The Functional Devices RIBU1C-N4 is a 10-amp SPDT pilot control relay in a NEMA 4 housing, designed for wet locations, outdoor installations, and industrial control panel applications. The NEMA 4 rated enclosure version for applications where the relay will be exposed to water, splashing, condensation, or outdoor conditions. Carries UL508 listing for industrial control equipment. It accepts two independent coil voltage inputs — 10-30 VAC/DC on the white/blue leads and 120VAC on the white/black leads — covering virtually every HVAC control voltage without stocking multiple coil variants. Gold flash contacts ensure reliable signal-level switching, and the relay carries Functional Devices' 10-year warranty with a rated mechanical life of 10 million cycles minimum.
Best for: Wet locations, outdoor installations, and industrial control panel applications requiring a 10-amp SPDT pilot relay with dual coil voltage flexibility and NEMA 4 rated housing.
The RIBU1C-N4 is backed by Functional Devices' industry-leading 10-year warranty — the longest standard warranty in the RIB product line. Functional Devices reports a field failure rate of approximately 1 in 16,000 units.
When to Specify the RIBU1C-N4 vs. Standard RIBU1C
The RIBU1C-N4 is electrically identical to the standard RIBU1C — same dual coil voltage input, same 10-amp SPDT contacts, same gold flash contacts. The difference is the NEMA 4 rated enclosure and UL508 listing. NEMA 4 provides protection against windblown dust, rain, splashing water, and hose-directed water. Specify the RIBU1C-N4 when the relay will be mounted in outdoor enclosures, mechanical rooms with wash-down conditions, rooftop equipment installations, or any location where the NEMA 1 housing is not rated for the environment. For standard indoor HVAC and BAS panel applications, the standard RIBU1C or RIBU1C-RD is appropriate.
RIBU1C
Standard grey NEMA 1 housing. UL Listed, UL916. Plenum accepted. The most widely specified version for commercial HVAC and BAS applications.
RIBU1C-RD
Red enclosure. UL864 and California State Fire Marshal listed. Required for fire alarm and smoke control circuit applications.
RIBU1C-N4
NEMA 4 enclosure for wet, outdoor, and wash-down locations. UL508 listed for industrial control equipment.
| Wire Color | Function | Notes |
|---|---|---|
| White / Black stripe | 120VAC Coil Input | Use for 120VAC control circuits. Cap white/blue leads when using this input. |
| White / Blue stripe | 10-30 VAC/DC Coil Input | Use for 24VAC BAS outputs or 10-30VDC signals. Cap white/black leads when using this input. |
| White / Yellow stripe | Common (Comm) | Common terminal for SPDT contact circuit |
| Blue | N/C — Normally Closed | Connected to Common when coil is de-energized |
| Yellow | C — Contact | Switching contact output |
| Orange | N/O — Normally Open | Connected to Common when coil is energized |
| Specification | Value |
|---|---|
| Part Number | RIBU1C-N4 |
| Contact Configuration | SPDT (Single Pole Double Throw) — 1 Relay, Continuous Duty Coil |
| Coil Voltage Input | 10-30 VAC/DC and 120VAC (dual input, 50-60 Hz) |
| Pull In Voltage | 9 VAC / 10 VDC |
| Drop Out Voltage | 2.1 VAC / 2.8 VDC |
| Coil Current — 10 VAC | 33 mA |
| Coil Current — 24 VAC | 46 mA |
| Coil Current — 120 VAC | 28 mA |
| Contact Rating — Resistive | 10A @ 277VAC | 10A @ 28VDC |
| Contact Rating — Pilot Duty | 480 VA @ 240-277VAC | 480 VA Ballast @ 277VAC |
| Contact Rating — Tungsten | 600W @ 120VAC N/O | 240W @ 120VAC N/C |
| Contact Rating — Motor | 1/3 HP @ 120-240VAC N/O | 1/6 HP @ 120-240VAC N/C | 1/4 HP @ 277VAC N/O | 1/8 HP @ 277VAC N/C |
| Electronic Ballast | Not rated for electronic ballast |
| Operate Time | 20ms |
| Expected Relay Life | 10 million cycles minimum (mechanical) |
| Gold Flash Contacts | Yes |
| Status LED | Yes — On = Relay Activated |
| Override Switch | No |
| Housing Rating | NEMA 4 |
| Enclosure Color | Grey |
| Conduit Hub | 0.50” NPT |
| Dimensions | 1.70”H x 2.80”W x 1.50”D |
| Lead Wires | 16”, 600V rated |
| Operating Temperature | -30 to 140°F |
| Humidity Range | 5 to 95% non-condensing |
| Approvals | UL Listed, UL508, C-UL, CE, RoHS |
| Origin | Made of US and non-US parts |
| Warranty | 10 Years |
| Bulk Ordering | Add -10PACK, -25PACK, or -100PACK to part number |
Outdoor Equipment Control
NEMA 4 housing protects against rain and windblown water in outdoor HVAC and mechanical equipment installations
Rooftop Unit Control
Mounts directly on rooftop equipment where condensation and weather exposure would compromise NEMA 1 housings
Mechanical Room Wash-Down
NEMA 4 rated for hose-directed water and splashing, suitable for boiler rooms and mechanical spaces with wash-down maintenance
Industrial Control Panels
UL508 listing meets industrial control panel requirements where stricter enclosure ratings are specified
Cooling Tower Applications
Wet environment and condensation resistance for relay installations near cooling towers and evaporative equipment
BAS Outdoor Sensor Interfaces
Outdoor BAS binary output switching where the relay point is located outside the main control panel enclosure
Important — Electronic Ballast Rating & Coil Input Selection
The RIBU1C-N4 is not rated for electronic ballast loads. Use for standard magnetic ballast and pilot duty rated loads only. When wiring the coil, use only one coil input at a time — either the 10-30 VAC/DC leads (white/blue) or the 120VAC leads (white/black). Cap off the unused leads. Never energize both coil inputs simultaneously.
- Mounting:
- NEMA 4/4X Housing
- Number of Relays:
- 1
- Relay Contact Type:
- SPDT
