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Starting Price: $3,730.00
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  • 3,000 psi max. discharge pressure
  • Max. temperature (contact factory for higher temperatures):
    • 316SS: 200°F
    • PVC: 125°F
  • 0.80 gph (3.03 L/h) to 34 gph (128 L/h) capacity
  • PTFE diaphragm
  • 1/2hp-1ph-60hz 115VAC-TEFC-48Y standard motor


The Neptune 500-S Series Chemical Metering Pump includes a micrometer dial and liquid head. The 500-S series of simplex pumps can also be configured in duplex via the 500-D series. 

The 500-S Series pump features a variable Oil By-PassTM stroke adjustment mechanism that will allow better valve performance than variable linkage designs. The valve checks have extra time to seat even in heavy liquids since they are idle during the bypass portion of the suction and discharge strokes. 

The ten-turn micrometer dial is calibrated in 1% increments, is bright and color-contrasted, and is protected from corrosion by a clear PVC covering. The stroke mechanism only moves when an adjustment is made, eliminating wear. The piston is powered through complete stroke length at all capacity adjustments, eliminating the stress, wear, and shock of lost motion designs.

The standard, integrally-mounted motors are totally enclosed and fan-cooled, with built-in automatic thermal overload. An internal relief valve automatically protects the piping and system from overpressure. The EZE-CleanTM valve system allows valve removal for cleaning without disturbing the piping to the pump. 


This product can be used in the following applications: