If you’ve worked with RIB® relays, you’ve likely noticed the small red LED on the device—but do you know what it really means? While red lights often signal a warning, that’s not the case here. The red LED on a RIB® relay is a simple but powerful feature designed to make installation, troubleshooting, and system diagnostics easier for installers and technicians. In this post, we’ll clear up common misconceptions about the red LED and explain how it helps you quickly assess your system’s status.
Answers at a Glance
Q: What does the red LED on a RIB® relay indicate?
A: The red LED means the relay coil is energized—it’s an indicator that the control signal has activated the relay.
Q: Does the red LED mean there’s a problem?
A: No. Unlike other red indicators, the LED on a RIB® relay is a status light, not a warning. It simply confirms the coil is receiving power.
Q: How does the LED help with troubleshooting?
A: If the red LED is ON but the connected load isn’t operating, it helps you narrow down issues—such as a locked motor, power loss, or a wiring fault.
Q: Is the red LED feature included on all RIB® relays?
A: Almost all RIB® relays include the red LED, but a few specialty models may differ. Check the datasheet or contact us if you’re unsure.
Q: Why did Functional Devices add the red LED to RIB® relays?
A: To make installation and diagnostics faster and easier for technicians—saving time, money, and hassle in the field.
Ease and Convenience
First, the aim with RIB relays, and Functional Devices as a whole, is to make installation easy and convenient for the field technicians and installers. The benefit of RIB relays is that they're offered in pre-packaged, pre-wired, and UL approved formats. This saves time and money when it comes to installation. One way we thought of passing savings on to you is by incorporating the red LED on our relays.
Typically, some kind of visual indicator of relay coil status is incorporated in any relay installation. This visual indicator says to the outside world, "Hey world, my coil is being energized!" Over the years, Functional Devices has listened to feedback, determining that our relay products are higher quality when an LED is added to the construction.
LED On = Energized Coil
Contrary to what a red light typically means (i.e. stop, warning, etc.) the red LED on our RIB relays signifies that the coil of the relay is being energized. It does not mean that there is something wrong with the RIB relay. That can be an important detail when debugging the system using the RIB relay. For example, let's say that a RIB2401B relay is controlling a fan motor. The building automation system (BAS) is calling for the fan to turn on. The red LED is illuminated, however, the fan is not turning. What could be happening in this system?
- Is the motor locked up?
- Is the power to the motor down?
- Is the motor too large a load, and have the relay contacts seized?
While that list is not exhaustive, it certainly narrows down the possible issues which then helps to debug the system. When the problem is determined quickly, it means a solution may quickly be implemented to bring everything back to normal.
Contact Us With Any Questions!
The red LED on RIB® relays is a simple yet essential feature that helps installers and technicians confirm relay operation at a glance. Far from signaling a fault, it shows that the relay coil is energized and ready to control your load. If you ever have questions about your RIB® products or need help with troubleshooting, our support team is always just a call or email away!
About Functional Devices, Inc.
Functional Devices, Inc., located in the United States of America, has been designing and manufacturing quality electronic devices since 1969. Our mission is to enhance lives in buildings and beyond. We do so by designing and manufacturing reliable, high-quality products for the building automation industry. Our suite of product offerings include RIB relays, current sensors, power controls, power supplies, transformers, lighting controls, and more.
We test 100% of our products, which leads to less than 1 out of every 16,000 products experiencing a failure in the field.
Simply put, we provide users of our various products confidence and peace of mind in every box.