave it running all day long

This isn't an answer to the last part but cumulative is not the same as continuous.

If you are concerned about the draw, and since you are moving the outlet, you could just put in a 30 amp (single pole, 120V) circuit breaker. Wire it with 10 gauge. You might have to buy 10/3 and just not use the red wire, particularly if you were to use armored cable, whatever is available though. You could put a regular 20 amp outlet on it or a 20 amp GFCI on it. There's probably a proper 20 amp plug you should use vs. a standard home 120V plug. My whole house is wired 20 amp and all the plugs can accept the different 20 amp plug but nothing you buy normally is really ever 20 amps except shop equipment so I don't actually have anything with that plug in the house. One blade will be sideways (horizontal). I do have wiring above 20 amps for the stove, water heater, etc.

The 80% rule is for the breaker itself isn't it? But you might have old wiring and the cost for what I am suggesting isn't at all that much and you are moving it anyway.

 

[Deadalus]

Thinking about it further though, if you were to do what I just said, just go big and put in a 30 amp 240 line! It's pretty much the same amount of work except you would need to cover the GFCI at the breaker most likely and you need an additional slot in the panel. Ok maybe a little more involved as you might need to move around some wires in the panel because the current breaker probably doesn't have an open spot next to it.

Well then you need a controller too, so this suggestion is a bit of a rabbit hole potentially.

 

[PCABrewing]

Thinking about it further though, if you were to do what I just said, just go big and put in a 30 amp 240 line! It's pretty much the same amount of work except you would need to cover the GFCI at the breaker most likely and you need an additional slot in the panel. Ok maybe a little more involved as you might need to move around some wires in the panel because the current breaker probably doesn't have an open spot next to it.

Well then you need a controller too, so this suggestion is a bit of a rabbit hole potentially.

240-30a is more efficient for sure. My table saw is much more lively on 240, up to speed as fast as you throw the switch. Not that it's important but it handles heavy loads better too. You could get by with 20a, but of course having higher capacity is always nice.

 

[sicktght311]

Thinking about it further though, if you were to do what I just said, just go big and put in a 30 amp 240 line! It's pretty much the same amount of work except you would need to cover the GFCI at the breaker most likely and you need an additional slot in the panel. Ok maybe a little more involved as you might need to move around some wires in the panel because the current breaker probably doesn't have an open spot next to it.

Well then you need a controller too, so this suggestion is a bit of a rabbit hole potentially.

Haha yeah the rabbit hole'ness of going to 240 keeps me from going to 240 until i'm ready to upgrade my brewing capacity. Once i wanna go bigger than 5 gallon, i'll likely retrofit my panel to 240, and wire in a 30amp 240 line.

For now, sticking with 120v, i'm trying to avoid running all new wiring from the panel, so i'm gonna see how well this works, and hopefully everything will be no problem

 

[PCABrewing]

Haha yeah the rabbit hole'ness of going to 240 keeps me from going to 240 until i'm ready to upgrade my brewing capacity. Once i wanna go bigger than 5 gallon, i'll likely retrofit my panel to 240, and wire in a 30amp 240 line.

For now, sticking with 120v, i'm trying to avoid running all new wiring from the panel, so i'm gonna see how well this works, and hopefully everything will be no problem

Don't forget to add the steam hood blower into your final calc.

 

[sicktght311]

Don't forget to add the steam hood blower into your final calc.

Lol D'oh! haha all of this is coming as i'm beginning to rebuild my basement brewery too, moving from one side to the other, so i'll save the larger purchases/revisions for later on after all of that is done hah

 

[Deadalus]

The original suggestion I made is a 30 amp, 120 volt line. It would need a breaker like this. Which if you use 10/3, you'd be future proofing the move to 240V as long as you went with 30 amps there as well. Sounds like you might just be extending the line from the current junction box and outlet? In some jurisdictions, if you are adding another outlet, that's considered new work, in which case the whole branch needs to be upgraded. If you are running the line from the panel itself, the only extra step is the new breaker which would fit in the current spot. You would need a slightly larger box probably for the outlet vs a 15 amp most likely, but I just do that anyway to have the space for the GFCI.

