Review Index:

FSP Twins 500W Redundant Power Supply Review

Author: Lee Garbutt
Manufacturer: FSP Technology Inc.

Specifications and Packaging


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FSP 520W Modular PSU Nameplate

Each of the FSP power supply modules are rated for a continuous output power of up to 520 watts at 50°C and incorporate a single +12V output listed at 43.3A (519.6W). Note that the modular power supplies also include a +5VSB output.

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FSP Twins 500W PSU Nameplate

When two of these modules are combined into one Twins 500W unit, the combined total output power is listed as 500W. Circuits inside the common frame combine the outputs of the two modular power supplies and also generate the +3.3V, +5V, and -12V outputs. Note we now have three separate +12V outputs (thanks to the onboard current limiters), each rated at 16A.  The PSU includes universal AC line input (100-240 VAC, 50-60 Hz) and active PFC, which makes the unit more environmentally friendly to the local power grid.  

FSP 520W Modular PSU Specifications (from the FSP website):

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FSP Twins 500W PSU Specifications (from the FSP website):

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Packaging and Parts

The FSP Twins 500W redundant power supply arrived securely packed inside a large retail box highlighting the unit’s main features and specifications.  Inside the main box you will find two smaller boxes, one containing the common frame housing with fixed cables, and the other containing the two modular power supplies and a box of accessories.

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Once all the parts are unpacked and spread out you have the makings for a Twins 500W redundant power supply unit.

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The following two tables list the details of the included flat ribbon cables and connectors.

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(Courtesy of FSP)

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Video News

January 30, 2017 | 11:09 AM - Posted by Anonymous (not verified)

Do most redundant server PSUs operate in this fashion or keep one on standby?

January 30, 2017 | 12:03 PM - Posted by Anonymous (not verified)

Most of them can be configured to act either as a 1+1 (failover) or a 2+0 (both live).

January 31, 2017 | 05:17 AM - Posted by Anonymous (not verified)

If this cant be configured to be 1+1 then its kind of pointless.

I currently use a high end Seasonic with a APC UPS for reliability.

January 30, 2017 | 04:54 PM - Posted by Anonymous (not verified)

Whats the point of this? Really high price? I dont see the purpose for desktops. Better get an 1000Watt PSU single/

January 30, 2017 | 07:37 PM - Posted by Brox

Redundancy is the point of this.

January 31, 2017 | 04:08 PM - Posted by Anonymous (not verified)

Redundancy is exactly the point of this. I will most likely be buying 15 of them. Have been waiting for something like this forever!

When your production machines are 10,000$ per hour per line, having a power supply go out can cost thousands.

February 1, 2017 | 01:02 PM - Posted by LegoGuy (not verified)

So I've known that redundant PSU's have been standard in rack-mount cases for a long time, so what's the use-case for using these in standard ATX machines?
Rendering boxes, or other such machines?
I just legitimately don't know.

February 3, 2017 | 10:47 AM - Posted by Lee Garbutt

Anytime you have a PC running a mission-critical app or controlling high-value process equipment, you want to maximize up time by minimizing any potential hardware failures, like the PSU. I used to work in Bio-tech R&D and we frequently used redundant PSUs along with large UPSs on mass spec instruments and PCs running High Throughput Screening robotic systems. Any down time could cost thousands of dollars per hour.

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