Keeping data center standby gensets online during service

In a data center, standby power carries critical infrastructure when the grid cannot — cooling, networking and server systems that cannot pause, and any interruption during a filter change defeats the purpose of having backup power at all.

DAVCO Pro 692 Tall Duplex fuel/water separator. (Photo: DAVCO Industrial

Stored diesel is the vulnerability most operators underestimate. During storage, water, sediment and fuel degradation byproducts can accumulate within the tank. Water and contaminants, which are denser than diesel fuel, settle to the bottom of the tank. Over time, condensation, fuel aging and microbial activity can create sediments and sludge that threaten fuel quality.

A generator can sit idle for months, then poor fuel conditions can surface the moment it is needed most. Modern engines raise the stakes further; their injectors demand exceptionally clean fuel, and debris that reaches them can cause catastrophic failure.

One technology center in the Southeastern U.S. learned this directly. Poor stored fuel conditions plugged the stage 1 filter on its generator prematurely — doing exactly what a filter should, but forcing a shutdown that disconnected power to the critical infrastructure it protected. Even a sound fuel tank maintenance plan cannot fully prevent contamination in stored diesel, which is why a fuel/water separator belongs alongside it. The issue was not the filter; it was that servicing it meant taking the generator offline.

The facility moved to a DAVCO Industrial Pro 692 Tall Duplex system on its Cummins QSK60. The duplex design pairs two filters with isolation valves, so a technician can isolate and replace one element while the other keeps fuel flowing and the generator running. The filter media is built to pull water out of the fuel and hold a high volume of contaminants, and its clear covers let staff see filter condition before it becomes a problem.

That holding capacity also stretches service intervals — past 1,000 hours, roughly double the previous filters — a benefit that matters most in prime power or extended outage duty, when the generator runs long enough for interval length to count.

As the customer put it, the result was “peace of mind from not losing power while changing out the fuel water separator elements.”

For anyone specifying standby power, the lesson is straightforward: fuel quality cannot be guaranteed, but serviceability can be designed in. Duplex fuel/water separation keeps generators protected against contamination, and keeps them online during the maintenance that protection requires.

Rob Osgood is the director of Off-Highway Sales at DAVCO Technology, a U.S. manufacturer of diesel fuel filtration and water separation systems for on-highway and off-highway applications.