230 VAC, 2Ph, IT System (Neutral configuration) vs non-UPS supply at 230 VAC, 1Ph, 50Hz

[itsmetinnie]

Please help to explain the difference between these 2 supplies:

- supplied from UPS supply at 230 VAC, 2Ph, IT System (Neutral configuration
type) 50Hz, by a dedicated redundant power cables;

- supplied from non-UPS supply at 230 VAC, 1Ph, 50Hz

We are buying a PLC Siemens SR30 model and our vendor says that their PLC is compatible with 220V, 1 Phase and not to 230VAC 2 phase. What is the difference please, Supply from our side is 230 VAC, 2Ph, IT System (Neutral configuration
type) 50Hz, by a dedicated redundant power cables;

 

[Heaviside1925]

OP,
Hopefully this answers your question.
Link

I am assuming it something like this. Link

I would send a tech sheet for the UPS to Semien PLC engineering support and ask them. I am guessing the vendor may not be familiar with this type of UPS.

 

[waross]

230VAC 2 phase

Generally, 2 phase has been obsolete for over 50 years.
There may be some niche systems still in operation.
"Two phases of a three phase system" is "two phases of a three phase system" not two phase.
However, some newbies continue to misuse the term "phase".
There was a tendency of some on this forum to describe a single phase, center-tapped system as two phase.
Wrong. Historically, two phase implies a phase shift, not a center tap.
Still wanting to misuse the word "phase" some started to call a "Single phase, center-tapped" system a "split phase system".
Wrong. "Split phase" describes a starting scheme used to start some single phase motors.

If you are going to claim a 180 degree phase shift rather than revered polarity, I will demand that you accept a two 12 Volt batteries in series to supply both 12 Volt and 24 Volt loads as a two phase DC system.
If you claim that reversing connections creates a phase shift, I will demand that you accept a reversing switch on a simple permanent magnet DC motor as a two phase system.

Despite the information in the manufacturers link provided by Heaviside1925 (Mechanical), I very much doubt that that so called two phase UPS would function on a true two phase system.
Try it on a true two phase system and then try to get warranty.

(1) Hard Wire 3-wire (2PH + G) (Battery Backup) Should be:
(1) Hard Wire 3-wire (H + N/G + H) (Battery Backup)
(1) Hard wire 3-wire (H N + E) (Battery Backup)
(1) Hard Wire 3-wire (H N + G) (Battery Backup)

SINGLE PHASE, CENTER TAPPED. not Two Phase.


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Heaviside1925]

OP,
I agree with all of waross' points. I was not trying to indicate that this was truly a 2-phase system. When I hear the word vendor, I hear salesperson with some technical knowledge. I do not think your PLC vendor is familiar with the wording described in the UPS specifications and any confirmation you require would likely need to come from Siemens engineering, since it is likely out of scope of your vendor's technical knowledge. Alternatively, you could ask the PLC vendor to talk to the UPS vendor because I suspect as well, what the UPS vendor is calling two phase is actually single phase, center tapped.

 

[waross]

European one of three phases; 230/400 Volts. L1-N - 230 Volts
North American single phase; 120/240 Volts. L1-N = 120 Volts, L1-L2 = 240 Volts (No neutral/ground connection on the power circuit.)
North American thee phase; 120/208 Volts. Phase to neutral = 120 Volts. Phase to phase = 208 Volts. (No neutral/ground connection on the power circuit.)

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[waross]

I hear salesperson with some technical knowledge.

There are some very knowledgeable sales persons, however that phrase is often an oxymoron.


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Heaviside1925]

waross, I couldn't agree more. I thought I'd be nice and split the middle by saying "some". Reminds me of "Fraser's Rule" Warranty and guarantee clauses are voided by payment of the invoice.