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575VAC, 3-Ø 24VDC power supply

Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
For a variety of reasons I would like to convert our designs to use direct supply 3-Ø input power supplies for our 24VDC control power. The issue I'm running into is that few (none that I can find so far) support 600VAC - Think Canadian industrial power. Does anybody know of a power supply that is rated for this high of a nominal voltage input? I notice that some claim an input range as high as 575, but the rated nominal voltage is only 500V.

Part of my concern is designing around a supply voltage of 575 nominal where a component is rated for a MAXIMUM input voltage of 575. It seems to leave no margian for input fluctuations, which are not very uncommon - especially in environments full of high power switching.

Thank you for your input.
 

synchro

Senior Member
Location
Chicago, IL
Occupation
EE
Do you have 346V L-N available? If so, maybe there are single-phase 24VDC power supplies that would work off of that voltage. Or an autotransformer might be used to drop from 600V to 480V.
 

Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
I wasn't talking about a specific scenario, I was talking about in general. We do a ton of jobs with varying requirements for control power and with different supply schemes. What I prefer to target is the common options. If I can design a popular system so it can be used for 480VAC in the US as well as 600VAC in Canada, I can do the design once, and configure it based on final destination. I would prefer not to put in one power supply for one customer that has 346, and a different design for someone on 480 and another for a site with 575 and another that supports 277. As it is, I can use a power supply with 120VAC input/24VDC output & throw a control transformer on it that supports the supply voltages mentioned by just configuring the taps.

For example, the Siemens Sitop 8200 line would give me a 20A and a 40A option that would cover almost everything I need, but they don't rate for 600VAC nominal.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Virtually everyone Eaton offers them for sure, and Eaton are brand labeled from Delta, so you can find them there too, but stop looking for “575V”, they will be called 600V.

There are a few brands that sell a 550V version and their input tolerance will handle 600V at the peak, but it leaves little margin of error.

I modified my earlier post, I thought Siemens and Puls had them, but no. 500V max.
 
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Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
Virtually everyone offers them, ...
Can you provide a specific model number, or a link? I'm looking & only find them rated to 500V. The difficulty is finding one rated above 500V. Some list 575V as a maximum input voltage, but certainly nobody is claiming 600V input for a 24VDC output power supply. None that I'm finding, anyway.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Can you provide a specific model number, or a link? I'm looking & only find them rated to 500V. The difficulty is finding one rated above 500V. Some list 575V as a maximum input voltage, but certainly nobody is claiming 600V input for a 24VDC output power supply. None that I'm finding, anyway.
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Hmmm the data sheet says "Nominal Input Voltage 3 x 400-500 Vac"
But it also says it works on '2-phase' LOL.
I wonder about the accuracy of this data sheet?
I would expect it to be tested to ANSI C84 voltage range of 540- 630V for 600V 'nominal system voltage' or '575V nominal utilization voltage'

1709833715428.png
 
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Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
Well, I can go home for the day, having learned something new. I wish the specifications were a little less ambiguous. They rate these things for (in the Delta example) 400-500V nominal, and allow a range of 320-600V. The note says 600 is the maximum. Obviously, if you're working 600V (or 575V) as your nominal value, that makes your max voltage 604-630V... outside their input range. I hate to make assumptions, but I guess I would have to assume the range includes additional margin to accept the ANSI range of fluctuations.

Edit: I meant to also say "Thank you."
 

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
When I am writing specifications for something like a power supply for use in North America I put "input voltage range to meet or exceed" and include a reference to ANSI C84 Table 1 Voltage range B (if the voltage is in there notice its missing 4 wire 600Y/347 ) :
1709838755324.png
 

Todd0x1

Senior Member
Location
CA
Not sure if this helps but Meanwell WDR-480-24 gives you 20 amps of 24v with an input range of 180-550vac, there are lower wattage models in the same series as well.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Hmmm the data sheet says "Nominal Input Voltage 3 x 400-500 Vac"
But it also says it works on '2-phase' LOL.
I wonder about the accuracy of this data sheet?
I would expect it to be tested to ANSI C84 voltage range of 540- 630V for 600V 'nominal system voltage' or '575V nominal utilization voltage'

View attachment 2570446
Outside of North America, what we would call “single phase”, meaning 2-out-of-3 phases, is called “2-phase”. We don’t do that here, because we have true 2 phase power.

IMG_0815.jpeg
 

Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
FWIW - I received confirmation last night from the Siemens SME that a 600VAC to 24VDC power supply supporting the Canadian market is no longer offered. He cited a lower than expected demand, leading to discontinuation. :( He further confirmed the 8200 series, which has a data sheet reflecting 575V as being within its input rating, is not suitable for use on Canadian 600V supply. His recommendation was for use of a step-down transformer or to use L-N ('2 phase') 332VAC.
 

kwired

Electron manager
Location
NE Nebraska
Occupation
EC
For a variety of reasons I would like to convert our designs to use direct supply 3-Ø input power supplies for our 24VDC control power. The issue I'm running into is that few (none that I can find so far) support 600VAC - Think Canadian industrial power. Does anybody know of a power supply that is rated for this high of a nominal voltage input? I notice that some claim an input range as high as 575, but the rated nominal voltage is only 500V.

Part of my concern is designing around a supply voltage of 575 nominal where a component is rated for a MAXIMUM input voltage of 575. It seems to leave no margian for input fluctuations, which are not very uncommon - especially in environments full of high power switching.

Thank you for your input.
Are you wanting "three phase" input or just two lines from a three phase system? I'm assuming if it is supplying control power it is rather limited VA capability.
 

Tip DS

I'm here.
Location
The Great Meme State
Occupation
Electrical Engineer
OK, it's pretty much official... I've heard from all the major and a few of the minor players in the market. Nobody currently offers a power supply that supports direct conversion from Canadian industrial 600VAC, 3-Ø to 24VDC. I have had offers to have them manufactured, but it just doesn't make good financial sense for a few panels per year that might use them. To that point, even when pricing the lesser (600VAC max) power supplies, their cost to go directly from 500VAC to 24VDC is almost triple the cost to use a control transformer ahead of a 'regular' 24VDC power supply. I think I'm going to put this effort to rest, but I wanted to document the results here. Thanks to all for your input.
 

GeorgeB

ElectroHydraulics engineer (retired)
Location
Greenville SC
Occupation
Retired
It used to be common to see 400-3-50 systems use that as a 24VDC supply, usually Siemens SITOP. They were typically rated for 400-500, but we had some trouble with them on 480-3-60 systems.

Our friends at AutomationDirect offer many for 480-3-60; I've no experience in the last 15 or 20 years.
 
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