IBM DS4700 manual Handling fibre-optic cables

CAUTION:

When laser products (such as CD-ROMs, DVD drives, fiber optic devices, or transmitters) are installed, note the following:

vDo not remove the covers. Removing the covers of the laser product could result in exposure to hazardous laser radiation. There are no serviceable parts inside the device.

vUse of controls or adjustments or performance of procedures other than those specified herein might result in hazardous radiation exposure.

DANGER

Some laser products contain an embedded Class 3A or Class 3B laser diode. Note the following.

Laser radiation when open. Do not stare into the beam, do not view directly with optical instruments, and avoid direct exposure to the beam.

Handling fibre-optic cables

Attention: To avoid damage to your fibre-optic cables, follow these guidelines:

vFor devices on slide rails, leave enough slack in the cables so they do not bend to a diameter of less than 76 mm (3 in.), or a radius less than 38 mm (1.5 in.), when extended or become pinched when retracted.

vDo not overtighten the cable straps or bend the cables to a diameter of less than 76 mm (3 in.), or a radius less than 38 mm (1.5 in.).

vWhen storing excess or unused fibre-optic cables, do not bend the cables to a diameter of less than 76 mm (3 in.), or a radius less than 38 mm (1.5 in.) or wrap them around themselves. See Figure 33 on page 58.

vLoop diameter of 76 mm (3 in.) and bend radius of 38 mm (1.5 in.) for fibre-optic cables are IBM DS4000 recommended minimums. Loops or bends smaller than this recommendation may cause damage to your fiber optic cables. It is best practice to use loop diameters and bend radii that are greater than these recommended minimums.

vDo not route the cable along a folding cable-management arm.

vRoute the cable away from places where it can be damaged by other devices in the rack cabinet.

vDo not put excess weight on the cable at the connection point. Be sure that the cable is well supported.

vDo not use plastic cable ties in place of the provided cable straps.

vThe following are the supported maximum cable lengths:

–1 Gbps: 500 meters 50/125 um fiber, 300 meters 62.5/125 um fiber

–2 Gbps: 300 meters 50/125 um fiber, 150 meters 62.5/125 um fiber

–4 Gbps: 150 meters 50/125 um fiber, 70 meters 62.5/125 um fiber

Chapter 3. Cabling the storage subsystem 57