Quantum px720 User Guide

Glossary

Quantum PX720 User’s Guide

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to manage storage and retrieval. The format of the additional 

information is unique and is hidden from the initiator during 

normal read or write operations. This additional information is 

often used to identify the physical location of the blocks of data 

and the address of the logical block, and to provide protection 

against the loss of the user data. 
The address of the first logical block is zero. The address of the 

last logical block is [n-1], where [n] is the number of logical 

blocks available on the medium. A Read Capacity command may 

be issued to determine the value of [n-1]. If a command is issued 

that requests access to a logical block not within the capacity of 

the medium, the command is terminated with CHECK 

CONDITION. 

The CHM 

is a mechanical 

component of the extension axis assembly 

(robotics) which 

grips and holds a tape cartridge in transit.

This standard describes the emissions testing methods and 

test limits for information technology equipment, such as 

computers, office machines, or telecommunications equipment 

connected to low - voltage power main networks (<600V). It does 

not apply to equipment whose primary function is radio 

transmission or reception as defined by the International 

Telecommunications Union (ITU) Radio Regulations. 
The object of the standard is to establish uniform requirements 

for the conducted and radiated disturbance levels of the 

equipment covered by the standard. Disturbance limits are 

established for Class A and Class B equipment, and 

measurement methods, operating conditions, and interpretation 

of results are addressed. 

Class A equipment is intended for Commercial 

installation.

Class 1 lasers are products where the power of the 

laser beam produced (the accessible emission) is always below 

the Maximum Permissible Exposure value. Therefore, for Class 1 

lasers the output power is below the level at which it is believed 

eye damage will occur. Exposure to the beam of a Class 1 laser 

will not result in eye injury. Class 1 lasers may therefore be 

considered eye safe. 

Class 2 lasers are limited to a maximum output 

power of 1 mW. A person receiving an eye exposure from a Class