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UCS B Series on 120V?

Level 4
Level 4

What are the options (if any) for running UCS B series setups on 120V?  I'm trying to build a small UCS configuration at home, primarily with M1/M2 era equipment, and the question of 120v options (I'd rather run a 120v circuit to the room in questino than 240 as the 120V will be more useful for resale) isn't quite clear.

Obviously, the UCS Mini with the newer model chassis and the UCSB-PSU-2500ACDV dual voltage power supply can run on 120V.  Can any other configurations run on 120V?  IE, could I take my old chassis, replace the existing power supplies with the newer UCSB-PSU-2500ACDV, and run 120V?  This site (  seems to say that even the old N20-PAC5-2500W power supply can run on 120v input voltage, but every one I've seen is only marked for 200-240v on the label, and I don't want to burn up equipment (or circuit breakers).

If I have to, I'll run 240v, or possibly consider replacing some equipment, but if I can run the following equipment on 120v somehow, possibly just with some new chassis PSUs, that'd be great

Equipment I have to choose from

C6508 Chassis

6120XP FI

6140XP FI

B200 M2

B250 M2

B230 M1


6 Replies 6

Paul Chapman
Level 4
Level 4

Hi -

Unfortunately the chassis power supplies will not accept less than 200V.  Applying lower voltage results with no power up and does not damage the equipment.

Contact a local electrician to set up a 208V outlet for you (in North America, a NEMA L6-30 is appropriate).  208V is the combination of (2) 120V phases that are already coming into your house.  (Common items that use 208V in your house are A/C, electric stoves and ovens.)


Thanks Paul.

It appears that the ACDV (120/208V) power supply in the UCS Mini and newer chassis does work in the old 5108 chassis, so anyone who is interested in running an older 5108 at home can make use of this to run things without needing a 208v circuit.  Obviously, you have half the wattage available though, so make sure to run it through the calculator and ensure you have enough power.

Thanks Joel. A year later, but just to confirm, the UCSB-PSU-2500ACDV will work with a N20-C6508 5108 Chassis?



Yet another year has passed, and this thread was the only one i could find confirming functionality.  Took a chance and now i can definitively confirm the original findings. In my home lab I'm running a legacy 5108 chassis (N20-C6508) with 4 B200 M2, and 4 B230 M3 blades.  I have 4 UCSB-PSU-2500ACDV plugged into 2 separate dedicated 25a 110 circuits.  Looks like the only question left on UCS mini backporting is if the 63k FIs will work without the intercommunication trace that was introduced on the new chassis.  Still a little too expensive for me to test.  Perhaps the next person trying this will complete the puzzle.  Hope this is helpful to anyone in the future. 

Glad to have this thread. I have the same legacy chassis. I am going to swap out the 208v power supplies for four Delta 120/240v units. It will have 2-B200 m3's and a B260 m4. Which eventually I hope to convert to a B460 later. I have 2- 2208xp's in the rear. That I wish were 6324's instead. I'll switch later on that one. I have a Cisco UCS-FI-6248UP and a Catalyst 2963 -L3.

Hopefully will be firing it all of tomorrow.

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