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RIB Enclosed Pre-Wired Relay: 20 A Rating, 24V AC/DC/208-277V AC/120V AC, SPST-NO - General Purpose Power Relays
RIBGeneral Purpose Power Relays

RIB Enclosed Pre-Wired Relay: 20 A Rating, 24V AC/DC/208-277V AC/120V AC, SPST-NO

The RIB Enclosed Pre-Wired Relay is a general purpose power relay with a 20 A rating, offered by RIB. It features a SPST-NO contact configuration and a nipple size of 0.50 in NPT. The relay supports coil voltages of…

SKU 3G-OTH-37503

Brand
RIB
Item
Enclosed Pre-Wired Relay: 20 A Rating, 24V AC/DC/208-277V AC/120V AC, SPST-NO
Category
General Purpose Power Relays
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Technical Specifications

RIB
Manufacturer Part Number
RIB2421SB
Type
SPST-NO
NPT
0.50 in
Nipple Size
0.50 in NPT
Coil Voltage
24V AC/DC/208-277V AC/120V AC
AC/DC/208-277V AC/120V AC
24V
View Full Spec Sheet

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RIB Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The RIB Enclosed Pre-Wired Relay is a general purpose power relay with a 20 A rating, offered by RIB. It features a SPST-NO contact configuration and a nipple size of 0.50 in NPT. The relay supports coil voltages of 24V AC/DC, 208-277V AC, and 120V AC, as indicated by the manufacturer part number RIB2421SB.

Frequently Asked Questions

What is the RIB Enclosed Pre-Wired Relay used for?

The RIB Enclosed Pre-Wired Relay is a general purpose power relay used for switching loads in HVAC, lighting, and industrial control panels. Its 20 A rating and SPST-NO configuration make it suitable for on/off control of motors, pumps, and resistive loads in commercial buildings and process equipment.

What are the specifications of the RIB2421SB relay?

The RIB2421SB is a RIB enclosed pre-wired relay with a 20 A rating, SPST-NO contacts, and a 0.50 in NPT nipple. It supports coil voltages of 24V AC/DC, 120V AC, and 208-277V AC. The relay is designed for general purpose power switching in industrial and commercial applications.

Where to buy the RIB2421SB relay worldwide?

3G Electric supplies the RIB2421SB relay worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this RIB relay to any country.

How to select the correct coil voltage for a RIB relay?

Select the coil voltage that matches your control circuit: 24V AC/DC for low-voltage systems, 120V AC for standard North American controls, or 208-277V AC for higher-voltage commercial lighting. The RIB2421SB supports all three voltages in one unit, simplifying inventory and installation.

Used in

Common applications for RIB
HVAC control — RIB enclosed pre-wired relays (e.g., RIB2421C) for switching fan coils and damper actuators
Lighting control — RIB wireless relays (RIBW208B-EN3) for remote switching of high-bay or parking lot lighting
Pump monitoring — RIB adjustable current sensing relay (RIBXKTA) for detecting dry-run conditions in water pumps
Process automation — RIB 3PST-NO relays (RIB013P) for interlocking conveyor systems or motor starters
Building management — RIB wireless transmitter/receiver pairs for retrofitting legacy control panels without new wiring

RIB Products

3G Electric supplies RIB general purpose power relays. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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