HP rp5400 Site Preparation Guide - rp5400 - Page 14

General Site Preparation Guidelines Electrical Factors Raised Floor "High Frequency Noise" Grounding If a raised floor system is used, install a complete signal grounding grid for maintaining equal potential over a broad band of frequencies. The grounding grid should be connected to the equipment cabinet and electrical service entrance ground at multiple connection points using a minimum #6 AWG (16mm2) wire ground conductor. The following figure illustrates a metallic strip grounding system. Hewlett-Packard recommends the following approaches: • Excellent-Add a grounding grid to the subfloor. The grounding grid should be made of copper strips mounted to the subfloor. The strips should be 0.032 in. (0.08 cm) thick and a minimum of 3.0 in. (8.0 cm) wide. Connect each pedestal to four strips using 1/4 in. (6.0 mm) bolts tightened to the manufacturer's torque recommendation. • Better - A grounded #6 AWG minimum copper wire grid mechanically clamped to floor pedestals and properly bonded to the building/site ground. • 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 resistive 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. Figure 1-1 Raised Floor Metal Strip Ground System Ground wire to power panel Floor panel Hex bolt Grounding clamp Band and pedestal 6 Grounding grid element Grounding braid to computer equipment 60SP010A 11/30/99 Chapter 1