Eaton managed PDU (208V) $120 NIB

WeekendWarrior

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Eaton's "managed" PDUs measure power through each outlet and allow an outlet-by-outlet ability to turn the power on/off. This set of features is Eaton's highest-end PDU.

Managed PDUs can be fairly pricey, especially when new. This listing is a crazy good deal for a brand new, Eaton managed PDU: Eaton ePDU - EMA 106-10 Vertical; Managed-G3; 21U In: 10 ft cord, C20 & L6-20P | eBay

I offered $120/each for 13, including shipping, and they accepted. I received them new in box. I believe that this price was available because Eaton recently scaled back the breadth of their PDU offerings and this model was EOL'd.

A couple things bear mention. First, this is a 208/240V unit with a L6-20P plug. Second, it has 7 outlets (sufficient for my needs but other units have more plugs).

This is an ideal PDU as one of several, mounted vertically, in a 28U rack.
 

klui

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Feb 3, 2019
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A couple things bear mention. First, this is a 208/240V unit with a L6-20P plug. Second, it has 7 outlets (sufficient for my needs but other units have more plugs).

This is an ideal PDU as one of several, mounted vertically, in a 28U rack.
The listing's label shows input is 100-240V, so it can work on 120V. Do your units show the same input rating? It's too bad the AP7864s that show up as suggested listings are 3PH because their prices are so much lower, albeit used.
 

cmmh

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Feb 26, 2021
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Darn. now I have to look into whether I can install a 240V plug in my server closet.

Edit:
Actually, the CAD drawing the listing says that it will work 100V-240V. Obviously you may need to modify the provided line cord for your power source.
 
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redeamon

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Yes 3 phase only. Definitely not going to happen in a home unless you do some crafty rewiring- don't do it.
 

T_Minus

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Yes 3 phase only. Definitely not going to happen in a home unless you do some crafty rewiring- don't do it.
You can get 3-phase at home from the power company, it doesn't require "crafty" re-wiring.
Some of us have phase converters which.. again.. isn't craft re-wiring.
I wouldn't run a phase converter to run this though ;) but to run shop equipment, well that's something different :cool:
You can also get 3-phase easily with solar nowadays too, I have it planned when I upgrade solar :D
 

redeamon

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If I'm not mistaken aren't the transformers on the poles 2 phase?

I doubt they're going to swap a transformer to give you 3 phase... and if you're going the phase converters route then you probably want it for full capacity (likely 50+ amps) which is going be pretty unreasonable in terms of efficiency, heat etc.

What I meant by crafty re-wiring was at the PDU level- since it has 3 breakers, it's 1 phase per breaker, so you might be able to run it with 2 phase, with 1 phase being dead resulting in one bank being dead. I don't recommend this though at all. The monitoring circuits would likely kill the entire thing anyway.
 

T_Minus

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If I'm not mistaken aren't the transformers on the poles 2 phase?

I doubt they're going to swap a transformer to give you 3 phase... and if you're going the phase converters route then you probably want it for full capacity (likely 50+ amps) which is going be pretty unreasonable in terms of efficiency, heat etc.

What I meant by crafty re-wiring was at the PDU level- since it has 3 breakers, it's 1 phase per breaker, so you might be able to run it with 2 phase, with 1 phase being dead resulting in one bank being dead. I don't recommend this though at all. The monitoring circuits would likely kill the entire thing anyway.
Well considering I have 3-phrase, a phase converter and have talked to the power company about upgrading again I like to think I know what I'm talking about... However, I'm sure this is unique to each location though, and depending on how far you are from the pole :D Where I'm at 3-phase or 400amp normal\single will run 15 to 25k$ for install. It's not a unicorn. It cost money. You get your own transformer either way ;) On solar it's simply another inverter and more wiring ~$3000 to add that 3rd-leg for systems capable of handling it. Much cheaper actually than from the grid power, but of course you're not getting 100amps additional either more like 30-40 usable for that price :)

I still wouldn't buy this though to save $ vs. a better option that worked power you had already though LOL
power upgrade is $$$
 
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Layla

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Since actual computer power supplies run on single phase, 3-phase is really only "good" for a few things for an end-user:
1. Saving on wiring - you can run more current through a smaller gauge wire / less copper.
2. Redundancy - if you lose just one phase you still have some operational circuits.

But 3-phase downsides vs. 240V single phase:
1. Lower PSU efficiency @208V combining two phases at 120 degree offsets vs. 240V
2. Harder to load balance your PDUs because you have to balance across phases
3. Losing one phase takes out multiple 208V circuits.

In other words, 3-phase adds complexity. If you're running a datacenter, the complexity might be worth it for the copper savings and because the power company might make you balance your use across 3 phases at such large loads (and you probably have 3-phase generators). For home use, unless your building already has 3-phase, or you also need to power things like motors, the complexity generally isn't something to seek out. :)

If you have cheap/cheaper access to three-phase it makes sense, but otherwise I'd generally just prefer lots of 240V. Eventually I'm guessing we'll see datacenters move to 416V/480V to further improve efficiency.
 
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fake-name

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If someone has one of these, can you comment on the resolution of the power measurement?

I have some avocent smart-PDUs, but they only measure in 0.1A increments, which mean it's only good to ~24/12W (240V/120V respectively).

