How would you build a 240v controller that can power a 9kw element?

[Windy City]

Hey bcook sorry did not mean to pee on your parade just trying to look out for you.
There are several safe work arounds to get you up and running.
1)Check to see if your home wiring is in conduit. If it is you might be able to have a electrician pull wire from the circuit breaker box with a true neutral
2)Add a low voltage transformer that goes from 240volt to 24 or 12 volt, ac or dc and change your accessories to the corresponding low voltage.
3)Change your accessories to 240volt
Options 2 and 3 will probably be your least expensive, otherwise you will also need to replace your 50' cord to a 4 wire
Please be safe

[Windy City]

Hey bcook
I just did some reading and found some good news.
The DSPR100 can be run on 240 volt and does not need a neutral.
https://www.auberins.com/images/Manual/ ... ual_V1.pdf
Auber also offers a volt ammeter that will not need a neutral
https://www.auberins.com/index.php?main ... cts_id=490
This fixes your problems about a neutral
You could even get 240 volt fans should you decide to put some cooling in your box ( recommended )
I would spend the time to rewire your cords so they are properly color coded Green = Ground
This should all work out for you now.
Happy and Safe distilling

[Ben]

Adding a separate ground seems reasonable, rather than buying a whole new extension cord and updating the houses wiring structure. You can ground directly to copper water plumbing in the kitchen if it's handy, that way if something goes hot it will go through the ground and trip the breaker rather than going through your body, or the puddle you are standing in.

The better answer would be to install something like a spa panel with a GFCI breaker built in, maybe in the bedroom closet, run the ground directly to it. Hooked up properly that will give a lot of safety to the project, you would only need to build a short 4 wire cord that way. And the spa panel can still plug in to the kitchen outlet you are already using.

I know it sucks to rewire a fresh project, but being confident in it is worth something. Easier to learn from mistakes than successes.

[Windy City]

Adding a separate ground seems reasonable, rather than buying a whole new extension cord and updating the houses wiring structure. You can ground directly to copper water plumbing in the kitchen if it's handy, that way if something goes hot it will go through the ground and trip the breaker rather than going through your body, or the puddle you are standing in.

The better answer would be to install something like a spa panel with a GFCI breaker built in, maybe in the bedroom closet, run the ground directly to it. Hooked up properly that will give a lot of safety to the project, you would only need to build a short 4 wire cord that way. And the spa panel can still plug in to the kitchen outlet you are already using.

I know it sucks to rewire a fresh project, but being confident in it is worth something. Easier to learn from mistakes than successes.

He does not need a neutral and he already has a ground
He really only needs three wires if you read my post above

[shadylane]

Adding a separate ground seems reasonable, rather than buying a whole new extension cord and updating the houses wiring structure. You can ground directly to copper water plumbing in the kitchen if it's handy, that way if something goes hot it will go through the ground and trip the breaker rather than going through your body, or the puddle you are standing in. .

There's rules against doing that also.
More than one plumber has been electrocuted.

[zach]

This thread has alot of back and forth and just wanted to make sure I understand.

1) If you have a 10-50P 3-Prong Old Range outlet, and no 120 V required in the controller, the third wire (neutral or ground ?) is bonded to the ground in the circuit breaker panel. The third wire acts as a ground. But without a GFCI, you are not protected.

2) If you have a 10-50P outlet and your controller requires 120V, then a four wires are required. It is possible to use something like this for an adapter.

https://acworks.com/products/rv10501450 ... 968e&_ss=r

I have a 50 amp spa GFCI panel that I want to hook up to a 10-50P outlet and my controller will not require any 120V. The ground from the heating element / kettle will be connected to the controller then to the gfci panel then to the outlet.

Is there any advantage to use option 2 above with the fourth wire, when no 120 V is required?

[TwoSheds]

bcook,

I seriously hope you have abandoned this thread to seek qualified, licensed advice, but in case you haven't...

The only person with the right info here is quadra. Your outlet has two hots and a neutral to provide either 240 or 120v power. Quadra pointed that out. As proof I point you to this from a well known and respected manufacturer:

https://www.leviton.com/en/products/5050

The diagram may seem ambiguous, but the graphic in the instructions is not.

Your electric box and kettle should be grounded to the breaker box. You also need to make sure all your wiring in the path from the plug to the heating element is suitable for a 50a load.

