list of psu's that will run on 277

[jstew]

S4 psu WILL run fine on 277.  Not over 300V.  It does require a slight modification.

care to share?

[1714861884]

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[1714861884]

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[1714861884]

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[1714861884]

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[Finksy]

277V requires half the breaker slots that 240V does.  (If single pole = half double pole)

Out of curiousity, is that because 277V is taking 1 leg of 3-phase power as opposed to 2x "halves" of split phase power to make 240V?  And if so, is balancing the 3 legs of 3-phase crucial when dealing with single power sources (like PSU's)?

[jstew]

277V requires half the breaker slots that 240V does.  (If single pole = half double pole)

Out of curiousity, is that because 277V is taking 1 leg of 3-phase power as opposed to 2x "halves" of split phase power to make 240V?  And if so, is balancing the 3 legs of 3-phase crucial when dealing with single power sources (like PSU's)?

yeah since ur only pulling form 1 leg u only need a single pole breaker , its not critical to balance the load between all 3 phases on my setup is what the electricall guy told me but my breaker panel rotates which pole leg each single pole breaker hooks into as u install them into the panel.
like this

breaker 1 - leg 1
breaker 2 - leg 2
breaker 3 - leg 3
breaker 4 - leg 1
breaker 5 - leg 2
breaker 6 - leg 3
breaker 7  leg 1
etc etc

we just ran all the main wires today and should be hooking them up to power in a lil while after lunch ill take pictures when its done today , the only think im missing is my plugs and outlets , i may try to wire up a single 110 outlet to the 277 just so i can plug in a single psu and see how it does , if not i have to wait till friday or monday for that stuff to be delivered to wire up all the lines

i might have some 240v stuff laying around that would be safer to use vs the 110 outlet for testing the setup today

[Finksy]

Cool.  So when you are powering a PSU or PDU for example, do you have to use a hot, a neutral as well as a ground, instead of the 2x hots + ground that you would see in a typical 240V application of single phase? Or else what do you use on the plug/receptacle where the 2nd hot would typically go?

[jstew]

Cool.  So when you are powering a PSU or PDU for example, do you have to use a hot, a neutral as well as a ground, instead of the 2x hots + ground that you would see in a typical 240V application of single phase? Or else what do you use on the plug/receptacle where the 2nd hot would typically go?

hot neutral and ground , same way u would wire up a normal 110v outlet

[altcointalk14]

You must make sure your neutral and ground are separated.  install another ground rod at your breaker panel.

Also, you will want to try to balance the load, it will improve your power factor and reduce the amps on your neutral going back to power ground.

If you want to know how to modify the S4 PSU, pm me.  I dont want a debate on here.

[jstew]

bringing this thread back does anyone know for sure if an sp31 will or will not run on 277 depending on the psu

i just picked up some sp31's and i put them on my 240 for now but would like to move them over to 277v power if possible , they have artyserian psu's in the or however the hell u spell it

[scyth3]

bringing this thread back does anyone know for sure if an sp31 will or will not run on 277 depending on the psu

i just picked up some sp31's and i put them on my 240 for now but would like to move them over to 277v power if possible , they have artyserian psu's in the or however the hell u spell it

The PSU from the SP10 is the same or similar to the PSUs in the SP31.

[NotFuzzyWarm]

You must make sure your neutral and ground are separated.  install another ground rod at your breaker panel.
<snip>

That violates every countries National Electric Codes. For power wiring a neutral must ALWAYS be tied to a ground at the incoming power panel. That is what makes it a Neutral vs just another Hot wire...

Technically, the major distinction between Neutral and Ground wires is that Neutrals are for carrying current whereas Ground is strictly a safety wire.

What you described is commonly referred to as 'isolated power' and is restricted for use only with very sensitive test equipment. A variant of it is an isolated ground setup (usually orange power sockets) that is much like you described except the neutral is still tied to ground but with care that the Neutral/Ground bonding only happens at 1 location.

As to single phase PSU incoming power connections -- Makes no difference if L1 or L2 are Hot and the other is Neutral.

[altcointalk14]

You must make sure your neutral and ground are separated.  install another ground rod at your breaker panel.
<snip>

  the neutral is still tied to ground but with care that the Neutral/Ground bonding only happens at 1 location.

That is correct.  tie your neutral to ground at incoming power location.
A new ground could be helpful at a downstream subpanel.  keep the ground and neutral seperate at subpanel.

[jstew]

just edited the list to move dps-2000bb from working , to working but unreliable
, i have gone threw aot of dps-2000bb in my dc on 277v power i only get about 1-2 months out of them so i dont suggest using them with 277v
i have ibm 2880's that are 2 years old still going strong on 277

[NotFuzzyWarm]

just edited the list to move dps-2000bb from working , to working but unreliable
, i have gone threw aot of dps-2000bb in my dc on 277v power i only get about 1-2 months out of them so i dont suggest using them with 277v
i have ibm 2880's that are 2 years old still going strong on 277

....
So -- why -- don't you just pick up a few buck/boost transformers with 32v secondaries and knock the 277v line down to more reasonable 245vac??? They are not expensive. A DPS 2kw supply would need one rated to handle 266VA, call it 300VA with margin.

[agentcash]

just edited the list to move dps-2000bb from working , to working but unreliable
, i have gone threw aot of dps-2000bb in my dc on 277v power i only get about 1-2 months out of them so i dont suggest using them with 277v
i have ibm 2880's that are 2 years old still going strong on 277

Do you have any reliability data on the Dell Z750P's on 277v?

[jstew]

just edited the list to move dps-2000bb from working , to working but unreliable
, i have gone threw aot of dps-2000bb in my dc on 277v power i only get about 1-2 months out of them so i dont suggest using them with 277v
i have ibm 2880's that are 2 years old still going strong on 277

Do you have any reliability data on the Dell Z750P's on 277v?

i have 4 of those i have been running on 277 for 1.5 years now they are reliable on 277

[jstew]

just edited the list to move dps-2000bb from working , to working but unreliable
, i have gone threw aot of dps-2000bb in my dc on 277v power i only get about 1-2 months out of them so i dont suggest using them with 277v
i have ibm 2880's that are 2 years old still going strong on 277

....
So -- why -- don't you just pick up a few buck/boost transformers with 32v secondaries and knock the 277v line down to more reasonable 245vac??? They are not expensive. A DPS 2kw supply would need one rated to handle 266VA, call it 300VA with margin.

because its just cheaper to run the reliable 2880's or other 277 reliable psus

[QuintLeo]

i dont belive u can get 480v power at most residential locations

 It's not standard, but if you're willing to pay the cost it CAN be done at many or most residences - most of the cost would probably be the installation of a 440v 3-phase transformer, but the wiring would add some too. Standard distribution in a neighborhood from the substation is normally 3-phase at 10kV ballpark.