Panasonic WJHDE300 WJHDE300 User Guide - Page 5

■ General The extension unit WJ-HDE300 can contain up to four hard disk drives per unit to add available disk space to the digital disk recorder WJ-HD316/WJ-HD309. Up to seven extension units can be connected to a digital disk recorder. The units can be operated in RAID level 5* mode for high tolerance to disk error. * RAID level 5 (Redundant Arrays for Independent Disks, independent data disks with distributed parity blocks) RAID level 5 regards 3 or more drives as one drive, and it is possible to read data by automatically attaching error correction data even though one of the drives is broken. (It is impossible to read data if 2 or more drives are broken.) RAID level 5 requires a minimum of 3 drives to implement. When using the RAID function, logical disk size of the extension unit will be as below. Logical disk size = Smallest size of the disk among the disks in the extension unit x (Number of the disks in the extension unit - 1) The actual space may be several percent lower than the logical space. * Important When set to RAID level 5, the digital disk recorder will not access the HDD preinstalled in it, but will access only the HDDs in the extension unit. ■ Precautions • Do not operate the appliance beyond its specified temperature, humidity or power source ratings. Do not use the appliance in an extreme environment where high temperature or high humidity exists. Use the appliance at temperatures within +5 °C to +45 °C (41 °F to 113 °F) and humidity below 85 %. The input power source for this appliance is 120 V AC 60 Hz. • Avoid shock and vibration Shock or vibration may damage the HDD. The HDDs are fragile especially when the HDD motors are revolving and the HDD POWER indicator lights. Be sure to turn off either switch: the POWER switch on the rear panel, or the HDD POWER switch inside the front lid: before you mount the unit into a rack or dismount it. Do not move the HDD for 30 seconds after turning off the power. • Pay attention to static electricity Put your hand on a metallic surface to discharge static electricity before installation. Do not touch components mounted on the HDD directly with your hand. Hold only the two sides of the HDD when installing. • Avoid condensation on the surface of the HDD. If this happened, do not turn on the power of the appliance and leave the appliance for around 2 hours. Wait until the dew evaporates in any of the following cases. • The appliance is moved to a place significantly different in temperature or humidity. • The appliance is moved out from an air-conditioned room. • The appliance is placed in an extremely humid place. • The appliance is placed in a room where a heater has just been turned on. • Consumable parts Contact your dealer about replacement when the time comes. A hard disk drive needs replacing after a certain length (depends on the model) of operation. Cooling fans also need replacing after around 20 000 - 30 000 hours of operation. • Do not block the ventilation opening or slots on the cover. To prevent the appliance from overheating, place it at least 5 cm (2 inches) away from the wall. • Avoid placing the unit on an inclined surface. Otherwise, malfunction or damage to the disk may occur. Place the unit horizontally. 5