Connect the Grounding Cable
To meet safety and electromagnetic interference (EMI) requirements and to ensure proper operation, you must provide adequate grounding to the switch before you connect power.
The grounding points are in the form of studs sized for M5 Pan Head screws. The M5 Pan Head screws are provided in the accessory kit. The grounding points are spaced at 0.75-in. (19.1-mm) centers (see Figure 6).
You ground the switch by connecting a grounding cable to earth ground and then attaching it to the grounding points on the chassis by using two M5 Pan Head screws. You must provide the grounding cables; the cable lugs are provided with the switch.
The grounding lug accommodates 14–10 AWG (2–5.3 mm²) stranded wire. The grounding cable that you provide for the chassis must be the same size or heavier than the input wire of each power supply. Minimum recommendations are 14–10 AWG (2–5.3 mm²) stranded wire, 60°C wire, or as permitted by local code.
Grounding is required for models that use DC power supplies and recommended for models that use AC power supplies. An AC-powered switch gets additional grounding when you connect the power supply in the switch to a grounded AC power source outlet by using the power cord.
To connect earth ground to a switch:
A licensed electrician must attach the grounding lug to the grounding cable.
- Wrap and fasten one end of an ESD wrist strap around your bare wrist, and connect the other end of the strap to the ESD point on the switch.
- Ensure that all grounding surfaces are clean and brought to a bright finish before grounding connections are made.
- Connect the grounding cable to a proper earth ground.
- Detach the ESD grounding strap from the ESD point on the switch.
- Place the grounding cable lug over the grounding point
on the side of the chassis (see Figure 6).
Figure 6: Grounding Point on an EX9253 Switch1—Grounding point
- Secure the grounding lug on the grounding cable to the protective earthing terminal on the switch by using the screws (see Figure 7).
- Connect the other end of the grounding cable to a proper earth ground.
- Dress the grounding cable appropriately. Ensure that it does not touch the switch components, block the air exhaust and access to the switch components, or drape where people could trip on it.