Exabyte 230D Library Installation And Operation Manual page 152

Chapter 7
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138
If you are replacing a second drive, make sure the symbol on
the new drive (HVD or LVD) matches the symbol on the
already installed drive.
The SCSI symbols that distinguish between high-voltage
differential (HVD) and low-voltage differential (LVD) are
shown in the following figure.
High-voltage differential (HVD)
When the tape drive carrier is almost completely inside the
slot in the library, you will feel some resistance. This is caused
by the connection between the tape drive and the library's
drive interface card. To seat the connection, push firmly
against the drive until you can push no further.
Using a # 2 Phillips screwdriver, attach the two captive screws
so that the drive carrier is secured to the library. Tighten the
screws to 8.0 inch-pounds (9.2 kg-cm) of torque.
Low-voltage differential (LVD)
Exabyte 230D