 

[KyBeer]

I built an electric system 10 years back, 240v 60A main service. This was a logical power selection for me because the parts required are available at most hardware stores. Hot tub GFI's are lower cost than GFI breakers. I can run my HLT and BK both at the same time when doing a double brew day, (5200W elements). I can also run a water recirculation pump on the HLT and a Wort pump for transfer or continuous sparge at the same time.

I have found the cost difference of upgrading to a higher power level as compared to the cost of you brewing system is very small. 25-foot of 14/2 vs 12/2 is normally less than 3 dollars. Going larger also provides for expansion in the future.
My biggest challenge was ventilation. With two 15-gallon kettles running I get a lot of steam. The last thing you need is mold in your home. A low-cost range hood didn’t cut it. Used an 8-inch vent with an inline high CFM fan.

Built to what fits your needs within your budget. I have never regretted going over spec on the power.

 

[sicktght311]

Update here. Ran a water test with the new elements on the moved outlet, and it seems we're good to go. The heatsink on the controller was no warmer than it was when running the 1650watt elements, and the plug and 12/2 wire to the panel was barely warm. Going to run a full brew day either this weekend or next week, and I'm confident now it should be good. Panel was reading 2100 watts actual draw at 18.3amps.

Side note, the heat up time was SIGNIFICANTLY quicker with the 2200 watt element vs the 1650 watt

 

[Homebrew Harry]

Side note, the heat up time was SIGNIFICANTLY quicker with the 2200 watt element vs the 1650 watt

Yeah, I bet it was quicker !
I'm glad you got it going

 

[T Murph]

@KyBeer your system sounds like what I am in the process of building. I acquired a like new 1500 cfm commercial Wolf vent hood. I want a controller that has the capability of running everything including the exhaust hood. The Brew Buddy is close but it only has two 110 outlets for pumps. I need something that will also turn the exhaust fan on and off with the BK element. I'm looking for suggestions.

 

[GilSwillBasementBrews]

@KyBeer I want a controller that has the capability of running everything including the exhaust hood. The Brew Buddy is close but it only has two 110 outlets for pumps. I need something that will also turn the exhaust fan on and off with the BK element. I'm looking for suggestions.

If you’re a DIY type I am in the middle of building a panel myself and went with the dprs320 ezboil from Auberins as my controller. It has programmable alarm states you can use to to trigger relays to power additional devices. You could look into that.

 

[Bobby_M]

@KyBeer your system sounds like what I am in the process of building. I acquired a like new 1500 cfm commercial Wolf vent hood. I want a controller that has the capability of running everything including the exhaust hood. The Brew Buddy is close but it only has two 110 outlets for pumps. I need something that will also turn the exhaust fan on and off with the BK element. I'm looking for suggestions.

It seems slick to tie the vent hood to something like the Boil Element Enable switch, but what if you want to run the hood for 15 minutes longer than the boil?

There really isn't any plug and play controller out there with a 3rd switched aux outlet.

 

[Bobby_M]

Yeah the NEC's definition of "Continuous Use" is 3+ Hours at 100% power. A typical 120v brew day is 2-2.5hours total heat up time at 100% output, mash for an hour, 30ish minutes for mashout, and then around 1.5hours between boil ramp up time, and 60 minute boil. So it never truly runs at 3+ hours continuous.

So by definition, its not really exceeding that benchmark, but at the end of the day, is 2 hours safe vs 3+ hours ya know? Does that hour make a difference, or are we realistically talking that you're probably fine even at 3hours, but dont leave it running all day long

Breakers are designed to carry their rated load indefinitely. The 80% load rule is for hard wired fixtures such as water heaters. There aren't that many residential examples outside of that. However, you're using a branch circuit with a portable plug. If it's a 20 amp receptacle, 12gauge wire, and a 20 amp breaker. You can run 20 amps for as long as you want.

