19Mounting the switch on a workbenchIMPORTANT:• Ensure good ventilation and 10 cm (3.9 in) of clearance around the chassis for heat dissipation.• Avoid placing heavy objects on the switch.To mount the switch on a workbench:1. Verify that the workbench is sturdy and reliably grounded.2. Place the switch with bottom up, and clean the round holes in 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.Grounding the switchWARNING!Correctly connecting the switch grounding cable is crucial to lightning protection and EMI protection.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 with a grounding conductor buried in the earth ground• Grounding the switch by using the AC power cordNOTE:The power and grounding terminals in this section are for illustration only.Grounding the switch with a grounding stripWARNING!Connect the grounding cable to the grounding system in the equipment room. Do not connect it to a firemain or lightning rod.If a grounding strip is available at the installation site, connect the grounding cable to the groundingstrip.Connecting the grounding cable to the chassis1. Remove the grounding screw from the rear panel of the switch chassis.2. Use the grounding screw to attach the ring terminal of the grounding cable to the grounding screwhole. Fasten the screw.
