Load safety on circuit

[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

 

[Homebrew Harry]

Should be good to go from here out. I was running around 2100 watts at 115volts

It sure seems like you are good to go. It looks like you have the circuit loaded to almost 92%, but since it is a dedicated circuit and you are on site I don't see any problem. I almost asked you to look at the rating on your GFCI outlet, but you said it was already installed.
I'm glad it is working and staying cool.

 

[sicktght311]

It sure seems like you are good to go. It looks like you have the circuit loaded to almost 92%, but since it is a dedicated circuit and you are on site I don't see any problem. I almost asked you to look at the rating on your GFCI outlet, but you said it was already installed.
I'm glad it is working and staying cool.

What rating are you referring to? Its a 20amp GFCI Eaton outlet. Wired directly to the screw terminals (not the push in fire hazards)

 

[Homebrew Harry]

What rating are you referring to? Its a 20amp GFCI Eaton outlet. Wired directly to the screw terminals (not the push in fire hazards)

That's it. Good deal !

 

[sicktght311]

That's it. Good deal !

Lol oh yeah. If i went through all this conversation and talk, only to put a 15amp breaker in, i would deserve whatever happened hah. I installed the outlet myself. It was a random single outlet tucked away in my drop ceiling that i never even know was there until we had to renovate the basement. Probably was at one time for an air conditioner or a dehumidifer or something. So once i confirmed it was 12/2 wiring, and traced it back to the breaker confirming it was the only outlet on the line, i knew it was good for a dedicated brewing outlet. Just needed to replace with GFCI and i was good to go

 

[Homebrew Harry]

Lol oh yeah. If i went through all this conversation and talk, only to put a 15amp breaker in, i would deserve whatever happened hah. I installed the outlet myself. It was a random single outlet tucked away in my drop ceiling that i never even know was there until we had to renovate the basement. Probably was at one time for an air conditioner or a dehumidifer or something. So once i confirmed it was 12/2 wiring, and traced it back to the breaker confirming it was the only outlet on the line, i knew it was good for a dedicated brewing outlet. Just needed to replace with GFCI and i was good to go

That's a happy coincidence there was a dedicated circuit already there whatever it was for.

 

[jseyfert3]

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.

120 volts is very much the actual voltage in the US, and is specified by ANSI C84.1. Range A in the standard (or what is the normal voltage) specifies a service voltage of 120 volts plus or minus 5%, so an in-spec unloaded residential voltage is 114-126 volts. There is a range B that allows service voltages to drop as low as 110 at the very lowest, but events causing voltage to be in range B must be limited in extent, frequency, and duration. In other words if they occur frequently the utility is required to correct things to get the voltages back to the 114-126 volt spec. There is no allowance for a service voltage of 105 volts.

I think the lowest unloaded voltage I’ve ever seen has been around 117 volts. Normally it’s plus or minus a couple volts from 120, as it should be.

Now, it’s certainly possible to see the loaded circuit voltage drop below 110, if you have a heavy load and a lot of voltage drop, but 110 is an abnormal voltage to see at an outlet in the US barring this. In the spec the absolute minimum voltage anything in your house should have when fully loaded with maximum NEC allowed voltage drops and the minimum of the range B service voltage (which again is not normal) is 104 volts. And this is very, very much an edge case. Devices are likely to start having issues here, especially motors.

Sorry, got on my soapbox there, a pet peeve of mine when people say the standard voltage in the US is not 120 volts, because that very much is the standard voltage in the US.

 

[itsnotrequired]

Sorry, got on my soapbox there, a pet peeve of mine when people say the standard voltage in the US is not 120 volts, because that very much is the standard voltage in the US.

this is due to individuals misinterpreting the phrase "standard" to mean as "constant", just a nomenclature thing. also note that range a 114-126V applies to the service voltage or the voltage at the service point (typically the meter socket for residential applications). voltage regulation downstream of the service point falls on the user (homeowner). as you indicate, heavy loads can drop local voltage but can also be caused by long conductor runs, say to a detached structure a significant distance from the service point. so even though the service entrance may be to spec, a remote building may not be.

 

[Homebrew Harry]

this is due to individuals misinterpreting the phrase "standard" to mean as "constant", just a nomenclature thing. also note that range a 114-126V applies to the service voltage or the voltage at the service point (typically the meter socket for residential applications). voltage regulation downstream of the service point falls on the user (homeowner). as you indicate, heavy loads can drop local voltage but can also be caused by long conductor runs, say to a detached structure a significant distance from the service point. so even though the service entrance may be to spec, a remote building may not be.

^Yes Sir. Also, I have noticed that voltage drops on long runs won't show themselves fully until a load is applied

 

[doug293cz]

^Yes Sir. Also, I have noticed that voltage drops on long runs won't show themselves fully until a load is applied

Well, you only get voltage drops when there is current flowing. The wires are resistors, and the longer and thinner the wires the higher the resistance (R). Ohms law gives the relation between voltage drop (V), current (I), and R:

V = I * R​

Thus if I = 0, then V must also = 0.

Brew on