3 Phase Wiring Review

[Pleiades]

I'm moving into a building with 240v 3 phase, and will be setting up a 1 to 2 BBL system. I'm looking to modify my existing 240v control panel, built according to the Electric Brewery instructions, to power 3 phase elements in the boil and hot liquor kettles. I currently have a single 240v 5500 watt Camco element in each kettle, and plan to use something similar to this BrewPi element. I'm thinking the relays/contactors for power in and the two kettle outputs, as well as the two SSRs can all be replaced with suitable 3 phase items, and then run the control and pumps from a single live leg of the three phase relay. I'll dispense with the volt and ammeter, and pretty much everything else should be fine as original

I'll need a sparkie to come through to wire up the connections, and will run him through my set up to ensure I have crossed my i's and dotted my t's on things such as current draw, GFCI, etc

Here are a couple of drawings that show what I'm trying to modify, would appreciate any input.

Everything else will be wired as per The Electric Brewery, with the appropriate modifications for Australian 240v. Earth wiring will be in place, just not shown here

Power Supply and Switch

Element Wiring

 

[mredge73]

I have never worked with 3 phase 240vac.
But I have lots of experience with 3 phase 208vac as it is a common industrial transformer in the USA.
Any leg to neutral is 120vac, leg to leg voltage is 208vac. The transformer is balanced and doesn't have a "wild leg".

Maybe you have one of these weird open delta transformers, is this what your power in looks like:
http://www.oempanels.com/wp-content/uploads/2017/02/240V-3-Phase-Open-Delta-300x191.png

 

[Pleiades]

Any leg to neutral is 120vac, leg to leg voltage is 208vac. The transformer is balanced and doesn't have a "wild leg".

Australia is run on 230v, +10%/-6%, so three phase "leg to leg" is 400v. The elements I'm looking at are technically not three phase, they will be wired in a wye (or star) configuration, (see image below), which will equate to 3 x 230v elements. I'm basically taking advantage of 3 phase offering me 3 x 230v circuits in one.

You raise a good point on the neutral - I'm not sure if the kitchen is wired with a neutral, as I've not yet signed the contract and have no access. But, I'll be putting in a new circuit, because I can't brew in a commercial kitchen

Maybe you have one of these weird open delta transformers, is this what your power in looks like:
http://www.oempanels.com/wp-content/uploads/2017/02/240V-3-Phase-Open-Delta-300x191.png

Again, with no access for at least a month, I'm not sure. I do have three phase in the shed at home as well, I really should take a look to familiarise myself

3 Phase Element - the linked poles are neutral, the other three for L1, L2, L3

 

[mredge73]

Cool, thanks for explaining.
The transformer feeding your house will be balanced and you do have it wired correctly in your diagram above.
The element pictured is configured for a "Y" power input so it is fully capable with your system. Connect it 3 phase without a neutral, just make sure it is a 3 phase 400vac.
This will give you your maximum efficiency.
See the image to the right: