The AC PSU requires external surge protection devices for installations where electrical surges higher than
2KV common mode and 2KV differential mode are expected. Failure to do so can result in permanent damage
to the product.
The DC PSU requires external surge protection devices for installations where electrical surges higher than
2KV common mode and 1KV differential mode are expected. Failure to do so can result in permanent damage
to the product.
Note
Electrical Circuit Requirements
Each router requires a dedicated electrical circuit. If you equip the router with dual-power feeds, provide a
separate circuit for each power supply to avoid compromising the power redundancy feature.
The routers can be powered by a DC source. Ensure that equipment grounding is present and observe the
power-strip ratings. Make sure that the total ampere rating of all the products plugged into the power strip
does not exceed 80% of the rating.
Site Cabling Guidelines
This section contains guidelines for wiring and cabling at your site. When preparing your site for network
connections to the router, consider the type of cable required for each component, and the cable limitations.
Consider the distance limitations for signaling, ElectroMagnetic Interference (EMI), and connector
compatibility. Possible cable types are fiber, thick or thin coaxial, foil twisted-pair, or unshielded twisted-pair
cabling.
Also consider any additional interface equipment you need, such as transceivers, hubs, switches, modems,
Channel Service Units (CSU), or Data Service Units (DSU).
Before you install the router, have all the additional external equipment and cables on hand. For information
about ordering, contact a Cisco customer service representative.
The extent of your network and the distances between the network interface connections depend, in part, on
the following factors:
• Signal type
• Signal speed
• Transmission medium
The distance and rate limits referenced in the following sections are the IEEE-recommended maximum speeds
and distances for signaling purposes. Use this information as a guideline when planning your network
connections
prior to
installing the router.
If wires exceed the recommended distances, or if wires pass between buildings, give special consideration to
the effect of a lightning strike in your vicinity. The electromagnetic pulse caused by lightning or other
high-energy phenomena can easily couple enough energy into unshielded conductors to destroy electronic
devices. If you have had problems of this sort in the past, you may want to consult experts in electrical surge
suppression and shielding.
Cisco Network Convergence System 540 Large Density Routers Hardware Installation Guide
19
Prepare for Installation
Electrical Circuit Requirements
