39If a standard 19-inch rack is not available, you can place an S5820X switch (except the S5820X-26S) ona clean, flat workbench, as follows:1. Check that the workbench is sturdy and well grounded.2. Place the switch with bottom up, and clean the round holes on the chassis bottom with dry cloth.3. Attach the rubber feet to the four round holes in the chassis bottom.4. Place the switch with upside up on the workbench.IMPORTANT:• Ensure good ventilation and 10 cm (3.9 in) of clearance around the chassis for heat dissipation.• Avoid placing heavy objects on the switch.Grounding the switchWARNING!Correctly connecting the switch grounding cable is crucial to lightning protection and EMI protection.NOTE:The power and grounding terminals in this section are for illustration only.The power input end of the switch has a noise filter, whose central ground is directly connected to thechassis to form the chassis ground (commonly known as PGND). You must securely connect this chassisground to the earth so the faradism and leakage electricity can be safely released to the earth tominimize EMI susceptibility of the switch.You can ground the switch in one of the following ways, depending on the grounding conditionsavailable at the installation site:• Grounding the switch with a grounding strip• Grounding the switch in other grounding environmentGrounding the switch with a grounding stripConnecting the grounding cable for the S5820X-26S switchTo connect the grounding cable:1. Attach the two-hole grounding lug at one end of the grounding cable to a grounding point on theswitch chassis (see "Connecting the grounding cable to the switch chassis").2. Connect the OT terminal at the other end of the grounding cable to a grounding post on thegrounding strip, and fasten the grounding cable to the grounding post with a hex nut.