Once you get your meter powered with 240v you should get a wattage reading that matches the amps*volts. I suspect that's just a calculated value in the display. The meters like that I've seen and used should be powered right off the mains, so make sure you're not powering it off the SSR.

If you don't want to tell an electrician you are a distiller (probably wise) just tell them it's for beer brewing equipment. If you don't have a column or condenser around they probably won't think twice about it.

Be careful!

TwoSheds

[TwoSheds]

This thread has alot of back and forth and just wanted to make sure I understand.

1) If you have a 10-50P 3-Prong Old Range outlet, and no 120 V required in the controller, the third wire (neutral or ground ?) is bonded to the ground in the circuit breaker panel. The third wire acts as a ground. But without a GFCI, you are not protected.

The third wire is a neutral. It acts similar to a ground in a short-circuit situation in that it will allow a ton of current through therefore tripping the breaker, but it has to be wired to the right pieces of metal to protect someone which a neutral typically isn't.

2) If you have a 10-50P outlet and your controller requires 120V, then a four wires are required. It is possible to use something like this for an adapter.

https://acworks.com/products/rv10501450 ... 968e&_ss=r

I have a 50 amp spa GFCI panel that I want to hook up to a 10-50P outlet and my controller will not require any 120V. The ground from the heating element / kettle will be connected to the controller then to the gfci panel then to the outlet.

That looks sketchy to me and I would be worried that the outlet you pigtail the ground to only has a small piece of copper to potentially take a short circuit of over 50 amps. That's just a gut reaction though.

The GFCI is an interesting thought though! I know that with 120v outlets that aren't grounded (like found in older houses,) it's acceptable to install a GFCI breaker to protect people against electric shock. I'm not sure if that's allowable with 240v but could be cheaper than a rewire and offer similar protection. Again, a qualified electrician would know for sure.

[quadra]

Thanks two sheds, threads like this are why electricians walk away when these conversations s start. I agree the ground lead on that adapter looks impossibly small and would probably not be correctly grounded by most users.
Ben, theNEC specifically prohibits using domestic plumbing pipes as a ground path, and creating additional or seperate Ground paths can create ground loops and shock risks and should only be done by a qualified electrician.
Bcook, can you please verify the breaker and wire size on the circuit... it is old enough to possibly have been installed as a 30A circuit so you want to ensure your wire is up to the task. The way you have the element wired now with two legs sharing a common neutral is also known as an Edison circuit - Google that to see why they are bad news.
In theory you can convert that circuit and outlet to a modern 240 and ground, but it would require an electrician and new plugs and receptacles etc.
It is common practice for electricians to use colored tape at both ends of a cord to reassign conductors, and although white is neutral in your setup green is always earth, getting a roll of red tape and marking off all the ends of those green conductor hot legs would be a good idea.

[cob]

So if you've seen my other thread on my controller build, you know it's not going as well as I thought it would. So I figured I'd ask the masses. How would you build a 9kw controller?

Large junction box
Digital ammeter/volt meter
Auber DSPR1 controller
80a SSR and heatsink
240v electromagnetic relay
30a double pole switch

Sorry for an additional topic about the same issue, but I need a fresh start.

You have spent 8 months on 2 threads messing with this. It is time for you to

take a step back and find a build that has already been done and proven and

start from scratch. If what you have in inventory fits in a build that is proven

that's a bonus. But you truly need to start from scratch with a proven build.

[bcook608]

Yeah, I'm done with this.

My panel is directly underneath the outlet I'm using so maybe down the road I'll update it to a 4-prong outlet and install a GFCI breaker.

There's an electrician that lives down the road from me. Maybe I'll buy him a beer (or a whiskey ) and see what he has to say.

Thanks for the help, everyone. It's clear to me that 240v is still beyond my reach at this time.

[Yummyrum]

It sounds like you are really close as far as having a functional Controller , it’s now just come down to a safety issue of not having an available ground that is holding you back .

Even if you went out and bought a fully functional controller , you can’t safely connect it .

Glad to hear you are going to wait until you have a 4 pin setup before you continue .

What has come out of this topic is a fuller understanding of the various power sources available and one step further in keeping us all safe .

[bcook608]

It sounds like you are really close as far as having a functional Controller , it’s now just come down to a safety issue of not having an available ground that is holding you back .

Even if you went out and bought a fully functional controller , you can’t safely connect it .

Glad to hear you are going to wait until you have a 4 pin setup before you continue .

