Edwards (EC2-RB4) 4″ relay base, ec2 series.

The Edwards EC2-RB4 is a 4-inch round relay base for EC2-series conventional smoke and heat detectors. First, it provides one Form C dry relay contact that follows the alarm state of the installed detector head. As a result, integrators can drive auxiliary loads such as door holders, HVAC shutdowns, or signaling relays from a single detector.

Edwards EC2-RB4 function

The detector head plugs into the base. Then, when the head reports alarm, the on-board relay transfers from its normal position. In addition, the dry contact provides isolation from the detector’s two-wire initiating circuit. Therefore, the contact can switch loads at different voltage levels than the detection circuit.

What this base is, and is not

The EC2-RB4 is a conventional two-wire detector accessory. Specifically, it pairs with Edwards EC2-series conventional photoelectric smoke heads and EC2 heat detectors. As a result, it does not address an intelligent loop, and it does not provide SLC communication. For Signature Series intelligent relay bases, see SIGA-RB / SIGA-RB4 instead.

Verified specifications

• Type: 4-inch round relay base for EC2-series conventional detector heads
• Relay: one Form C dry contact, normally-open and normally-closed terminals available
• Compatible heads: Edwards EC2 conventional photoelectric smoke and heat detectors
• Mounting: 4-inch octagonal or 4-inch square electrical box
• Construction: white thermoplastic housing

Application notes

The EC2-RB4 is appropriate for two-wire conventional fire alarm systems. First, verify the host fire alarm control panel supports a two-wire compatible detector on the intended zone. In addition, observe NFPA 72 spacing rules for the underlying EC2 detector head. Furthermore, isolated relay contacts must respect any maximum-current limit published with the base.

For more information, contact the Life Safety Consultants team at (888) 557-0558, or email us at: sales@lifesafetycom.com