Using AUDIT-BUDDY in the Battery Room: What Happens When the Power Goes Out?
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Battery rooms aren’t usually the first place operators think of when they hear “thermal monitoring.” But maybe they should be. These rooms house the UPS batteries that keep IT loads alive when the lights go out, and their performance depends heavily on how well they’re managed thermally.
So what happens when you run a pull-the-plug test—a simulated power failure—inside the battery room? That’s where a tool like AUDIT-BUDDY can turn guesswork into action plan.
Why Test the Battery Room at All?
During a pull-the-plug test, HVAC is shut down while the UPS takes on the IT load. For ten to fifteen seconds—or sometimes longer—the batteries are on their own. The room heats up and the whole system has to recover once power is restored.
Key questions operators should be asking:
How fast does the ambient room temperature climb with HVAC off?
What happens to the battery cabinet internal temperatures under discharge?
How long does it take for both the room and the cabinets to return to baseline after the event and recharge cycle?
Without solid data, the answers are often just assumptions.
Temperature Matters More Than You Think
Industry guidelines are fairly consistent:
Optimal ambient temperature: 72°F–77°F (22°C–25°C)
Acceptable range: 68°F–80°F (20°C–27°C), but prolonged time above 77°F shortens battery life.
Why? Because higher temps accelerate chemical reactions and cut lifespan, while lower temps reduce discharge efficiency. A simple rule of thumb: every 18°F (10°C) rise above optimal roughly halves the life of a VRLA battery.
And it’s not just about the room average. Internal cabinet temperature should mirror the room closely. Hotspots or thermal gradients across strings and tiers can quietly chip away at performance and reliability.
Where AUDIT-BUDDY Fits In
Representation of AUDIT-BUDDY in a Battery Room.
Here’s the challenge: a handful of sensors scattered across a battery room don’t tell you the full story. Airflow is uneven. Cabinets don’t heat uniformly. Recovery rates can vary.
AUDIT-BUDDY makes it possible to capture that nuance:
Place units strategically across the room and inside cabinets
Measure both ambient and cabinet-level responses during outage and recovery
Spot hotspots or lagging areas that single-point sensors miss
Generate clear, exportable data for reporting, analysis, or CFD validation
In short, it gives you the cabinet-level visibility needed to separate healthy rooms from ones that are slowly cooking their batteries.
What You Might Find (Hypothetical Scenarios)
Short outage (5 minutes): Ambient rises ~2°F, cabinets lag slightly behind. Safe recovery.
Longer outage (30 minutes): Ambient climbs 5°F, top-tier battery strings heat up disproportionately, recovery is slow.
Recharge cycle stress: After power returns, internal cabinet temperature ticks up another 1–2°F from the charging process before finally normalizing.
None of these scenarios are catastrophic—but over time, repeated stress can shave years off battery life.
Best Practices Going Forward
Use distributed sensors across cabinets, not just one per hall.
Log frequently enough to catch transient changes.
Watch for uneven cabinet responses—uniformity matters.
After a test, review the thermal curve, not just the peak value.
Conclusion
Battery rooms may be “behind the scenes,” but they’re as mission-critical as any server hall. With GPU-driven IT loads raising the stakes across facilities, even a small blind spot in UPS thermal management can mean lost uptime, lost efficiency, or lost asset life.
AUDIT-BUDDY gives you a simple, portable way to shine light on those blind spots. Whether you’re simulating a power failure, validating airflow strategies, or just benchmarking your environment, the right data makes all the difference.
Curious what you’d find in your battery room? Schedule a free 30-minute consultation with Purkay Labs’ thermal experts today.
About Purkay Labs
Purkay Labs develops simple, targeted tools to validate cooling and airflow strategies in operational data centers. Our flagship product, AUDIT-BUDDY, is a portable temperature and humidity monitor used by operators, engineers, and facility managers for rack-level spot-checks, commissioning, and troubleshooting.
We also provide thermal surveys, resiliency testing, and consulting services nationwide—helping data centers bridge the gap between today’s cooling strategies and tomorrow’s infrastructure.