This means they're not useful for things like small appliances (modems/switches/etc), since it basically doesn't register their power draw. I can totally see something that's going to be used for just checking power consumption at the rack level being fine with 0.1A resolution, but I like to track things much more finely that that.

If this goes to 1 mA (0.001A) I'll be all over getting one, even if I have to convert it to 240V single-phase (this wouldn't be the first PDU I've rewired).
 

unclerunkle

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If someone has one of these, can you comment on the resolution of the power measurement?

I have some avocent smart-PDUs, but they only measure in 0.1A increments, which mean it's only good to ~24/12W (240V/120V respectively).

This means they're not useful for things like small appliances (modems/switches/etc), since it basically doesn't register their power draw. I can totally see something that's going to be used for just checking power consumption at the rack level being fine with 0.1A resolution, but I like to track things much more finely that that.

If this goes to 1 mA (0.001A) I'll be all over getting one, even if I have to convert it to 240V single-phase (this wouldn't be the first PDU I've rewired).
I would be interested to know this as well
 
Jun 22, 2015
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I purchased these and I can confirm that the precision is 0.001A. The system uses 0.125A (on 120V) with no outlet used. Other good things about these:
It displays cumulative kWh value for each outlet.
You can daisy-chain several of these and then on one web page the information of all PDUs are displayed. It comes with splitters/cables to enable this if you want to daisy-chain more than 2.
You can reset to factory default easily with a LCD display and a few buttons.
Overall they are a big step up from the old AP7900s I have been using. One caveat though: if you have been using NEMA to C13 cables you will need to purchase a bunch of C14 to C13 cables to use with these.
 

NateS

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If I'm not mistaken aren't the transformers on the poles 2 phase?

I doubt they're going to swap a transformer to give you 3 phase... and if you're going the phase converters route then you probably want it for full capacity (likely 50+ amps) which is going be pretty unreasonable in terms of efficiency, heat etc.
That depends on a lot of factors actually. You're right that usually, at least in smaller neighborhoods, the pole transformers provide just the regular split two-phase, but the bigger ones could be three phase delta with center taps, and then they just distribute two of the three phases to each house (though note that'd likely be 240V three phase, not the more common 208V). Apartment complexes (and all of NYC) often get only 208V three phase, and distribute two of the three phases to each residence (which means no one has a true 240V).

It's also fairly common in more commercial-type installations to expect customers to provide their own transformers. In that case, they might drop you, say, 480V three phase (which is fairly standard commercial power in the US) and expect you to buy the appropriate gear to interface it with your equipment. But if you pay them enough, your electric company can probably supply whatever you want, but it may be much more expensive than something more standard. Sometimes it's cheaper to just get a phase converter.
 
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Layla

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That depends on a lot of factors actually. You're right that usually, at least in smaller neighborhoods, the pole transformers provide just the regular split two-phase, but the bigger ones could be three phase delta with center taps, and then they just distribute two of the three phases to each house (though note that'd likely be 240V three phase, not the more common 208V). Apartment complexes (and all of NYC) often get only 208V three phase, and distribute two of the three phases to each residence (which means no one has a true 240V).

It's also fairly common in more commercial-type installations to expect customers to provide their own transformers. In that case, they might drop you, say, 480V three phase (which is fairly standard commercial power in the US) and expect you to buy the appropriate gear to interface it with your equipment. But if you pay them enough, your electric company can probably supply whatever you want, but it may be much more expensive than something more standard. Sometimes it's cheaper to just get a phase converter.
I think you mean 120V three phase (not 208V three phase)? 208V is what you get when you combine the hot wires from any two of the three 120V phases. I guess we should speak technically because that's simpler - something like 208Y/120V.
 
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NateS

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I think you mean 120V three phase (not 208V three phase)? 208V is what you get when you combine the hot wires from any two of the three 120V phases. I guess we should speak technically because that's simpler - something like 208Y/120V.
Yes exactly, 120V/208Y I was referring to as just 208V, since in the context of powering servers, that's the voltage that's relevant. If you're just powering everything at 120V anyway, there's not much advantage to three phase over regular split-phase.
 
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Layla

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Yes exactly, 120V/208Y I was referring to as just 208V, since in the context of powering servers, that's the voltage that's relevant. If you're just powering everything at 120V anyway, there's not much advantage to three phase over regular split-phase.
Agreed and to my viewpoint, it's really all disadvantages except using less copper - except in exceptional circumstances, I'd prefer 240V for higher PSU efficiency. But those exceptions do exist - e.g. in my building we have 480V input like you mentioned, and if I wanted to add more power to my unit, the distance from the transformer room to my unit is long enough that 208Y/120V 3-phase would be a *lot* cheaper and simpler to install, and more likely to get approved.

Also, having access to three separate phases at 120V is very nice because if you use automatic transfer switches or multiple PSUs, you get redundancy against when the power company drops a phase, which has happened more than once in my city.
 

Layla

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Just a note: this three-phase PDU is metered but not "managed" like the single-phase one which the post was started about. I don't know which features are omitted on "metered" PDUs - possibly it's not switched? And possibly it's not metered-by-outlet? Eaton's website is unfortunately difficult to find details on...

I waited a while on the fence to buy these and ended up paying a lot more than OP as a result. Oops.
 
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