# Electrical gurus needed, 11000 watt electric

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Planning some electrical upgrades to accompany a larger electric still. I'll be purchasing the materials and need some input. Unit will be heated with 2 5500 watt 240 volt elements.

Looks like total line run will be about 55 feet. Do I use a 6/3 wire and a 50 amp double pole GFCI breakers or does this require a 60 amp breaker?

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For sizing a breaker the math is 11,000/240 = 45.8333 then you need a safety factor of 25% minimum 45.8333*1.25=57.2917 then round up to the next size breaker 60. https://www.hunker.com/12291117/how-to-size-a-circuit-breaker

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The description on that controller is vague and its hard to tell exactly what is in the cabinet. It looks to be SCR maybe, but the critical component would seem small. You need to know your true utilization voltage. You are at 53 amps on 208V, and 46A on 240V. Max continuous load on a 60A breaker is 48 AMPS. I would get a Master Electrician's take on it. #6 Copper THHN is rated for 75A.

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Two 5500 watt 240v single phase elements fed 208v single phase power, draw 40 amps and only put out 8,262 watts.  Because the elements are 240v being fed 208v, dividing 11000 by 208 gives an incorrect answer.  The math is a  more complex than that.  Anyway 40 amps x 1.25 = 50, so a 50 amp breaker or fused disconnect works fine in that 208v power feeding two 240v element scenario.

Of course if the 240v elements  are being fed 240v power, then dividing 11,000 by 240 does give you the correct answer, as long as the power supply is single phase.  If you are feeding the single phase 240v elements 3 phase 240v  you get a much lower amp draw.

To answer the OPs question.  If your input voltage is 240v single phase then you need a 60 amp breaker and the 6 gauge wire is fine.

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Starcat,

I just checked and the controller is one of mine.  We have upgraded to a different enclosure and some slightly different components since that pic was taken but the breakers and SSRsare the same capacity as the controller in the picture  There is nothing small about this controller.  We have sold thousands of them and they work great.  On these controllers, one element has on off control and the other has proportional control.  The element with proportional control has a variable SSR with pentameter.  Both the variable SSR and the SSR are good for 40 amps which is more than needed. Unlike most of our competitors these controllers do not have vents and cooling fans that could draw in ethanol vapors so these controllers are safer.  The enclosures are NEMA4.  What is the primary component that you believe to be too small?  This type of controller is for direct fired electric stills not baine marie stills.

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It was just hard to tell where the SCR was located and the contactors were prominent, so hard to know exactly what was inside. It did not look bad, just hard to tell what exactly it was from an industrial perspective. I am talking SCR which is not the same thing as SSR.

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2 hours ago, Southernhighlander said:

Two 5500 watt 240v single phase elements fed 208v single phase power, draw 40 amps and only put out 8,262 watts.  Because the elements are 240v being fed 208v, dividing 11000 by 208 gives an incorrect answer.  The math is a  more complex than that.  Anyway 40 amps x 1.25 = 50, so a 50 amp breaker or fused disconnect works fine in that 208v power feeding two 240v element scenario.

Of course if the 240v elements  are being fed 240v power, then dividing 11,000 by 240 does give you the correct answer, as long as the power supply is single phase.  If you are feeding the single phase 240v elements 3 phase 240v  you get a much lower amp draw.

To answer the OPs question.  If your input voltage is 240v single phase then you need a 60 amp breaker and the 6 gauge wire is fine.

Paul - I did go with the assumption that OP was single phase and yes the math is slightly more complex if it is three phase.

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Thank you guys, confirmed my assumptions that I needed a 60 amp breaker. Appreciate the insight

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4 hours ago, starcat said:

It was just hard to tell where the SCR was located and the contactors were prominent, so hard to know exactly what was inside. It did not look bad, just hard to tell what exactly it was from an industrial perspective.

I understand, No problem.

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2 hours ago, sandytoes said:

Paul - I did go with the assumption that OP was single phase and yes the math is slightly more complex if it is three phase.

I was going back to starcats assertion   "You are at 53 amps on 208V, and 46A on 240V"

I was referencing the math to figure the amp draw and the output of two 5,500 watt 240v elements being fed with 208v single phase power.  Because the elements are

240v and the single phase power supply is 208 in his scenario,the math to figure out the wattage and amp draw is very complex.  Calculating the amp draw of 3 phase 240 volt feeding the single phase 240v elements is just slightly more complex: 11,000/(240x1.73)=amp draw.  If using single phase elements on 3 phase power it is best to have 3 elements, 6elements,9 elements or 12 elements becouse th load will be more balanced if the single phase elements are wired in sets of 3, however if the load is slightly out of balance becouse there are 4 or 8 sibngle phase elements powered with 3 phase,it is no big deal. It is common to have single phase elements in 3 phase heating systems.

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