What has come out of this topic is a fuller understanding of the various power sources available and one step further in keeping us all safe .

Well, I'm glad I can at least contribute in that manner.

[bcook608]

So when I rebuild this controller with a 4-wire setup and a 50A GFCI breaker, I can terminate the neutral in the box and then run a ground buss inside the panel that will connect all accessories and the element so that if there's an issue with it, it's fully protected. Correct?

[bcook608]

So if you've seen my other thread on my controller build, you know it's not going as well as I thought it would. So I figured I'd ask the masses. How would you build a 9kw controller?

Large junction box
Digital ammeter/volt meter
Auber DSPR1 controller
80a SSR and heatsink
240v electromagnetic relay
30a double pole switch

Sorry for an additional topic about the same issue, but I need a fresh start.

You have spent 8 months on 2 threads messing with this. It is time for you to

take a step back and find a build that has already been done and proven and

start from scratch. If what you have in inventory fits in a build that is proven

that's a bonus. But you truly need to start from scratch with a proven build.

The other thread was originally for my fist 120v controller. I've only been working on this one for a couple of weeks. I got all the components together then had to set it on the shelf for a while and didn't look at it for a while due to life events

[Yummyrum]

So when I rebuild this controller with a 4-wire setup and a 50A GFCI breaker, I can terminate the neutral in the box and then run a ground buss inside the panel that will connect all accessories and the element so that if there's an issue with it, it's fully protected. Correct?

Yes .

[bcook608]

So when I rebuild this controller with a 4-wire setup and a 50A GFCI breaker, I can terminate the neutral in the box and then run a ground buss inside the panel that will connect all accessories and the element so that if there's an issue with it, it's fully protected. Correct?

Yes .

Sounds good. Guess I'll get working on making friends with the sparky down the way

[Yummyrum]

When you rewire the controller , do use suitably sized cables as has been recommended by several members .

For example bring the input wires direct to the contactor rather than splicing and jumpering . Use the contactor terminals as connection points to feed other devices such as the DSPR1 , Fan , Voltmeter etc .

To be honest , I don’t really know why you even need a Power meter . You should be able to calculate power from the % on the DRPR1 . Also as (I think it was Salt MF said) at lower % settings , the readings are likely to jump around due to the pulsing of power.

[bcook608]

When you rewire the controller , do use suitably sized cables as has been recommended by several members .

For example bring the input wires direct to the contactor rather than splicing and jumpering . Use the contactor terminals as connection points to feed other devices such as the DSPR1 , Fan , Voltmeter etc .

To be honest , I don’t really know why you even need a Power meter . You should be able to calculate power from the % on the DRPR1 . Also as (I think it was Salt MF said) at lower % settings , the readings are likely to jump around due to the pulsing of power.

Yeah, that's going to be the plan. I just need to find appropriate connectors that will allow me to run 6ga wire to the smaller terminals inside the controller. That was the main reason for the solid 10ga wire, it was easier to make the connections and (in theory) should have been enough to handle the power. When I build the new one, I will try to source better connectors and do it right.

As for the meter, I'm going to take that advice and just have the switch, DSPR1, and a couple of cooling fans.

[zach]

[
The third wire is a neutral. It acts similar to a ground in a short-circuit situation in that it will allow a ton of current through therefore tripping the breaker, but it has to be wired to the right pieces of metal to protect someone which a neutral typically isn't.

I have the same 240 V receptacle on a dedicated 50 amp breaker for a 1999 vintage oven in a building permitted in 1998.

I am building a control panel and want to use this outlet. I have no need for a neutral wire in my portable GFCI breaker panel, my control panel, or heating element . All I want is two hots and a safe grounding path. I live in a rental .

My understanding is that GFCI functions without a neutral. The unit I have will trip with 5 mA difference in current between the two hot wires. The GFCI is my primary safety device to protect me in a potentially wet environment.

I believe that exception below in the current code ( NEC 250.140 ) the allows the 3rd wire or "grounded circuit conductor" from the outlet to be used as a ground with the following conditions for existing outlets only.

NEC 2020 (2023 has the same section)

250.140 Frames of Ranges and Clothes Dryers

Frames of electric ranges, wall-mounted ovens, counter mounted
cooking units, clothes dryers, and outlet or junction
boxes that are part of the circuit for these appliances shall
be grounded in the manner specified by 250.134 or 250.138.

