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Glossary of Terms - All Terms

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Glossary Subsets


A unit of electrical resistance. One volt will cause a current of one ampere to flow through a resistance of one ohm.

Open Center

A condition where pump delivery circulates freely to tank in the center or neutral position.

Open Circuit

An electrical circuit whose continuity has been interrupted, as by opening a switch.

Open Loop

A system that does not use feedback information to regulate performance.


A restriction, the length of which is small in respect to its cross-sectional dimensions.

Outer Ring

The outer part of a bearing that fits into the housing and contains the internal raceway for the rolling elements.

Overload Relay

A relay that responds to an electric load and operates at a pre-set value of overload. The unit senses the current to the motor.


The chemical reaction of elements with oxygen which cause corrosion or deterioration.