The RIB2421B relay is a reliable solution for building automation, HVAC motor control, and lighting circuits. It supports a wide range of input voltages—24 Vac/dc, 120 Vac, and 208–277 Vac—making it a flexible choice for commercial installations. Its SPDT contact allows for simple switching, and it is ideal for isolating low-voltage control signals from high-voltage loads.
- Relays & Contact Type: One (1) SPDT Continuous Duty Coil
- Expected Relay Life: 10 million cycles minimum mechanical
- Operating Temperature: -30 to 140° F
- Humidity Range: 5 to 95% (noncondensing)
- Operate Time: 18ms
- Relay Status: LED On = Activated
- Dimensions: 2.30" x 3.20" x 1.80" with 0.50" NPT Nipple
- Wires: 16", 600V Rated
- Approvals: UL Listed, UL916, UL864, C-UL, California State Fire Marshal, CE, RoHS
- Housing Rating: UL Accepted for Use in Plenum, NEMA 1
- Gold Flash: No
- Override Switch: No
- 20 Amp Resistive @ 277 Vac
- 5 Amp Resistive @ 480 Vac
- 20 Amp Ballast @ 277 Vac
- 16 Amp Electronic Ballast @ 277 Vac (N/O)
- 10 Amp Tungsten @ 120 Vac (N/O)
- 770 VA Pilot Duty @ 120 Vac
- 1,110 VA Pilot Duty @ 277 Vac
- 2 HP @ 277 Vac
- 1 HP @ 120 Vac
Coil Voltage Input:
24 Vac/dc ; 120 Vac ; 208–277 Vac ; 50–60 Hz
Drop Out = 2.1 Vac / 3.8 Vdc
Pull In = 18 Vac / 22 Vdc
Coil Current:
83 mA @ 24 Vac
47 mA @ 120 Vac
69 mA @ 208–277 Vac
47 mA @ 30 Vdc
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Functional Devices RIB2421B Specifications |
- Mounting:
- Enclosed
- Number of Relays:
- 1
- Relay Contact Type:
- SPDT
- Relay Coil Voltage:
- 24 Vac/dc/120 Vac/208-277 Vac
- Contact Ratings:
- 20 Amp