Functional Devices RIB2401B Power Relay, 20 Amp SPDT, 24 Vac/dc/120 Vac Coil, NEMA 1 Housing

Used this Functional Devices RIB2401B relay to have an Ecobee Lite control a kerosene heater in my workshop to prevent freezing. Setup was simple — installed in minutes, and it’s handling 20A with no issues. I set it to maintain 40°F by offsetting the temperature delta and only trigger when it’s 3° below set point. Now I have full remote control, and the heater cycles exactly as intended. If you want to add smart control to a traditional heater or other high-current device, this relay makes it easy, reliable, and safe.

These are high quality manufactured relays! They work well. The only real issue with them is that they are hard to figure out which one you need for your application. They don't come with any documentation. The mfrs web site has some information, but read up on your application needs before choosing the model you need. There are many models to choose from. The only other thing to note is that some of the models do not engage immediately depending on the wiring of the circuit board in the box. I've seen some models with about a 1 sec delay, if this is important to you.

I'm using this to switch blower speeds in my older PSC blower furnace/AC depending on zoning calls, and it works perfect! Rock solid for nearly a year now.

This was the missing piece for my home solar setup. I have an EG4 3000EHV-48 inverter connected to two eco-worthy 48v rack-mount batteries (purchased from Amazon.com) and some solar panels. The issue was that the inverter does not have an internal Neutral to Ground bonding relay. In simple English, when I tried running my devices on battery, the electrical supply was unstable, the LED lights started flickering, etc. After months of research I was able to determine that the missing N-G bonding relay was the issue and I after more research the Functional Devices RIB2401B relay kept coming up as the relay to get to peform the simple task of monitoring my AC power (power from the electrical grid) on my main panel and then if there is a power outage, it would simply connect the Neutral and Ground wires in my load panel (devices to be powered by battery if I lose power). This worked perfectly, and I am finally able to enjoy my solar investment.

Normally, I've used Aube relays (e.g. RC840) for most of my applications (e.g. electric heating and circuit controls) and liked that they have external 24VAC / 24VDC coil connections. I've normally used these with Aube telephone controllers in single channel or 4 channel varieties. The Aube relays only have "NO" style contacts which means the contacts are only closed when the coil is energized ('normally open except when energized'). Since discovering these RIB2401B enclosed relays, I've been using these instead. They have the flexibility to operate the coils on 24 VAC, 24VDC as well on 110V. The major advantage is that the relay is a single pole double throw (SPDT) version that provides both NO (normally open except when energized) and NC (normally closed except when energized) contacts. Many of my applications are those where I am using the relay to provide near continuous power (such as for operating a camera circuit that may require an occasional power interruption). With the SPDT relay, it can be configured with the NC mode; normally closed contacts except when the relay is energized. Both the Aube and the RIB relays have an LED that lights when the coil is energized. Largest issue / negative is that the RIB don't have direct external terminal / connections for low voltage signal lines. You either need to mix your low voltage (i.e. 24 V) signal lines with the higher voltage (110V or more) lines within the electrical box or have the means to isolate these from each other. Part of the rationale for not having external connections was likely to prevent a hazard when using 110V for the coil. It might also be possible to run the coil wires out through a hole in the housing (only if using 24V for the coil).

Arrived earlier than promised and worked as expected. Good purchase!

So I am not an electrician, just a DIY guy - so take this with a grain of salt. But I liked this relay because you could attach it directly to the punch out box of a electric junction box. I used this relay in conjunction with a little giant water pump. Little Giant 554542 VCMX-20ULS-C - also purchased on amazon So my dehumidifier in the basement was always filling up and I had to dump manually. Instead I have the pump as the condensate catcher and it automatically kicks in every now and again based on a float switch to pump out the water to my sewer line. I found a nice tube already going in and just added a T. Not bad. But the water pump also has a float shutoff switch if it overflows. But that switch is low voltage. So I have a 24V transformer supplying the power, and this transformer can either fail the circuit open or fail the circuit closed. There is a nice diagram right on the front. I chose to fail open, but that was just my preference. So again, the transformer supplies the power, as long as the emergency float switch is not thrown, power flows to the 24v side of the relay, and 115v power is supplied to the new outlet to power the dehumidifier. BUT - if the pump starts overflowing, the 24v loop is cut, the transformer shuts off power to the 115v side, and the dehumidifier loses electricity and turns off. Pretty slick

Really easy to wire up. The only thing that I had issues with was determining the minimum DC voltage to close the gate. The inverter I worked with had a CV of 12vdc so I wired up a 24vdc boost converter for the contact side and it worked.

Using this for my second stage of heat to control a 240v 4000 watt heater. No concerns with the current running through it, the unit works flawlessly. Like the multiple hook up and voltage options. Get this if you need for controlling your higher current loads.

This relay is a beast and works every time its triggered not like the lesser quality ones I've bought in the past.

Works as expected, very versatile

I used this relay along with a 24 volt transformer to replace a defective circuit board on my household central vac system. I would have given this a 5 star but I had a great deal of trouble understanding the electrical drawing as to how to correctly wire this unit up. The relay came only with an extremely basic imprint of internal and external wiring on one of its sides. It would have been very helpful if more wiring diagrams had been included in the package. After several plus hours of frustration I finally did figure out the meaning of the wiring diagram and wired my system successfully. It works great!

Fit on junction box, works perfectly, no busing noise, and also n/o and n/c function, great value for the price