50 amp electric brewing panel OCPD

[jlash630]

I am in the process of designing a 50A panel and looking at the primary over current protection needed in my home panel... Here's where it gets fun... The two big names in the DIY/Pre built panel market, call these 50amp panels and say you just need a 50A breaker.. Well, after consulting the NEC book, the brew panel could be considered a "continuous load" (A load where the maximum current is expected to continue for 3 hours or more), given that I would be heating the strike water in the BK while the HLT is heating up.. the BK would be off for a little while while we are mashing, but as soon as the sparge starts, the bk element will be back on... 1 hour sparge, 30 minutes to heat up, 1 hour boil.. I feel we are tip toeing the line here on whether or not the panel breaker should be upsized to a 60A GFCI (which stinks, because they are not nearly as common as a 50A) due to the continuous load definition...

Granted an OCPD is rated to run at 100% capacity indefinitely without tripping if the load is by definition non-continuous..

What are you guys and gals seeing your panels draw when both elements and both pumps are running?

My design will incorporate some 4-20mA loops for flow and possibly density as well as a future 3rd pump to be possibly used as a BK condenser. This puts me right around a calculated current draw of 54A if everything was running at once..

 

[staffordj]

I don't think you will ever run both elements at full power for 3 hrs. Once you are up to temp on the hlt,, it won't need much to maintain the temp. Once you are boiling you should not need to heat the hlt.

 

[Bobby_M]

Even though your HLT will technically be actively heating to keep the sparge water hot when you start heating the boil kettle, the element will barely be blipping at an aggregate 5% output at most. The only case where you'd be pushing your luck is if you do a true back to back turnaround by refilling the HLT and heating that while you're still in the middle of a boil.

 

[jlash630]

Even though your HLT will technically be actively heating to keep the sparge water hot when you start heating the boil kettle, the element will barely be blipping at an aggregate 5% output at most. The only case where you'd be pushing your luck is if you do a true back to back turnaround by refilling the HLT and heating that while you're still in the middle of a boil.

That make sense, however... I pulled this directly from Kais website...

"50A Electric Brewery Control Panel for back to back batches: For producing up to 20 gallons of finished product per batch. A single element is used in the boil kettle and hot liquor tank, but both may be run at the same time allowing you to boil one batch while heating water for the next (or for cleaning/heat sanitizing the chiller."

With my current gas setup, I am actively heating fresh water in the HLT to clean the MT while I'm coming to boil.. I do this to keep busy and lessen the clean up at the end.. granted this would only be one of the two pumps.. but if I purchase the submersible pump for the condenser, we have two pumps running.. or I'd have two pumps running while heating strike water in the kettle and the HLT at the beginning..

I suppose it's not an issue with their panels, as they don't have the added load of a 24vdc power supply (roughly 2.1 amps at full load. I'm estimating my PS won't be loaded that much..)

This one reason I asked if you could share what you see the panel drawing during heat up or boil (if you're actively heating clean up water)...

In my line of work, everything is over engineered and over sized with safety factors built in.. it followed me home

 

[doug293cz]

If you run the two pumps from opposite hot legs of the 240V supply, then the total current will be the same as if you are only running one pump. Do the same with your DC power supply (assuming you feed it with 120V) and a third pump, and the load on the 240V wires is the higher of the two, and the difference flows thru the neutral line. This will cut a few amps off of your total load.

I would also look at the timing estimates for heating your planned water volumes to temperature. You will only be drawing full power (and current) in an element when you are actively raising the temp of the liquid in the vessel. I find it hard to believe that you would run both elements at 100% for 3 overlapping hours.

Brew on

 

[superiorsat]

60A GFCI

Amazon is about the only place to get your hands on a 60 Amps GFCI at an almost reasonable price. Homedepot, Lowes, and Menards have been out forever. I would say just get the 60 Amp so you can proceed with out making sure you have employed enough conservation techniques or that you may have to limit what you can turn on at the same time. Just my 2 cents.

