Power Regulator For Electric Element

[itguy1953]

I am setting up a 50 litre SS insulated boiler to boil my wort and I am planning to install a 2400W electric element in the bottom of the boiler. I also have an electric immersion heater to use (in conjunction with the fixed element) to bring the wort to the boil quicker.

I am looking for a power regulator that I can use to turn the power down on the 2400W fixed element once I get the wort to the boil. This way I can change the speed of the boil, and also cater for smaller batch sizes.

Can you buy 2400W elements with inbuilt power regulators?

BTW, what is the maximum boil size that a 2400W element can handle in an insulated boiler.

Barry

 

[newguy]

What you're after is a PWM (pulse width modulation) circuit, which is a fancy way of saying something that pulses the element full power for a period of time, then turns it off for a different amount of time. If the element is full on (never off), then you have full power. If it's on for 20% of the time and off for 80%, then you are getting 20% of full power. All electric stoves have circuitry which will do this, but it will take a fair bit of jerry-rigging to get it up & running safely. You'll also need a stove to tear apart. I recommend that you get an electrician to wire it up for you once you've acquired all the parts.

 

[raven19]

+1 to newguy's reference

A 50L insulated kettle should be ok with 2400W.

I use 2 x 2400W, and got our 80L batch up to boil in about 20 minutes I think from memory.

If well insulated, 50L with 2400W should be fine. Bonus using immersion element also.

To control the boil, you could just adjust the amount of insulation (if using a camping mat or similar?) once boiling to get a good rolling boil, using a lid that is partially on can also help adjust boil rate if need be. This may be a cheaper option. Our kettle is just elements that are either on or off, switched manually. I like the idea of automation, but that will be much later on for me...

 

[kirem]

do a search on AHB for a sutronics burst fire controller.

It was I and many others use;

http://www.sutronics.com/acatalog/detail_bfm240_13.html

 

[itguy1953]

do a search on AHB for a sutronics burst fire controller.

It was I and many others use;

http://www.sutronics.com/acatalog/detail_bfm240_13.html

Thanks. Did you get a sparky to wire this up for you, or did you buy it ready to go.

I like the idea of having this controller mounted in a box with a male and female 3 pin pug on either side. I could then plug an extension lead from the power point into the male plug on the box, and plug the element plug into the female side. All sorted.

Any idea where I could get one made up, if you cannot buy them already made?

Barry

 

[RetsamHsam]

but then you'll need a male-male extension lead anyway, or at least a short male-male adapter lead.

That sounds like a dangerous option.. You wouldn't really want the pins exposed, there would be a massive risk of electricution, especially if you are sucking down some suds on brew day :excl:

 

[muckanic]

That sounds like a dangerous option.. You wouldn't really want the pins exposed, there would be a massive risk of electricution,

Excellent point, and I regret making the suggestion in the first place. Doing home electrics is bad enough without building in inherently unsafe design. I notice PCs and the like use recessed male plugs, but I don't recall ever having seen similar parts available in hardware stores. Maybe a specialist supplier?

 

[Crazy]

Muckanic

Even the recessed Male plugs go to the line end of the lead. Under no circumstances is it legal (or in any way not likely to kill you) to be able to get into a situation where the male end is live. As a sparky you do tend to look the other way a bit at non licenced work in home brewerys but this is a sure fire way to get your wife your life insurance pay out.

Chears Derrick

 

[muckanic]

Even the recessed Male plugs go to the line end of the lead. Under no circumstances is it legal (or in any way not likely to kill you) to be able to get into a situation where the male end is live.

The idea is that the recessed plug would form one side of the box housing the simmerstat. Here's a sanitised version of my original post:

My quicker 'n' dirtier effort is to house the simmerstat inside a plastic electrical junction box, with that box inserted in-line in the extension lead. So, you have to cut the lead and probably drill a hole or two in the box. I don't like the idea of having any junction box that is not waterproof too close to the boiler, and especially at floor level. Make sure the simmerstat is rated to at least 10 amps, and that everything is earthed. Another good bit of amateur sparky practice is to clamp the power cable so that there is no strain on the electrical terminals.

If you don't want to trash a dedicated extension lead, then as Barry suggests, it requires a box featuring a female socket on one side and a recessed male plug on the other.

 

[muckanic]

An afterthought on the element itself. Mine was raided from an old kettle, and served me in good stead for dozens of brews until I met my undoing on a roggenbier. I'd previously got away with numerous viscous weizens and wits, but the rye scorched. A lower density element, such as is found in hot water services, has less scorch potential. OTOH, many of them are 3600W which creates problems of handling 15 amps. There are workarounds, but I'm reluctant to say anything more at the risk of getting myself into hot water (pun intended).

 

[sid]

I'm using 1/2 a 180litr copper water cylinder which be the end with a 2k element and then adding a tap and wiring up a plug for my mash tun, the thermostat should be fine for this already as it goes up to 78 degrees... I'm going to keep the outside insulation on this as well so it keeps the heat.

Any one done this or heard of it?

