I ve put off responding to this, hoping more experienced power controllers would chime in, but here goes. The best control for a resistive load (like a heatingMessage 1 of 64 , Jul 1, 2010View SourceI've put off responding to this, hoping more experienced power controllers would chime in, but here goes. The best control for a resistive load (like a heating element) is an active electric controller. In this case, "active" means that one of more solid-state electronic devices (like SCRs, SSRs, or TRIACS) are used to switch load current off and on very quickly, so quickly that power seems continuous.
An inactive controller would be a variable resistor (rheostat or potentiometer) or variable transformer (VARIAC). Controlling power by varying resistance is hugely energy-inefficient, and variable transformers can be very expensive and large.
Thing of an active controller as a light-dimmer on steroids. They can be self-built fairly easily, if you have those skills and a good design, or they can be purchased as specialized distilling electronics from people like our own Pint-O-Shine (you still out there, Pint?), or you can purchase router speed controllers from woodworking tool suppliers.
While I know what makes good controller electronics, I have no experience with any of these. Some designs will be better than others, and current ratings must always be considered, but, from what I've seen, I'm guessing that Pint's controller is one of the best. Note that Pint's controller is rated at 40A, twice the current of most router controls. Perhaps for reasons of availability outside the US, many distillers use one of the Sutronics controllers.
Link to Pint's controller Link to Harbor Freight router controller Lint ot Amazon.com controllers Link to Sutronics controllers.
Zymurgy Bob, a simple potstiller
--- In Distillers@yahoogroups.com, "thursty2" <thursty2@...> wrote:
> --- In Distillers@yahoogroups.com, "geoff" jeffrey.burrows@ wrote in part:
> > I would always stick with my old tried and trusted method of two separately (2500watt and 850 watts) plugged elements and manually plugging in each as and when it's needed.
> > Geoff
> Couple of questions Geoff, Are you running Pot or Reflux. How many litres of wash are you boiling off in one hit, and once you switch to the 850 watt element, do you finish the boil with it, or do you have to switch the 2400w element back on?
Funny you should bring this up at this time, Geoff. I ve just been digesting the information from the 2 ethanol-water mixture density tables that Harry sentMessage 64 of 64 , Jul 9, 2010View SourceFunny you should bring this up at this time, Geoff. I've just been digesting the information from the 2 ethanol-water mixture density tables that Harry sent me, and in the process, looking at my hydrometer and alcoholometer. While Waldo and Harry have covered all the important parts in depth, let me put some of this in some practical forms.
First, my hydrometer can measure densities from .990 to 1.170 g/cm^3, reading from the internal paper scale. In addition, doing some serious guesstimating, it appears that at densities below .950 g/cm^3 the hydrometer will sink to the bottom of the measured liquid.
Similarly, my alcoholometer measures (also on the internal paper scale) densities from .789 to 1.000 g/cm^3, amd looks to sink at any density less than about .774 g/cm^3
If we look at the density range where both instruments can serve as sugar-concentration hydrometer or ethanol-concentration alcoholometer, the range shared betweenthe 2 instruments is from 1.000 to .990, which means that the hydrometer (if you had some conversion from density to %ABV like the tables Harry sent me) could read ethanol concentrations form 0-7% ABV, and the alcoholometer could measure sugar concentrations from 0 to 0% (since all sugar-water solution must have a density greater than 1.000, even if an FG of .994 is common in wine).
Further, because after the hydrometer can still move downward, even after the liquid level is above the readable paper scale, at about 41%ABV, the hydrometer will sink to the bottom of the test jar and can not register (and sure as hell can not read) ethanol concentrations greater than 41% (a guess, but close).
So, at least with my instruments, you could use the hydrometer, with conversion tables, to crudely measure %ABV from 0-7, and my alcoholometer will give you no reading with any sugar solution.
If you're wondering why I dwell on the sinking instrument, it's because I started a spirit run with my hydrometer in my parrot beak, and the hydrometer did not lift at all when the beak overflowed. Starting ABV was probably 78-80.
I hope this helps.
Zymurgy Bob, a simple potstiller
--- In Distillers@yahoogroups.com, "geoff" <jeffrey.burrows@...> wrote:
> Hi Jim,
> I 'm not trying to be nit pick Jim but it has always bothered me why ner' the twain will do for the same job although in a different way, if you know what I mean