 

[Deadalus]

I'm not sure which scenario you believe is the highest draw but one of them will be. I am not sure how this might work with a RIMS I only have HERMS.

Sparging with the BK on-Here, your PID is only going to be cycling the power on and off. You will have already reached your sparge temp and need to just maintain it.

Sparging done, reheating HLT, boiling wort-I roughly have about 5 gallons of water left in the HLT after sparging. My HLT is a keggle with a HERMS coil. That's for a 6 gallon batch. I've got some room over the coil that I don't fill to as it allows me to add some water. This is system and batch size dependent. Your next set of water for your HLT won't be groundwater cold however. The wort going into the BK will be somewhere under sparge temp but still hot. I don't normally set the power at 100% in the BK when I turn it on because I don't know the level that it might scorch at exactly. So I let the wort cover the element some and turn the power on to ~85-90%. Once it boils, I turn the power down. I check in every 15 minutes and watch the boil off amount and most times continue to drop the power. I'm typically down at 25-30% the last 15 minutes. I like to keep it running higher in the beginning to make sure I don't need to boil longer but you could fine tune an average % and it won't be 100. Even if you jammed it up to 100% while still sparging and trying to get it to boil, it won't be long after you are done sparging that your wort will be boiling. Won't be anywhere near 3 hours before you get the HLT to temp again or the wort to boil.

Heating HLT, BK heating strike water-The amount of strike water won't be as much as in the HLT. The strike water is going to need to be around 20F more tops? Even brewing a double batch size (max size for me), I would only have roughly 2/3 of the water for strike water vs the HLT. I don't think the strike water in the BK will ever take longer to heat than the HLT. However, again, once one reaches its temp, the PID is going to only send power sporadically or you will turn down the power on the BK. If it even took the BK a little longer, that's not going to be 3 hours.

I don't think your scenarios ever could exceed 3 hours.

 

[ITV]

You didn't state the watt of the heating elements or the size of the brew vessels, but I agree that both elements will not be on 100% for 3 hours.

Regarding the 60 amp breaker panel, that requires an upsize in wire from the 50 amp panel. A consideration if the wire to the breaker panel is existing.

 

[Bobby_M]

That make sense, however... I pulled this directly from Kais website...

"50A Electric Brewery Control Panel for back to back batches: For producing up to 20 gallons of finished product per batch. A single element is used in the boil kettle and hot liquor tank, but both may be run at the same time allowing you to boil one batch while heating water for the next (or for cleaning/heat sanitizing the chiller."

With my current gas setup, I am actively heating fresh water in the HLT to clean the MT while I'm coming to boil..

One person did mention the importance of knowing vessel sizes and intended batch sizes. If you're boiling 12 gallons, the boil kettle element (assuming 5500 watt) will be running at about 75% output for about 18 amps of average draw once it gets boiling. That leaves plenty of headroom for a 100% output into the HLT. The other thing we can't know is maybe you have plenty of headroom in the HLT that you can heat an extra 5 gallons than you need for the sparge and be left with already hot water for cleaning.

 

[Mad Mann]

If you are building your own panel and intend on running two elements simultaneously, I suggest making sure there is adequate air flow internally for cooling. If it gets too hot inside the panel you will risk premature failure of some of your electrical parts.

 

[doug293cz]

If you are building your own panel and intend on running two elements simultaneously, I suggest making sure there is adequate air flow internally for cooling. If it gets too hot inside the panel you will risk premature failure of some of your electrical parts.

The majority of the heat generated in a panel is from losses in the SSRs. The other components generate very little heat. The exception may be a DC power supply inside the enclosure - it depends on the power output and efficiency of the power supply. For example a 100W output power supply that is 90% efficient will generate about 11 W of heat (100 / 0.9 - 100.) SSRs can generate 20 - 35 W each.

Usually, if you have adequately sized external heat sinks, and the SSRs are mounted directly to the heat sinks (thru enclosure cut-outs), you don't have to worry about enclosure venting or fans.

