Best Practices for Dell PowerEdge Server Power Supplies and UPSs

Summary: Best Practices for Dell PowerEdge Server Power Supplies and UPSs

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Symptoms

Problems related to the power supply of servers usually manifest themselves through one or more of the following behaviors:

🔴 Related to Power Supplies:

  • PSU alerts
  • Voltage mismatch alerts
  • Loss of redundancy of PSUs.
  • Reduced power available to the server.
  • Unexpected shutdowns.

🔴UPS related:

  • Server shutting down or exhibiting frequent power and/or PSU redundancy alerts
  • Operational instabilities with no apparent cause.
  • Progressive damage to PSUs or motherboard.

🔴Power related:

  • Recurring failures of power supplies.
  • Data corruption in HDDs or SSDs
  • Failure of motherboard, PIB, PSUs, and other electronic components.
  • Loss of settings, for example, of BIOS, iDRAC or Raid controller for example in more severe situations.
  • Premature component degradation and shortened equipment life.

Cause

1️⃣ Power PSUs at different voltages

A situation often encountered is the connection of redundant supplies from the same server at different voltages, for example, one PSU powered at 127V and another at 220V.

Although the server continues to operate, this condition can make redundancy unavailable, depending on the model of the PSU and Server, reduce the efficiency of the assembly, and cause unexpected behaviors and in the long term electrical damage to equipment.

In addition, supplies operating at lower voltages typically have lower power delivery capacity, which can limit the total capacity available to the equipment.

 

2️⃣ Use of common UPS or incompatible with Active PFC sources

Dell PowerEdge servers ( Generally 14th generation onwards) use Power Factor Correction (Active PFC) sources.

When these supplies are powered by UPSs with modified sine wave, simulated or square wave output, the PFC circuitry may not operate properly.

In these situations, it is common to observe shutdowns when the UPS enters the battery, excessive heating of the sources, instabilities and, in more serious cases, progressive damage to the components.

 

3️⃣ Undersized UPS

Another recurring cause is the use of UPSs with insufficient capacity to support the full load of the environment.

When the UPS operates close to or above its rated capacity, overloads, reduced range, and unexpected shutdowns may occur.

 

4️⃣ Oscillations and interruptions of the electrical network

Surges, undervoltages, frequent fluctuations, and power outages are one of the leading causes of hardware failure.

These events can directly impact power supplies, disks, motherboard and other electronic components, in addition to causing unavailability and data loss.

In recurrent situations, failures associated with power quality can characterize an environmental problem that can cause damage to servers.

 

Resolution

🔌 Standardize PSU power

Ensure that all power supplies in the same server are connected to the same input voltage.

Whenever possible, use 220V/230V circuits to power the PSUs, due to the greater energy efficiency and greater power availability that some models of PSUs have at this voltage.

 

💡 Use Pure Wave Sinusoidal UPS

In environments with PowerEdge servers, it is recommended to use pure-wave sinusoidal output UPSs.

Double conversion online pure wave sinusoidal UPSs are the most suitable, because regardless of the quality of the input power, they provide continuously conditioned energy and isolate the equipment from variations in the power grid.

 

⚡ Right-sizing the UPS

When selecting a UPS, consider in addition to being pure wave sinusoidal:

  • The total load of all connected appliances.
  • 20-30% margin of safety.
  • Autonomy time required.

In addition to reducing operational failures and increasing the useful life of equipment, an adequate electrical infrastructure avoids situations that can be classified as external factors during a warranty analysis, because when damage is caused by an inadequate environment and electrical events, these are not covered in warranty and can lead to a denial of warranty repair.

 

 
 
 
 

     
     
     
     

    Affected Products

    C Series, Rack Servers, Tower Servers
    Article Properties
    Article Number: 000484919
    Article Type: Solution
    Last Modified: 03 Jul 2026
    Version:  1
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