10/4 cord to 10/3 contoller

[pickled]

I have a 10/4 twistlock extension cord, but my Still Dragon DYI controller and heating element are 10/3 conductor. I intend to install a twistlock connector on the supply side of the controller.
I have instructions for the SD controller, but not sure how to wire it if its supplied by 10/4.

[acfixer69]

The 10/4 wire has a white (neutral) which is not need with the SD controller.

[pope]

It's a great place to store 10/4 cord if you think you'll need it later. Just ignore the white/neutral wire and use the three you need.

[pickled]

Thanks guys!

[ShineonCrazyDiamond]

The white cord is there so you can add a 120v amp meter or 120v fan. I recommend the computer fan highly.

[pope]

You could also use the neutral to run a 30a 240v gfci breaker (they're ~$100), but then you can't use the neutral for any 120v load or the imbalance between the two poles will give you a ground fault and trip the breaker.

[pickled]

Could the neutral support an ammeter and cooling fan? If so, could you point me to a schematic?

Thanks again!

[Expat]

Could the neutral support an ammeter and cooling fan? If so, could you point me to a schematic?

Thanks again!

Yes.... They would be wired from black (or red but not both) to the white to make a 120v leg. Additional devices would be wired in parallel to that leg. No issues of capacity here. You could wire in a toaster and it wouldn't make a difference.

Or you could just have an analog ammeter and wire it inline with the hot going to the SSR.

[RedwoodHillBilly]

You could also use the neutral to run a 30a 240v gfci breaker (they're ~$100), but then you can't use the neutral for any 120v load or the imbalance between the two poles will give you a ground fault and trip the breaker.

Of course you can. If you trip the breaker due to leg imbalance you wired it wrong. The common mistake I see from those who don't know how these breakers work is to tie the input neutral to the output neutral. The input neutral is generally a white pigtail and the output neutral is a screw terminal.

[pope]

The common mistake I see from those who don't know how these breakers work is to tie the input neutral to the output neutral. The input neutral is generally a white pigtail and the output neutral is a screw terminal.

WHAT?! That's immensely useful for me. I definitely wired mine wrong by connecting the two. While we're at it how would you connect the neutral to the still to trip the GFCI correctly?

[RedwoodHillBilly]

The common mistake I see from those who don't know how these breakers work is to tie the input neutral to the output neutral. The input neutral is generally a white pigtail and the output neutral is a screw terminal.

WHAT?! That's immensely useful for me. I definitely wired mine wrong by connecting the two. While we're at it how would you connect the neutral to the still to trip the GFCI correctly?

Use your output L1, L2, N as required by your load(s). Connect the input L1, L2, N to your power source. Don't mix the two. Ground (Protective Earth) is common as this is a nonconductor except in a fault condition. If you are still confused, use your Google Fu. There are plenty of diagrams pertaining to spa/hot tub wiring.

[Tennessee_Spirits]

It is easy to connect a 4 wire cord to a 3 wire one, but not the other way around. The function of the neutral wire is needed only if you desire now or later to derive 120 volts to power pumps or elements. The neutral wire is the center tap on the power transformer to your home and it carries current and has a voltage drop if there is asymmetry in the load on a 240 volt main breaker. The safety ground should never be connected to the neutral tap as this can produce significant voltage at high current capability to pots and other metal appliances and metal tables.

The NEMA L6-30 is used commonly enough in brew elements that I made it standard for 240 volts for my brewing because it is rated for 30 AMPs and heating elements are plentiful with the male connector on the kettle. This means that cleaning is not complicated by a trailing cord. 30 amps at 240 volts is 7,200 watts and to my opinion this is enough for a hobby. Elements with male L6-30 connectors are available from 2000 to 5500 watts.

The NEMA L6-30 is a 3 wire plug. It is sweet having the neutral wire in a controller for 120 volt pumps and such. I've not really missed having neutral because fans and DC supplies are available for 240 volts because of the widespread use of switching supplies. I have a controller for 240 and a second one for 120 volts.

Larger set ups with 50 AMP input and interaction controls need a neutral lead. The ideal connection for larger controllers is clearly with a 4 wire connector such as the L14-50 which is bigger physically and handles 50 AMPs with neutral wire provided. I have no immediate plans for such a set up as it is large for hobby use.

I think the important decision is how many watts need to be used at the same time. I had a single outlet 120 volt circuit installed when I had my garage rewired for this and that circuit powers my RIMs heater. If I go to a 240 volt RIMs heater I won't be able to heat the sparge water at the same time and would need a second 30 amp circuit! Many houses are wired with 100 AMP main panels and 60 AMPs for brewing may be over the top.

Remember that electrical codes usually require that a continuous load be no greater than 80% of the beaker size. This limits the 30 AMP circuit effectively to 24 AMPs and a 5500 watt element draws 23 AMPs.

What I call interaction controls are circuits that automatically stop heaters if there is no flow or the element is exposed. I've seen beer controllers that won't allow the element on without a pump turned on. I've not found this level of automation cost effective for a hobby but wouldn't it be nice if we had better/cheaper level sensors and flow rate sensors. But every sensor you attach complicates maintenance and cleaning.