If you're really interested in cutting your brew day time down, a pair of 1650 elements or a 1650 and a 2250 would blow your mind.

 

[T Murph]

It seems slick to tie the vent hood to something like the Boil Element Enable switch, but what if you want to run the hood for 15 minutes longer than the boil?

There really isn't any plug and play controller out there with a 3rd switched aux outlet.

Running the exhaust longer than the element is a definite requirement. I'm just thinking outside the box looking for a way to automate the vent hood. Hoping someone on here knows of a trigger activated by steam or a simple temperature switch to turn it on and off via set perimeters. Else I gotta turn it on and off manually or use a separate controller just for the fan.

 

[Tom R]

Running the exhaust longer than the element is a definite requirement. I'm just thinking outside the box looking for a way to automate the vent hood. Hoping someone on here knows of a trigger activated by steam or a simple temperature switch to turn it on and off via set perimeters. Else I gotta turn it on and off manually or use a separate controller just for the fan.

You can use a timer like this to set a run time after the element is shut down.
GAEYAELE GRT8-A1 B1 Delay Off Time Relay Electronic 16A AC230V OR AC/DC12-240V with CE CB Certificate(GRT8-B2,AC/DC12V-240V) - - Amazon.com

 

[T Murph]

You can use a timer like this to set a run time after the element is shut down.
GAEYAELE GRT8-A1 B1 Delay Off Time Relay Electronic 16A AC230V OR AC/DC12-240V with CE CB Certificate(GRT8-B2,AC/DC12V-240V) - - Amazon.com

Thanks @Tom R this just might be the ticket.

 

[JAReeves]

I love the technical details that many of you were able to add to this thread. I have no issues with my 220/3500W induction burner, but I have discovered that only certain power strips can handle the 120/1800W induction burner at full power without overheating the strip and tripping the fuse/breaker. I had no idea about the load maximums you all have put up here, but it makes sense now why certain stuff doesn't work in my brewery.

 

[sicktght311]

Breakers are designed to carry their rated load indefinitely. The 80% load rule is for hard wired fixtures such as water heaters. There aren't that many residential examples outside of that. However, you're using a branch circuit with a portable plug. If it's a 20 amp receptacle, 12gauge wire, and a 20 amp breaker. You can run 20 amps for as long as you want.

If you're really interested in cutting your brew day time down, a pair of 1650 elements or a 1650 and a 2250 would blow your mind.

Thanks Bobby! And you're correct, the combination of a 1650 and a 2200 is probably exactly what i'll do when my next upgrade bug hits. I've been thinking of moving to 15 gallon kettles, triclamp fittings, and utilizing 2 TC fittings for elements. One for the 2250 that will always be connected to the controller, and then another one that i can load a 1650watt element in if i want to brew 10 gallon batches, or capped off whenever i'm brewing 5 gallon batches. I like the idea of having the power be convertible based on the size i'm brewing, still using the controller i built, and just having the 1650 watt element for the added oomph.

Now if they only made 15 gallon kettles with bottom drains. Grrr haha

 

[sicktght311]

I love the technical details that many of you were able to add to this thread. I have no issues with my 220/3500W induction burner, but I have discovered that only certain power strips can handle the 120/1800W induction burner at full power without overheating the strip and tripping the fuse/breaker. I had no idea about the load maximums you all have put up here, but it makes sense now why certain stuff doesn't work in my brewery.

1800 watts is just about maxing out if not actually overloading a 15amp circuit, so that totally makes sense. 120v is not actual voltage in the US. Depending on time of day and your house and area, that can be anywhere from 105 to 120volts actual. So if you're pulling a full 120volts, you're right at 15amps, the max capacity of the circuit. However if you're pulling in 110volts, which is fairly common, you're now pulling 16.36 amps, over the rated capacity of that circuit.

