Two 80 amp 3-pole breakers instead of a (1) 160 amp 3-pole breaker

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ramsy said:
Can total load be discounted by dividing it by 1.732 if not feeding 3-Phase loads? 2-pole breakers feed single-phase loads.
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Maybe I missed something but if you have a load of 100 amps (my hypothetical number and nothing to do with your equipment) on all three phases then that is the load on each conductor.

If instead you had a rating of 36 kVA and divided it evenly across three phases then that would still be ~100 amps but if it were 36 kVA across only two leads it jumps to 173 amps.

That 1.73 factor only applies when you are figuring the current of balanced three phase circuit when power is what is known.
 
Todd0x1 said:
There is no way that PDU is going to receive a UL (or other NRTL) listing. What is the 'certification' it is undergoing?

Also, I am 98.5% sure you cant have a hardwired pdu with IEC receptacles. My logic is that if its hardwired then its part of the structure and is permanently installed. Cant permanently install IEC receptacles due to their use on multiple voltages. Someone please correct me if I am wrong here.
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This probably explains why you cannot find a "duplex" type IEC receptacle. Not sure about certification. There is a popular Crypto Beast PDU that is NRTL listed and the first line of the description is "The product covered by this report is a permanently connected, Class I, power distribution unit intended for fixing onto a shelf". It also comes with lugs for wiring.
 
kwired said:
Maybe I missed something but if you have a load of 100 amps (my hypothetical number and nothing to do with your equipment) on all three phases then that is the load on each conductor.

If instead you had a rating of 36 kVA and divided it evenly across three phases then that would still be ~100 amps but if it were 36 kVA across only two leads it jumps to 173 amps.

That 1.73 factor only applies when you are figuring the current of balanced three phase circuit when power is what is known.
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183 amps of single-phase load. 3-phase is brought to the unit and then single-phase is broken out. So you get 105.7 amps on three-phase (100 amp breaker 3-phase is derated to 80 amps)..
 
cottora said:
This probably explains why you cannot find a "duplex" type IEC receptacle. Not sure about certification. There is a popular Crypto Beast PDU that is NRTL listed and the first line of the description is "The product covered by this report is a permanently connected, Class I, power distribution unit intended for fixing onto a shelf". It also comes with lugs for wiring.
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I am likely out of my league here but the standard its listed to is 62368 which seems like an end run around getting the pdu listed for what it really is (which I don't think it could be)
 
I'm not understanding the entire discussion.

You mention that the 400 amp square D Panel can give you 100A-3Pole outputs. Why not just install (2) 100A-3Pole breakers and the associated (2) IEC 60309 pin & sleeve plugs (100A plugs) and then plug in these 100A PDU's that seem to be similar to what you want. They are already listed. https://www.raritan.com/product-sele...l/px3-4213u-v2
or this one https://www.raritan.com/product-sele...l/px2-5941v-v2
or this one https://www.raritan.com/product-sele...etail/px2-4941
 
ron said:
I'm not understanding the entire discussion.

You mention that the 400 amp square D Panel can give you 100A-3Pole outputs. Why not just install (2) 100A-3Pole breakers and the associated (2) IEC 60309 pin & sleeve plugs (100A plugs) and then plug in these 100A PDU's that seem to be similar to what you want. They are already listed. https://www.raritan.com/product-sele...l/px3-4213u-v2
or this one https://www.raritan.com/product-sele...l/px2-5941v-v2
or this one https://www.raritan.com/product-sele...etail/px2-4941
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Because they cost money. He's already said that.

-Hal
 
At least those look to have the correct OCPD just ahead of the receptacle outlets (20 amp) where the one's in the OP"s post do not.

JAP>
 
This same manufacturer has a 3 x 40 amp model. We may just hardwire three single-phase 40 amp lines directly into the internal breakers. This looks to be the safest route as the actual internal breakers are UL listed.
 
cottora said:
183 amps of single-phase load. 3-phase is brought to the unit and then single-phase is broken out. So you get 105.7 amps on three-phase (100 amp breaker 3-phase is derated to 80 amps)..
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Given the load of 21960 Watts from 183 amps x 120 volts:

105.6 amps appears in my spreadsheet when (1º,3w) transformer is selected without changing 208v LL back to 240v LL.

