Cable Routing; Power Connections; Cable Routing Calculation - HP Cluster Platform Introduction v2010 Introduction Manual

1.6.3 Cable Routing

Depending on your computer room layout and cable routing provisions (such as overhead
raceways), You might need to estimate cable routes and plan the routing of cables. Note that the
order configuration rules for a cluster do not provide you with much flexibility. The cable lengths
are determined by the configuration rules, which select the cables from a limited set of
predetermined lengths. Generally, there is more than adequate cable length to span any
point-to-point route in the cluster, although you might be constrained in routing. For example,
overhead routing might not be possible if the distance between the floor and the overhead cable
raceway is too large.
To determine the routing restrictions, do the following:
1. Determine the cable length limits for a specific model of interconnect. If you have already
generated an order for a cluster you are already aware of the cable lengths for the type of
cluster ordered. Otherwise, contact your HP support or sales office to determine the cable
length options. As a starting point for information about the HP Cluster Platform, go to the
following URL:
http://www.hp.com/techservers/
2. Estimate the cabling constraints for interrack connections, referring to the example presented
in Figure
• A = rack height (such as 2 meters for a 42U rack)
• B = distance from the bottom of the rack to the underfloor trough or raceway
• C = distance to the overhead cable raceway
• D = distance between the racks
In Figure 1-5, examples of the maximum cable run distances are shown by the dotted lines labelled
Overhead and Underfloor.
Figure 1-5 Cable Routing Calculation
C
D
CBB
A
B
Underfloor

1.6.4 Power Connections

Depending on the power consumption calculations, you might need to plan additional power
circuits for the cluster. Such work must be done only by certified and trained technicians and
should include verification of the following:
• Ground paths
• Voltage levels of completed circuits
1-5, where:
Overhead
D D D
CBB IBB CBB
D
CBB
1.6 Planning for Connections 29