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