Brew on

 

[jlash630]

You didn't state the watt of the heating elements or the size of the brew vessels, but I agree that both elements will not be on 100% for 3 hours.

Regarding the 60 amp breaker panel, that requires an upsize in wire from the 50 amp panel. A consideration if the wire to the breaker panel is existing.

The vessels are 15g Spikes, the elements will be 5500W ULWD, as far as wiring, I intend on running 6awg THHN from my main panel, which is de-rated to 65A when its wired to 75C connectors. Since it sounds like we will be under the 3hr time limit, leaves me with plenty of headroom..

 

[Ozarks Mountain Brewery]

you should be fine with 15 gallon kettles, your elements wont stay on that long

 

[jlash630]

The majority of the heat generated in a panel is from losses in the SSRs. The other components generate very little heat. The exception may be a DC power supply inside the enclosure - it depends on the power output and efficiency of the power supply. For example a 100W output power supply that is 90% efficient will generate about 11 W of heat (100 / 0.9 - 100.) SSRs can generate 20 - 35 W each.

Usually, if you have adequately sized external heat sinks, and the SSRs are mounted directly to the heat sinks (thru enclosure cut-outs), you don't have to worry about enclosure venting or fans.

Brew on

According to the spec sheet, the PS is 87% efficient. The SSRs will indeed be mounted directly to a large heatsink, I am going to use the same one from the electric brewery. The panel is a 24x20x8 Hoffman.

 

[doug293cz]

According to the spec sheet, the PS is 87% efficient. The SSRs will indeed be mounted directly to a large heatsink, I am going to use the same one from the electric brewery. The panel is a 24x20x8 Hoffman.

What is the max output wattage of the PS?

Brew on

 

[jlash630]

What is the max output wattage of the PS?

Brew on

90W, it's going to power two panel indicators, two 4-20mA transducers, and possibly 2, 1/2" mag meters.

 

[jlash630]

Here's the flow meters..
https://www.ifm.com/us/en/product/SM6000
I'm tired of having to babysit sparge flows

 

[jlash630]

In the end, those will get replaced with some 1/2" micromotions..

 

[jlash630]

I am estimating that with all 24v items the PS will be loaded roughly 30-33W

 

[doug293cz]

90W, it's going to power two panel indicators, two 4-20mA transducers, and possibly 2, 1/2" mag meters.

Ok, that's 90 / 24 = 3.75 A max output current. Max input power would be 90 / 0.87 = 103.5 W, or 103.5 / 120 = 0.87 A @ 120V, or 103.5 / 240 = 0.44 A @ 240V. Heat output into the enclosure would be max 103.5 - 90 = 13.5 W.

Brew on

 

[ITV]

My design will incorporate some 4-20mA loops for flow and possibly density as well as a future 3rd pump to be possibly used as a BK condenser. This puts me right around a calculated current draw of 54A if everything was running at once..

I believe that you are using 220V in your calculations, 240V is the nominal voltage (120V x 2).
As doug293cz mentioned you can connect your pumps on opposite legs (assuming they are 120V) to balance out the current draw which should keep you below the 50A draw @240V with everything running.
Since you plan on running 6AWG cable you have the option to design a 60A panel, however you are below the 50A threshold.

 

[Deadalus]

I snapped a picture of my panel when I was sparging. It's a 30 amp panel. I waited and let the wort cover the element deep then put the BK on 100% while both pumps were running. The panel was drawing 21.16 amps.

 

[kal]

If you are building your own panel and intend on running two elements simultaneously, I suggest making sure there is adequate air flow internally for cooling. If it gets too hot inside the panel you will risk premature failure of some of your electrical parts.

Better yet, put the heatsink(s) outside. That's what I do on my panel (and my designs) as I want them to be more or less sealed so that they're water resistant. Some of these panels have been running 2-3 brews/day for years. Cheers!

Kal