Wiring an L6-30R for 110v output

[Jcruse]

For all of you running 5500 watt elements at 110v (which would result in 1375 watt output), how are you wiring them? I'm building out 2 control panels for a Brewha BIAC I just ordered, and planned on having 1 dedicated "Brew" controller with 220v output to the element, and a separate "Fermentation" controller that only would output 110v to the element for heating for diacetyl rests/winter fermentation (which I will limit even further to just 10% duty cycle with the pid to avoid scorching the yeast).

Since my element will have a L6-30p plug on it, I was going to just wire a L6-30r receptable for 110v for the fermentation controller. I'm assuming I would just wire the neutral to X or Y on the receptacle, but does it matter which one, and is that the correct way to supply 110v to a 220v element?

 

[lschiavo]

Plugs/receptacles are configured differently so they do not accidentally get connected to the wrong power source. Polarity does not matter for an element and the L6-30 will work just fine. As long as you do not foresee any problems with mixing up your plugs, you should be fine.


If you want to keep things separate, the proper plug to use is a L5 for 120V.

 

[BeardedBrews]

In this case the risk is eliminated by the use of a 5500w element so regardless you couldn't over-volt the element.

JCruse, you could actually wire two L6-30R into the same control panel. Wire one with both hot legs as normal, and the other you just use the one hot leg from the SSR and bring neutral across to the third pin.

This saves on parts and time spent wiring.

 

[Jcruse]

In this case the risk is eliminated by the use of a 5500w element so regardless you couldn't over-volt the element.

JCruse, you could actually wire two L6-30R into the same control panel. Wire one with both hot legs as normal, and the other you just use the one hot leg from the SSR and bring neutral across to the third pin.

This saves on parts and time spent wiring.

My original design was a single panel, but with only the 240v L6-30p outlet. I would then limit the element's duty cycle to ~2-3% to prevent the yeast scorching potential during fermentation. But I decided to breakout the fermentation control to a separate box, so my brew controller wouldn't be tied up if I decided to expand to a 2nd BIAC.

 

[lschiavo]

My original design was a single panel, but with only the 240v L6-30p outlet. I would then limit the element's duty cycle to ~2-3% to prevent the yeast scorching potential during fermentation. But I decided to breakout the fermentation control to a separate box, so my brew controller wouldn't be tied up if I decided to expand to a 2nd BIAC.

I would build the dual controller. If you get another BIAC, build a second one. You can cover every possible scenario that way with the least number of controllers.

 

[dyqik]

Bobby_M (and some others) has built a RIMS controller with a 5500W element that can switch between 230 and 115 V with a single receptacle.

You need to switch (with a break-before-make type switch) between the neutral and one hot leg to one of the contacts of the element receptacle, with the SSR on the other leg.

You might want to also put an SSVR (maybe with a switchable fixed resistor to set it to a fixed low level?) or fast PWM power controller on the control side, to limit the peak power of the element, as the fastest cycle on one of the typical PID controllers used in controllers is around 2 seconds, in which time a 1375W element can heat a fair bit in still wort/fermenting beer, even at 10% maximum duty cycle, particularly if trub, yeast and CO2 bubbles have settled on it during fermentation. It's probably better/a little safer to limit the peak power as much as possible in the "on" part of the cycle than to limit the maximum duty cycle.

 

[Jcruse]

Bobby_M (and some others) has built a RIMS controller with a 5500W element that can switch between 230 and 115 V with a single receptacle.

You need to switch (with a break-before-make type switch) between the neutral and one hot leg to one of the contacts of the element receptacle, with the SSR on the other leg.

You might want to also put an SSVR (maybe with a switchable fixed resistor to set it to a fixed low level?) or fast PWM power controller on the control side, to limit the peak power of the element, as the fastest cycle on one of the typical PID controllers used in controllers is around 2 seconds, in which time a 1375W element can heat a fair bit in still wort/fermenting beer, even at 10% maximum duty cycle, particularly if trub, yeast and CO2 bubbles have settled on it during fermentation. It's probably better/a little safer to limit the peak power as much as possible in the "on" part of the cycle than to limit the maximum duty cycle.

I was planning to limit the output using OUTH on the auber pid. According to their documentation:

OUTH can be used when you have an overpowered heater to control a small subject. For example, if you set the OUTH = 50, the 5000 watt heater will be used as 2500W heater (50%) even when the PID wants to send 100% output.

Will that still allow 100% output for short durations?

 

[BeardedBrews]

Will that still allow 100% output for short durations?

As far as I know, the output from that unit will be 100% with a 50% duty cycle. The reality is that the element doesn't go from cold to hot instantly, so it may be functionally the same.

Reducing the input voltage would certainly be the safer approach.

This would be even safer:
http://www.reptilebasics.com/12-heat-tape

 

[dyqik]

I was planning to limit the output using OUTH on the auber pid. According to their documentation:

OUTH can be used when you have an overpowered heater to control a small subject. For example, if you set the OUTH = 50, the 5000 watt heater will be used as 2500W heater (50%) even when the PID wants to send 100% output.

Will that still allow 100% output for short durations?

Yes. The PID connects to an SSR, which only allows the power to be on or off. So at 100% demand, with OUTH = 50%, and a 2s cycle time (I think that's the minimum for Auber PIDs) the power is 100% on for 1 second, and off for 1 second. SSVRs or fast PWM systems like the Auber DSP thingy can reduce the power on a per AC cycle basis, and so the maximum power to the element is actually reduced at all times.

Whether that 1 second of full power is enough to cause problems in a fermentor with a 1375W (5500W/4) element, I don't know, but it seems possible that it would stress any yeast that's settled on the element enough to throw off flavors that may be noticeable. The problem is that the wort/beer in a fermentor is still, and trub and yeast is settling all the time.