Site Preparation Guide, Second Edition - HP Integrity cx2620 Server

IMPORTANT: Regardless of the grounding connection method used, the raised floor should be

grounded as an absolute safety minimum.

HP recommends the following approaches to create an effective and safe 2-foot by 2-foot signal

reference grid::

Good Use the raised floor structure as a ground grid. In this case, the floor must be designed

as a ground grid with bolted down stringers and corrosion-resistant plating (to provide

low resistance and attachment points for connection to service entrance ground and

HP computer equipment). The use of conductive floor tiles with this style of grid

further enhances ground performance. The structure needs to be mechanically bonded

to a known good ground point.

Better Add a grounded #6 AWG (16mm) minimum copper wire grid mechanically clamped

to floor pedestals and properly bonded to the building or site ground.

Best Add a grounding grid to the subfloor. Build the grounding grid with copper strips

mounted to the subfloor. Use strips that are 0.032 inches (0.08 cm) thick and a minimum

of 3.0 inches (8.0 cm) wide.

Connect each pedestal to four strips using 1/4-inch (6.0-mm) bolts tightened to the

manufacturer’s torque recommendation.

Figure 2-1 Raised Floor Metal Strip Ground System

Ground wire

to power panel

Floor panel

Hex bolt

Grounding clamp

Band and pedestal

Grounding braid

to computer equipment

Grounding grid eleme

Equipment Grounding Implementation Details

Connect all HP equipment cabinets to the site ground grid as follows:

1. Attach one end of each ground strap to the applicable cabinet ground lug.

2. Check that the braid contact on each end of the ground strap consists of a terminal and

connection hardware (a 1/4-inch (6.0-mm) bolt, nuts, and washers).

28 General Site Preparation Guidelines