Peavey X-Eight HS, X-Eight RT Console and power supply grounding, Redundant power supplies

power supply 8

power supply usage

console and power supply grounding

Console chassis ground is electrically connected to: the audio ground, pin- 1 of XLR connectors, the sleeves of 1/4” sockets,and to the terminal CON- SOLE GROUND at the rear of the power supply.

The AC third-wire connection in the power supply cable connects the metal chassis of the power supply to safety ground.

Rack-mounting—the power supply ground may transfer to the rack case through the front fixing screws, though this connection is not reliable.

Sound system use—the grounding requirements may call for the ground link to be disconnected.This is permissible only when an alternative ground path has been provided. If in doubt seek the advice of an experienced elec- trical engineer.

This connection should never be disturbed.

Hazardous voltages exist inside the power supply which require the case to be grounded.

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redundant power supplies

The console power supply can be considered the single most important component in an entire sound system. If a power amplifier,a signal proces- sor or a console input goes down in the middle of a show, the show can still go on. But if the console loses its power supply, the show is over. For this reason, it is always good practice to incorporate redundant power supplies for mixing consoles used in professional sound reinforcement applications.

This should be considered a high priority even when using a very reliable power supply. In even the most carefully designed sound systems, each component runs the risk of failure at sometime or another.

Crest Audio uses two methods for attaching redundant power supplies to consoles. In both methods, the two (or more) power supplies should be kept on while the console is in use to insure a smooth transition in the event that one shuts off.

If one power supply drops in voltage or shuts off completely,the other unit takes over without any interruptions or audible glitches.As an added pre- caution,the two (or more) power supplies can be fed by separateAC lines. This will guarantee that the console does not shut off if one of theAC lines goes down.

multiple power supplies in-series

Crest Audio X-Series consoles use this method for backup. Since each power supply includes voltage switching circuitry,more than two units can be hooked up in series. A DC link cabel ties the power supplies together.

The use of redundant	+
power supplies is

probably the single biggest step that can be taken in reducing or eliminating the chance of a cancelled per- formance due to system failure.

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