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Outline
1. Safety and Caution Notes
Avoid areas where ambient temperature exceeds 40 degrees Celsius or falls below 0 degrees Celsius, or
where the pump or tubing would be exposed to direct sunlight.
Disconnect the pump from electrical power source before performing any maintenance.
When working on or around a metering pump, always wear proper protective clothing and equipment as rec-
ommended by the supplier of the liquid being pumped.
Depressurize the discharge tubing before disconnecting the tubing or performing any maintenance on the
pump.
2. Principle of Operation
The ES series electromagnetic metering pump consists of a pump unit, a driving unit, and a control unit.
The drive unit is an electromagnetic solenoid. When the solenoid coil is energized by the control unit the
armature shaft moves forward due to the magnetic force of the solenoid. The shaft is attached to a PTFE
faced diaphragm which is part of the pump unit. The diaphragm is forced into the pump head cavity decreas-
ing volume and increasing pressure which forces liquid in the pump head out through the discharge check
valves. When the solenoid coil is de-energized, a spring returns the armature to its starting position. This
action pulls the diaphragm out of the head cavity increasing volume and decreasing pressure. Atmospheric
pressure then pushes liquid from the supply tank through the suction check valves to refill the pump head.