In a data center, redundancy is extremely important. Power, cooling, monitoring—every system must continue operating when something fails. That expectation shapes everything from tier certification targets to daily operations. It also puts a spotlight on the small components that make larger systems reliable.
Relays, current sensors, and power supplies are among those components. Specified and applied correctly, they're what keeps redundant systems online when it counts.
Why Redundancy Depends on Control Components
Data centers are built around layered redundancy: N, N+1, 2N. Those frameworks are often discussed in terms of generators, UPS systems, and cooling plants. But the control layer is just as important. If a control signal fails to transfer, a monitoring point goes dark, or a panel loses its low-voltage supply, even a well-designed redundant system can stumble.
Relays isolate, switch, and communicate between systems. Current sensors verify that equipment is actually running and, if properly configured, flag abnormal conditions before they escalate. Power supplies keep control panels energized and stable. Together, they form the foundation of a reliable control layer.
For data center managers, reliability is measured in uptime—often 99.999% or better. Their goals include fault-tolerant infrastructure, efficient HVAC and power integration, and seamless communication between electrical and building automation systems. Those goals depend on components that are reliable, straightforward to specify, and easy to integrate into existing systems.
Where Functional Devices Components Fit in Redundancy Design
Functional Devices manufactures a range of products used throughout data center control systems. Each plays a distinct role in supporting redundancy.
RIB® Relays: Control, Isolation, and Failover Signaling
RIB® (“Relay-In-a-Box”®) relays are pre-packaged, enclosed relays designed for field installation. In a data center environment, they are commonly used for power monitoring and failover signaling—detecting voltage presence across primary and backup feeds and signaling a transfer sequence or alarm condition when a primary source drops.
They also handle HVAC redundancy and staging, isolating control circuits and ensuring that backup CRAC or CRAH units engage when needed. In BAS applications, they provide the physical interface between field devices and controller inputs, ensuring clean, reliable signals across power, cooling, and alarm systems.
Current Sensors: Monitoring and Fault Detection
Current sensors—including current switches and current transducers—provide real-time visibility into whether equipment is running and how hard it is working. In data centers, where a failing motor or a stuck damper can cascade quickly into a larger problem, that visibility matters.
Current switches provide simple on/off confirmation, which is useful for verifying that a fan, pump, or compressor has actually engaged after a control signal is sent. Current transducers output analog signals proportional to the current level, enabling the BAS to track load trends over time, trigger alarms when readings fall outside defined thresholds, and catch developing faults before they become failures. Split-core designs simplify installation in live environments, since they clamp around existing conductors without interrupting circuits.
Power Supplies: Stable Low-Voltage Power for Control Panels
Control panels in data centers depend on reliable low-voltage power to keep relays, sensors, and controllers operational. Functional Devices offers both AC and DC power supplies designed for BAS panel applications.
AC power supplies combine a step-down transformer and circuit breaker in a single prepackaged enclosure, eliminating the need to source and install those components separately. DC power supplies provide 12V or 24V output for controllers and sensors that require DC power. In environments where panel space is limited and commissioning schedules are tight, consolidated, pre-tested components reduce installation time and eliminate potential failure points.
Built for Mission-Critical Environments
Across all three product categories, Functional Devices designs with the same priorities in mind: reliability, ease of installation, and consistent performance over long service life.
Pre-wired and prepackaged enclosures reduce installation time and wiring errors. Universal voltage options simplify inventory and design across mixed-voltage environments. Isolation between circuits protects sensitive BAS inputs and outputs from electrical noise and load-side faults. Compact form factors fit into crowded panels and equipment skids without consuming valuable space.
In data centers, where commissioning schedules are tight and mistakes are costly, those characteristics matter. For engineers and contractors, that means delivering consistent performance across hundreds or thousands of control points—every time.
Supporting Broader Verticals
While data centers are a natural fit, the same redundancy principles apply across other environments. Hospitals and healthcare facilities rely on redundant HVAC and power systems for patient safety. Schools and universities require dependable HVAC control across large campuses. Retail environments depend on lighting and refrigeration systems that cannot afford downtime. In each case, relays, current sensors, and power supplies act as the bridge between equipment and control logic.
Designing with Redundancy in Mind
Using control components effectively in redundant systems comes down to a few key considerations. Fail states should be defined clearly. Control paths should be separated to avoid single points of failure in wiring or logic. Isolation should be used strategically to protect BAS inputs and outputs from electrical noise or faults. And maintenance should be planned for from the start. Using components that are easy to replace and troubleshoot can make a real difference over the life of the system.
Frequently Asked Questions
What makes a relay suitable for data center use?
Reliability, ease of installation, and compatibility with multiple voltages and systems are key. Enclosed, pre-wired relays reduce field errors and simplify troubleshooting in live environments.
Can RIB® relays be used for power monitoring?
Yes. They are commonly used to detect voltage presence and signal changes in power conditions, including failover sequences between primary and backup feeds.
How do current sensors support redundancy?
By confirming that equipment has actually engaged after a control signal is sent, and by flagging abnormal current draw before it becomes a failure.
What role do power supplies play in data center control panels?
Power supplies provide the stable low-voltage power that keeps relays, sensors, and controllers operational. Prepackaged units that combine a transformer, breaker, and enclosure simplify installation and reduce the number of components that can fail.
Are these products compatible with BAS systems?
Yes. Functional Devices relays, current sensors, and power supplies are designed to integrate with standard BAS controller inputs and outputs without requiring additional gateways or converters.
Do these components require regular maintenance?
They are generally low-maintenance, but should be included in routine system checks as part of a broader reliability plan.
Talk to Functional Devices
Designing for redundancy starts with choosing the right components at every level of the system. If you are planning or upgrading a data center or any other mission-critical facility, Functional Devices can help.
Call us at 800-888-5538 or contact us online today.