61 amps @ 208v LL appears when (3º, 4w, Wye) transformer is selected, or 76.2 amps for continuous loading.

We have some engineers on this forum that might help check these figures.
 
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jap said:
I'm still trying to figure out where the individual protection is for the individual 120v outlets.



JAP>
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There are 120v outlets? The drawings look like the outlets are 208v single-phase. I did notice the drawing didn't show a neutral but that picture of the 5-wire connection looks like the neutral is being used but I couldn't tell to what.
 
hbiss said:
Because they cost money. He's already said that.

-Hal
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I guess I missed that.
What I did see in post #5 was “But we then void certifications. Fundamentally there is no issue with that, but the insurance man will probably disagree.”
so shoemaker-ing a bunch of individual components together doesn’t make an overall listed appliance.
The insurance man won’t like that. Just buy something that will not burn the place down.
 
cottora said:
183 amps of single-phase load. 3-phase is brought to the unit and then single-phase is broken out. So you get 105.7 amps on three-phase (100 amp breaker 3-phase is derated to 80 amps)..
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correct on the 105.7 A if the loads are @ 208 volts. If they are 120 volt loads then divide by three (presuming you can split it evenly) as you will have one third of the load on each ungrounded conductor.

If you have 105.7 amps and it is continuous load you need 1.25 x 105.7 = 132.125 amps minimum conductor size as well as overcurrent protection. The overcurrent protection can be next standard size up which is 150 amps.
 
ron said:
I guess I missed that.
What I did see in post #5 was “But we then void certifications. Fundamentally there is no issue with that, but the insurance man will probably disagree.”
so shoemaker-ing a bunch of individual components together doesn’t make an overall listed appliance.
The insurance man won’t like that. Just buy something that will not burn the place down.
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Buying "Google" data center quality equipment will cost more than if the place burned down...One 3PH switched 30AMP ADP PDU is $1,000. This would have about $900 worth of equipment attached.

I do understand the mentality of "doing things right". Yet, a lot of data center equipment has been engineered to suit the needs of 99.99% uptime and where downtime is extremely expensive. We are the opposite, I'll take a few % downtime to save money as I am not penalized beyond the actual work time for being down (a major data center would lose business for being down just 1%).
 
One thing to keep firmly in mind is that, at least for Bitcoin, the "mining" process has reached a point where the expected returns for a given block of computation is very low. A small increment in initial system cost could actually keep the operation from being profitable at all.

Sent from my XT1585 using Tapatalk
 
cottora said:
The three-phase wiring input is broken out into (3) single phase 63 AMP banks (100% rated).
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There is no way that your 63A breaker is 100% rated. when it is mounted in an enclosure like you have.

For decades, I have applied a lot of breakers dual rated for both IEC and NEC installations. Not once have I considered or treated their full load current ratings differently
 
GoldDigger said:
One thing to keep firmly in mind is that, at least for Bitcoin, the "mining" process has reached a point where the expected returns for a given block of computation is very low. A small increment in initial system cost could actually keep the operation from being profitable at all.
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You know Bitcoins better than I do, but my feeling is that this is just a big waste of time by people who think they are going to strike it rich.

Then I'm just waiting for the government to crack down on it because it facilitates the exchange of untraceable funds to support illegal activities.

Now back to your regular programming...

-Hal
 
hbiss said:
You know Bitcoins better than I do, but my feeling is that this is just a big waste of time by people who think they are going to strike it rich.

Then I'm just waiting for the government to crack down on it because it facilitates the exchange of untraceable funds to support illegal activities.

Now back to your regular programming...

-Hal
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It is basically like Gold. No real value (unless you are a rapper shooting a music video) and expensive to create. But there are a few things that make it better 1) you can transact much easier 2) it is one of the few platforms that is highly secure from hacking 3) anonymous store of value

Keeping with the Gold analogy GoldDigger is correct, margins have become tight so the only winners are those that can mine with the least cost. Just like gold mining...
 
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