Electric Brewery's

[Scott H]

We spoke about creating a discussion so people who have or people who are thinking about and/or building can share pic's info and pitfalls to avoid.

Just about finished building my bench and hopefully will have a chance to start wiring it up this weekend. Pics to follow shortly.

[Druid]

The sparky I used said to use a lower figure for the voltage when doing this sizing calculation. I can't quite remember 100% but think it was 220v - it may even have been 200v that he recommended though.

In any case, the lower figure is needed in case the mains voltage drops which will result in more current flowing to satisfy the power demand of the element which remains constant, regardless of the voltage ie. your circuit will end up being asked to carry more current.

5500/220 = 25A

Lower voltage in the mains is apparently quite common.

[Andrew Graham]

Actually the current will be less. The element is rated 5500W at 240V. If you put less voltage in the current will also be less assuming the element has a fairly constant resistance.

Also, if you are only getting 200V to your appliance there is probably some real heat being generated in the cables inside your walls. A good sparky would choose a cable that would not drop 30V under full rated load.

[Peter Smith]

Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance,^[1] one arrives at the usual mathematical equation that describes this relationship:^[2]

where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms. More specifically, Ohm's law states that the R in this relation is constant, independent of the current.

Temperature of the element will change the resistance slightly but boiling occurs at 100C not likely to change as the voltage in your house may.

[Druid]

So, if R is constant and V changes, then I must change to satisfy the equation. Or is there something I'm missing re. my first post?

Edit - ok, now I see that I will change in accordance with Ohms law, not to maintain watts = amps x volts - hence the current will drop.

[Peter Smith]

Yeah this is first year electrical eng trick question Druid..... the rated wattage is only at rated voltage.....   but they always throw that kinda question into the mix to test if you understand the basic laws of physics cant change.

When cabling I would always have a bit of overhead in the cables ability to run for a short period above the expected load.  For me for this situation a 30amp breaker would be a suitable solution and I would also install an RCD.   

I have just purchased  5500w elements,  I am going to wire the circuit for 40amps so I can have a standard 10amp socket and a big heavy duty socket off the same breaker and RCD, that way my entire setup is through an RCD.   Both 10amp HLT and the 5500w heater off the same breaker.

[Hamish Jones]

Does anyone know where to get a stainless socket with the correct thread for the 5500w camco elements in NZ and is it 1" NPS

I am going to weld them to my pots then screw them in

[Hamish Jones]

Ok after some working out of amperage required to do what I need an all electric system isn't going to work for me unless I completely rewire the garage, what I am going to use is 100L HLT, 100L Mash Tun and 150L kettle

So what I am going to do is use an element that draws less than 15 amps and use a gas burner to help with it to ramp temperatures, now if I just run two relays off the PID one for a solenoid to fire the gas and one for the element that should work or do I need to do something more tricky,

Thinking if I do it this way and use a 40 plate heat exchanger as a herms then I don't need an extra element in the mash tun so I can get away with two smaller elements in the HLT and kettle supplemented by gas and not have to rewire the place,

What's the thoughts on that those who are more brainy than I?

[Barry]

Plate heat exchanger for HERMS is very brave, two possible consequences:

1. You'll get crap from the mash in it – bits of grain and husk
2. You'd potentially be mixing pre-boil and post-boil wort, risk of contamination especially as plate chillers can be hard to clean. See above about crap from the mash.

My opinion, if you have to mess around with solenoids you might as well go with 100% gas?

Do you really need such a big system? I have a system that yeilds a shade under 80l of fermented beer, but that's because it's shared between 5 thirsty guys (thus my other thread about 150l pots – we ideally want to get 5 full 20l kegs out of it).

My electric system at home is a 30l system. Everything is so much easier at that scale.

[Hamish Jones]

Good points was just thinking plate heat exchanger to save building a herms thingy but an extra shiny stainless object won't go astray, 

was thinking Gas/Electric combo as my existing setup the gas burner always overshoots temp with heat soak from the thick pot base so with electric as well it should keep the temp a bit more consistent as the gas won't be firing all the time

When I built my BIAB rig with a 60L pot I thought all good that'll be big enough for anything I want to do and now I am really pushing it's boundaries so I kind of wish I started bigger, and the fact I got 100L pots with 4mm bases for $80 each off trade me I thought why not and I am doing a bit of brewing with a friend and we split batches so it makes life easier to go bigger.

[Scott H]

Using PiDs to control gas valves provides a whole new set of issues not to mention costs.

[Peter Smith]

Barry - Have you tasted many Grainfather beers yet?  Just wondering 3 vessel vs Grainfather/Braumeister style, do you think that the 3 vessel produces a better tasting/scoring beer, brewing skills being equal....

[Barry]

I haven't, that I recall specifically though I've tasted many biab and single vessel system beers and plenty of 3 vessel beers.
By far the greatest number of faults in any competition I've judged were fermentation faults. I'd be quite prepared to say that's what everyone should focus on well over and above how much stainless bling they've got.
I went with tricked out stainless bling because I wanted to make my brew day easier and more controlled, and wanted to add chilling into my process. I slummed it for 5 years with 5l jug transfers and ghetto hard-to-clean vessels and plastic fermenters. Made some great beer and some not so great. Wort can be made pretty easily using the most rudimentary setup.
But I totally expect that if I don't get the fermentation right it won't matter how pretty my system is.