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Glossary of Terms - All Terms

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Glossary Subsets


To release flow to prevent pressure being imposed on the system or a portion of the system.

Uninteruptabile Power Supply (UPS)

• A device to insure a constant power to critical circuits such as computer banks, or hospital lighting.
• Very susceptible to spikes and surges.

UL (Underwriter Laboratories)

An independent lab which certifies not only safety but function of electrical devices used in the U.S.A.

Unloading Valve

A valve which bypasses flow to tank when a set pressure is maintained on its pilot port.