Series-781

Supported Applications

The Dwyer Series 781 & 782 Ice Cube Relays are full-featured relays designed for AC or DC circuits, capable of handling loads up to 15 amps. Documented applications include refrigeration compressor systems, HVAC motor controls, and water/wastewater pump control.

Operating Conditions & Performance

The series operates within an ambient temperature range of -40 to 131°F (-40 to 55°C) with a storage limit of -40 to 185°F (-40 to 85°C). Electrical ratings vary by model and standard: Series 781 models are rated for 15 A @ 277 VAC (50/60 Hz) or 28 VDC. Series 782 models support 15 A @ 120 VAC 50/60 Hz; 12 A @ 277 VAC 50/60 Hz or 28 VDC (UL); and 10 A @ 277 VAC 50/60 Hz (CSA). The relays feature silver alloy plug-in contacts with a cycle life of 100,000 cycles (electrical) and 10,000,000 cycles (mechanical).

Configuration Options

The series offers configurable input voltages including 24 VAC, 120 VAC, 240 VAC at 50/60 Hz for AC operation and 24 VDC. Key features include a flag status indicator and an LED status lamp for visual confirmation of relay state. A color-coded push-to-test button differentiates between AC and DC actuated models, with a removable lock-down lever to hold the test button in place.

Available options and accessories:

• Housing Material: Plastic polycarbonate
• Mounting: Socket-mounted for quick installation and replacement (clear plastic housing allows viewing of contacts)
• Sockets: Model 70-781D5-1A for Series 781; Model 70-782D8-1A for Series 782
• Approvals: CE, CSA, cULus, cURus

Key Product Differences

The series comprises two primary model families with distinct electrical ratings and physical dimensions. Series 781 models (e.g., 781XAXRM4L-) are SPDT relays measuring 1-19/32 [40.60] x 35/64 [14.00] x 1-3/32 [27.09]. Series 782 models (e.g., 782XBXRM4L-) are DPDT relays measuring 53/64 [21.00] x 1-3/32 [27.90] x 1-17/32 [39.10], with a socket dimension of 19/64 [7.37] x 1/64 [0.50] x 3/16 [4.75]. Power consumption differs by series: Series 781 consumes 0.9 VA; 0.7W, while Series 782 consumes 1.2 VA; 0.9W.