All that being said, thats assuming the wattage is consistent and true at 1800. My 1650 watt elements actually read closer to 1500 watts power draw on my volt/amp meter in my brewing controller. The 2200 watt elements are reading closer to 2100

 

[itsnotrequired]

1800 watts is just about maxing out if not actually overloading a 15amp circuit, so that totally makes sense. 120v is not actual voltage in the US. Depending on time of day and your house and area, that can be anywhere from 105 to 120volts actual. So if you're pulling a full 120volts, you're right at 15amps, the max capacity of the circuit. However if you're pulling in 110volts, which is fairly common, you're now pulling 16.36 amps, over the rated capacity of that circuit.

All that being said, thats assuming the wattage is consistent and true at 1800. My 1650 watt elements actually read closer to 1500 watts power draw on my volt/amp meter in my brewing controller. The 2200 watt elements are reading closer to 2100

restive loads like a heater don't work this way, power output drops as voltage drops. assuming element rated 1800 watts at 120 volts, looking at something a bit over 1500 watts output at 110 volts or around 13.75 amps.

 

[doug293cz]

restive loads like a heater don't work this way, power output drops as voltage drops. assuming element rated 1800 watts at 120 volts, looking at something a bit over 1500 watts output at 110 volts or around 13.75 amps.

Correct. If P = power in watts, I = current in amps, V = voltage, and R = resistance in ohms, then the following describe the relationships among the values:

V = I * R​

I = V / R​

R = V / I​

P = I * V​

P = I^2 * R​

P = V^2 / R​

R = V^2 / P​

The two bold formulas can be combined and/or rearranged to give the others.​

​

A heating element is a fixed value resistor. An element rated at 1800W @ 120V, means that it will produce 1800W if the applied voltage is 120V. The resistance of such an element is:

R = V^2 / P = 120^2 / 1800 = 8.00 ohms​

This resistance will not change as the applied voltage changes, but the power (and the current draw) will. Power at various input voltages will be:

P @ 120 V = 120^2 / 8.00 = 1800 W​

P @ 115 V = 115^2 / 8.00 = 1653 W​

P @ 110 V = 110^2 / 8.00 = 1513 W​

P @ 105 V = 105^2 / 8.00 = 1378 W​

The currents drawn at different input voltages will be:

I @ 120 V = 120 / 8.00 = 15.00 A​

I @ 115 V = 115 / 8.00 = 14.38 A​

I @ 110 V = 110 / 8.00 = 13.75 A​

I @ 105 V = 105 / 8.00 = 13.13 A​

​

Brew on

Edit: Correct last four formulas as they are for current (I), not voltage (V).

 

[KyBeer]

@KyBeer your system sounds like what I am in the process of building. I acquired a like new 1500 cfm commercial Wolf vent hood. I want a controller that has the capability of running everything including the exhaust hood. The Brew Buddy is close but it only has two 110 outlets for pumps. I need something that will also turn the exhaust fan on and off with the BK element. I'm looking for suggestions.

I didn't run my fan or the lights through my brew system. As an engineer I always looked for the single point of failure. Redundant power equals higher reliability. I also built a waste water transfer system because a drain was not close by. My next project is a fermentation chamber. My wife repurposed my Keezer as a freezer, (pandemic bulk purcheses) and I don’t have room for another freezer.
Are you following a plan or design for your build?

 

[T Murph]

I didn't run my fan or the lights through my brew system. As an engineer I always looked for the single point of failure. Redundant power equals higher reliability. I also built a waste water transfer system because a drain was not close by. My next project is a fermentation chamber. My wife repurposed my Keezer as a freezer, (pandemic bulk purcheses) and I don’t have room for another freezer.
Are you following a plan or design for your build?

No I am not building my controller myself. Yet, that is. I'm not that electronically savvy. But I may end up doing so with the help of experts on here.

 

[sicktght311]

Ran a full brew day last night. Heat times significantly quicker, and i was able to boil 7.25 gallons without the cover on with a gentle rolling boil. Cover slightly on (maybe covering half the kettle) was a good strong boil. All the wiring, controller, etc all performed well and was only slightly warm to the touch. Should be good to go from here out. I was running around 2100 watts at 115volts