Exception: For existing branch circuit installations only
where an equipment grounding conductor is not present in
the outlet or junction box, the frames of electric ranges,
wall-mounted ovens, counter-mounted cooking units, clothes
dryers, and outlet or junction boxes that are part of the
circuit for these appliances shall be permitted to be grounded
to the grounded circuit conductor if all the following conditions
are met.

(1) The supply circuit is 120/240-volt, single-phase, 3-wire;
or 208Y/120-volt derived from a 3-phase, 4-wire, wye connected
system.

(2) The grounded conductor is not smaller than 10 AWG
copper or 8 AWG aluminum.

(3) The grounded conductor is insulated, or the grounded
conductor is uninsulated and part of a Type SE service entrance
cable and the branch circuit originates at the service equipment.

(4) Grounding contacts of receptacles furnished as part of
the equipment are bonded to the equipment.


I plan of verifying where the 3rd wire or " grounded circuit conductor" lands in my main panel, the wire size, and if it is insulated, and that neutral and ground bars are bonded together with a sufficient wire size before I proceed.

[quadra]

A 240v GFCI breaker has three lugs 2 hot and a neutral, it also has a white pigtail that bonds it to the neutral bus. It is typically used with a 4 wire spa circuit that includes a ground.

[bcook608]

Any useful tips on how you'd connect 6ga wire to this element?

I was thinking about bolting this to each connection, then bending it to 90 degrees to screw in the wire:
https://megadepot.com/product/morris-pr ... GuHjbYwvds

[shadylane]

I'd bend the connecter first, stick the wire in and tighten it, then bolt it to the heater.
That way you're less likely to bugger up the heater.

[zach]

A 240v GFCI breaker has three lugs 2 hot and a neutral, it also has a white pigtail that bonds it to the neutral bus. It is typically used with a 4 wire spa circuit that includes a ground.

Not all GFCI breaker have four connectors.

https://www.gfcistore.com/30-amp-inline-gfcis.html


If no neutral is used on an appliance there is no need to connect the neutral on the GFCI panels that have a neutral connection. The voltage supplied to the control circuit in the GFCI breaker is induced from the hot wires. The spa panel will function with two hots and a ground. A leak of 5 mA to ground will cause a trip on a GFCI .

[NZChris]

You don't have to control the voltage to the whole 9kW.

That element has three 3kW elements, the links can be removed to isolate them.

You can switch two of them on and off, on separate circuits if necessary, and control the voltage to the third, so that your controller only has to be robust enough to control one 3KW element.

[quadra]

You bet, and that is still way better than just bonding your neutral and ground at the appliance with a regular breaker, but if you are going to the trouble why would you not add the earth ground?

[bcook608]

I'd bend the connecter first, stick the wire in and tighten it, then bolt it to the heater.
That way you're less likely to bugger up the heater.

And if things get too crowded, I can screw the ground into the outside of the housing to make sure nothing will get overheated and/or rub against one another.

[TwoSheds]

Any useful tips on how you'd connect 6ga wire to this element?
71BFikBWyFL._AC_SX425_.jpg



I was thinking about bolting this to each connection, then bending it to 90 degrees to screw in the wire:
https://megadepot.com/product/morris-pr ... GuHjbYwvds

I don't know why ring terminal connectors wouldn't work as long as they're appropriately sized:

https://www.homedepot.com/p/Gardner-Ben ... /202521494

Also probably bend carefully to a 90 for easier hookup. It gets tight inside those covers.

NZChris makes a good point that you could separate the elements rather than controlling them together. That would allow you to use lighter gauge wire but you'd have to have more conductors. It would give you finer control though. 9kw at 1% increments is 90w per step. 3kw would be 30w per step.

Worth considering.

[Windy City]

Any useful tips on how you'd connect 6ga wire to this element?
71BFikBWyFL._AC_SX425_.jpg



I was thinking about bolting this to each connection, then bending it to 90 degrees to screw in the wire:
https://megadepot.com/product/morris-pr ... GuHjbYwvds

These will be much easier to bend and make fit
You only need two. One for each side
https://windynationstore.com/products/6 ... LbEALw_wcB

[shadylane]

You don't have to control the voltage to the whole 9kW.

That element has three 3kW elements, the links can be removed to isolate them.

You can switch two of them on and off, on separate circuits if necessary, and control the voltage to the third, so that your controller only has to be robust enough to control one 3KW element.

That's what I was thinking also.