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Black November

Black November


Munro Pump Start Relay for 1 Float Rainwater Harvesting System | MBRB241

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Sales Price $511.25 Our Price $957.95 You save 47%

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Simple and efficient, the BrainBox by Munro provides the pump control for rainwater harvesting. Through the use of simple float controls, the BrainBox synchronizes source water with pump requirements. If rainwater is available, the BrainBox uses the stored water first. if no rainwater is available, the BrainBox utilizes a domestic or alternate source to provide water to the pump during a run cycle.

The BrainBox by Munro monitors the balance of available water in a rainwater harvesting system against the water level needed to assure proper pump performance.

Features & Benefits

  • Completely automatic and hands-free pump protection.
  • Bridges the gap between 24 volt lawn controllers and 110/220V pump motors.
  • Serves as a pump start relay plus offers pump shut-down protection if source water is not available.
  • One model works for all pumps from 3/4 HP to 5 HP
  • Color coded wiring for easy installation
  • Float control (lower) verifies water is available during pump run cycle.
  • Float control (upper) supplements harvested water supply through the use of a domestic solenoid valve. (Solenoid to be supplied by others)
  • Low pressure sensor protects the pump if the inlet water flow is restricted, reduced, or completely blocked.
  • High temperature sensor protects the pump if the discharge is closed or blocked.
  • All sensors and in-tank floats use safe 24v power


  • Nema 3R
  • Powder-coated steel - Blue or Grey
  • Dimensions - 12" w x 12" h x 6" d

Electrical Rating:

  • Maximum 110/220 volt, 1 phase
  • 5 hp maximum when internal Thermal

Protection is present

  • Control voltage is 24v

External Devices:

  • Low Pressure Sensor - fixed at 20 psi
  • High Temperature Sensor - fixed at 105° F
  • Float Control - 13 amp @ 120/240 VAC with 16 AWG cord 55' length

Munro Brain Box Models:

More Information
Brand Munro
Voltage 110/240V
Type Pump Start Relay
Warranty 1 Year or 1000 Hours of Operation
Horsepower 3/4 - 5
Number Floats 1
Catalog (23.84 MB)
Brochure (783.95 kB)