 

[muckanic]

I'm using 1/2 a 180litr copper water cylinder which be the end with a 2k element and then adding a tap and wiring up a plug for my mash tun, the thermostat should be fine for this already as it goes up to 78 degrees

You will almost certainly be headed for scorching with that concentration of sugar. In the more fluid conditions of a kettle, an immersion element is a different matter. One thing I tried back in the distant past was a double-boiler arrangement for my mash-tun, which basically involved sitting a big aluminium stock-pot in a larger boiler. I deliberately went for aluminium over stainless because I wanted maximum thermal conductivity, as would also be provided by copper. The upshot of it is that I wound up chasing temperatures a lot, due to the lag between heating the jacket water and getting it to transmit. I did get to the point after some experimentation where I knew that if I heated up X L of jacket water to temperature Y, with a mash size of Z L, that I would hit my target temp in 10 mins or so. A number of folks running RIMS/HERMS seem to be forced into something similar.

Anyway, if you were to go the double-boiler route, you could easily scrounge a ceramic-lined steel hot water service for the outer boiler. These cut readily with an angle-grinder. Alternatively, I guess you could try and fit a false bottom in a mash-tun with element, but I suspect the sugar would still be as much a problem as the grains. I am wondering at this point whether a solid copper plate would transmit heat fast enough?

 

[pbrosnan]

I'd previously got away with numerous viscous weizens and wits, but the rye scorched.

That sounds weird. Having used and electric urn for over 70 brews I've never run into "scorching". As you say it is probably more to do with the viscosity of your wort and even then it must have been reaching the syrup stage. There's really no difference between brewing and cooking with regard to reducing a liquid via boiling and potentially burning it. In most cases it's very unlikely in brewing as the volume being boiling is quite large and you'd have to boil for a very long time to reduce it far enough. Perhaps you were doing small batches?

 

[sid]

Anyway, if you were to go the double-boiler route, you could easily scrounge a ceramic-lined steel hot water service for the outer boiler. These cut readily with an angle-grinder. Alternatively, I guess you could try and fit a false bottom in a mash-tun with element, but I suspect the sugar would still be as much a problem as the grains. I am wondering at this point whether a solid copper plate would transmit heat fast enough?

thanx for the reply, yeh I'll be putting in a false bottom for the mash tun, didn't think scorching here would be a problem as I only need to hit around 70c or so.
The boiler though Is where I will get the problems I reckon, might go a 3k element for this, but I have heard running that On household 240v wiring could be a problem..........might have to fuse it in case.

cheap enough to try all this as I had a spare cyclinder lying around

 

[choppadoo]

Temperature.com.au
At the bottom, the Variable Voltage Output SSR (TCSSRR2540 0hms 70 - 240VAC $62.00) works for me, although for a slightly different purpose. This unit mounted on an appropriate heatsink, will handle up to 40amp currents. For those in melbourne, their store is two doors down from grain and grape, and they were very helpful when i was sussing it out.

Cheers,
chops

 

[muckanic]

Using a potentiometer is not ideal from an efficiency perspective, due to all that power being wasted as heat. There are some applications where you don't want the element switching on and off, but I don't consider that to be a large requirement with beer.

 

[Thirsty Boy]

You dont need that "fine" a level of control..

Perhaps just have two 1000W elements and you can switch one off if needed.

I don't think there will be too great an issue anyway - I find that a roughly 2000W element scavenged out of the $12 kettles at coles/woolies is just about perfect for a rolling boil in a single batch (say a 25-30L starting volume) it takes a while to get up to the boil... but you have an immersion element to help with that. So the cheapest and dodgiest option - is in my books just about the perfect one.

The ability to dial the heat up and down would be nice to have... but I reckon it might be a feature you dont get as much value out of, as the trouble you have to go to in order to get it.

 

[Ducatiboy stu]

Thyristor with Phase-Loop-Lock control will be your ultimate answer, then you can set it to boil, then turn it down for sparge or mashing temps

 

[Brewbloke]

Hey guys, first post here. In the process of setting up SS 50L keg for a mash tun at the moment, first attempt. Basically my idea at the moment is to install the element(2400W immersable) under the false bottom. Element will be near recirculating drain spigot with the basic idea of pumping the heated water back through the mash.

For temp sensing, my idea was to place two immersable probe stats to gain a temperature differential from the top of the mash to the middle/bottom of mash. Stat probes will be mounted say 100 mm from top and 100 mm from the false bottom.

Stat probes will be hooked up to a Siemens(or equivelent) temp controller with deadband adjustment, providing a simple, accurate cut in/cut out point to switch the element(via a contactor).

PWM control or PID control would definitely work, but perhaps to over complicated for 25 litre batches?

Any thoughts or criticism's appreciated.

Dan.

 

[muckanic]

Any thoughts or criticism's appreciated.

Well, seeing you asked, there is a reason people go the RIMS/HERMS route. I would try a test run with the immersible element in a sugar solution of gravity approx 90. Scorch potential could depend whether we are talking intermittent high power or constant low power. Secondly, any thermostatically controlled, automated system probably needs a stirrer or some sort of recirculation.