Junior Single Down Pump Switch

SJE-Rhombus Junior Super Single® Pump Switch – Technical Product Information

The SJE-Rhombus Junior Super Single® Pump Switch is a mercury-activated float switch engineered for direct pump control in water and wastewater applications. Designed for automatic pump-down operation, this control device is rated for fractional horsepower motor loads and provides reliable level regulation in non-potable water, drainage, and light sewage environments. The switch is sealed for submersible use and factory-weighted to maintain consistent float positioning. Suitable for installations where compact float operation is required and electrical isolation of the control circuit is not necessary.

Technical Specifications

• Product Code: 1001896
• Model: 10JSD1WP
• Manufacturer: SJE-Rhombus
• Series: Junior Super Single®
• Switch Type: Mercury-Activated Float Switch
• Control Type: Pump-Down (Normally Open Configuration)
• Electrical Rating:
  • 120 VAC, 50/60 Hz – Up to 1/2 HP Motor Load
  • 230 VAC, 50/60 Hz – Up to 1 HP Motor Load
• Amperage Rating: 13 FLA / 85 LRA at 120 VAC
• Cord Type: SJEOW water-resistant cord, 16 AWG, with grounded plug (length varies by configuration)
• Mounting Configuration: Weighted mounting, designed for vertical or angled orientation in non-turbulent locations
• Operating Environment: Non-potable water, water, and light sewage applications
• Operating Temperature: Up to 140°F (60°C)
• Enclosure Rating: Watertight, corrosion-resistant construction suitable for submersible duty
• Performance Considerations:
  • Not rotation sensitive; must be installed away from turbulence for accurate actuation
  • Not recommended for use with motor contactors or relays due to potential chatter under inductive load
  • For systems requiring external relay operation, use Super Single® or Double Float® control models
• Compliance: UL Recognized for pump and control duty applications

Professional Summary

The SJE-Rhombus Junior Super Single® Pump Switch provides dependable liquid level control for small to mid-capacity pumps operating in non-potable water and light wastewater environments. Designed for direct motor switching up to 1/2 HP at 120 VAC, it integrates mercury-activated precision with rugged, sealed construction for long service life in demanding field applications. Ideal for sump, effluent, and transfer systems, the Junior Super Single® delivers consistent performance when properly installed in non-turbulent conditions. For control circuits requiring relay isolation or enhanced switching efficiency, higher-capacity Super Single® or Double Float® configurations are recommended.