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This chapter provides safety information and describes the tasks you must perform before you install the Cisco Access Server 5100.
This chapter includes information on the following topics:
Follow these guidelines to ensure general safety:
Follow these guidelines when working on equipment powered by electricity.
Electrostatic discharge (ESD) can damage equipment and impair electrical circuitry. It occurs when electronic components are improperly handled and can result in complete or intermittent failures.
Always follow ESD-prevention procedures when removing and replacing components. Ensure that the chassis is electrically connected to earth ground. Wear an ESD-preventive wrist strap, ensuring that it makes good skin contact. Connect the clip to an unpainted surface of the chassis frame to safely channel unwanted ESD voltages to ground. To properly guard against ESD damage and shocks, the wrist strap and cord must operate effectively. If no wrist strap is available, ground yourself by touching the metal part of the chassis.
 | Caution For safety, periodically check the resistance value of the antistatic strap, which should be between 1 and 10 megohms. |
This section describes the requirements your site must meet for safe installation and operation of your system. Ensure that your site is properly prepared before beginning installation.
The Access Server 5100 is designed to be rack-mounted in a data processing or telecommunications environment.
When planning your site layout and equipment locations, use the precautions in the following sections to help avoid equipment failures and reduce the possibility of environmentally caused shutdowns. If you are currently experiencing shutdowns or unusually high errors with your existing equipment, these precautions may help you isolate the cause of failures and prevent future problems.
The following precautions will help you plan an acceptable operating environment for the Access Server 5100 and will help you avoid environmentally caused equipment failures:
The following tips will help you plan an acceptable equipment rack configuration:
Check the power at your site to ensure that you are receiving "clean" power (free of spikes and noise). Install a power conditioner if necessary.
| Caution To avoid damage from lightning and power surges, install proper grounding. |
The installation checklist lists the procedures for initial hardware installation of a new Access Server 5100. Make a copy of this checklist and mark the entries as you complete each procedure. Include a copy of the checklist for each system in your site log.
Installation checklist for site _______________________________________________
| Task | Verified by | Date |
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Installation checklist copied |
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Background information placed in the site log |
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Environmental specifications verified |
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Site power voltages verified |
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Installation site prepower check completed |
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Required tools available |
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Additional equipment available |
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Unit received |
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UniverCD or printed documentation received |
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Chassis components verified |
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Software version verified |
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Initial electrical connections established |
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ASCII terminal attached to the console port |
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Modem attached to the console port (for remote configuration) |
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Signal distance limits verified |
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Startup sequence steps completed |
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Initial system operation verified |
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LAN interface name ______________________________
Unit serial number ________________________
The site log provides a historical record of all actions relevant to the Access Server 5100. Keep the site log in an easily accessible place near the chassis where anyone who performs tasks has access to it. Use the installation checklist to verify steps in the installation and maintenance of your system. Site log entries might include the following:
The distance limitations for the IEEE 802.3 10BaseT specification indicate a maximum segment distance of 325 feet (100 m) at a transmission rate of 10 megabits per second (Mbps).
As with all signaling systems, EIA/TIA-232 signals can travel a limited distance at any given bit rate; generally, the slower the data rate, the greater the distance. Table 2-1 shows the standard relationship between baud rate and maximum distance.
| Data Rate (Baud) | Distance (Feet) | Distance (Meters) |
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2400 | 200 | 60 |
4800 | 100 | 30 |
9600 | 50 | 15 |
19200 | 25 | 7.6 |
38400 | 12 | 3.7 |
| Caution EIA/TIA-232 is often used at greater distances than those specified in Table 2-1. If you understand the electrical problems that can arise and can compensate for them, you might still be able to get good results; however, do so at your own risk. We recommend that you stay within the distances defined by the standard. |
The use of balanced drivers allows EIA/TIA-449 signals to travel greater distances than the
EIA/TIA-232 standard. Table 2-2 lists the standard relationship between baud rate and maximum distance for EIA/TIA-449 signals. These limits are also valid for V.35 and X.21.
| Data Rate (Baud) | Distance (Feet) | Distance (Meters) |
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2400 | 4,100 | 1,250 |
4800 | 2,050 | 625 |
9600 | 1,025 | 312 |
19200 | 513 | 156 |
38400 | 256 | 78 |
56000 | 102 | 31 |
T1 | 50 | 15 |
| Caution The EIA/TIA-449 and V.35 interfaces support data rates up to 2.048 Mbps. Exceeding this maximum could result in loss of data and is not recommended; do so at your own risk. |
When you run cables for any significant distance in an electromagnetic field, interference can occur between the field and the signals on the cables. This fact has two implications for the construction of terminal plant cabling:
If you use twisted-pair cables with a good distribution of grounding conductors in your plant cabling, emitted radio interference is unlikely. If you exceed the maximum distances, ground the conductor for each data signal; however, this practice is not recommended.
If you have cables exceeding recommended distances, or if you have cables that pass between buildings, give special consideration to the effect of lightning strikes or ground loops. The electromagnetic pulse caused by lightning or other high-energy phenomena can easily couple enough energy into unshielded conductors to destroy electronic devices. If your site has experienced this type of problem, consult experts in lightning suppression and shielding.
Most data centers cannot resolve the infrequent but potentially catastrophic problems just described without pulse meters and other special equipment. Take precautions to avoid these problems by providing a properly grounded and shielded environment, and electrical surge suppression.
To prevent EMI, consult experts in radio-frequency interference (RFI).
Before connecting the AS51 network application card (NAC) console and auxiliary ports, read the following sections.
The AS51 NAC has an RJ-45 console asynchronous serial port. This port connects to a terminal using an RJ-45-to-DB-25 adapter. Depending on the adapter used, this port becomes a data communications equipment (DCE) device or a data terminal equipment (DTE) device. To use the terminal as a console you should use a DCE RJ-45-to-DB-25 adapter. The default parameters for the console port are 9600 baud, 8 data bits, no parity generated or checked, and 1 stop bit. The console port does not support hardware flow control.
An RJ-45 auxiliary asynchronous serial port is included on the AS51 NAC. This port connects to a modem for network access using an RJ-45-to-DB-25 adapter. The adapter you use turns this port into a DCE device or a DTE device. For connection to a channel service unit/digital service unit (CSU/DSU) or protocol analyzer, you should use a DTE RJ-45-to-DB-25 adapter.
Read this section to prepare for your network connections.
Use 10BaseT cables and connectors to cable the AS51 NAC directly to the network.
The two asynchronous serial ports on the AS51 NIC use 68-pin SCSI connectors, providing connections for 8 asynchronous ports each. A breakout cable that divides into two 50-pin D-type connectors is connected to each asynchronous port.
Do not unpack the Access Server 5100 until you are ready to install it. If the final installation site will not be ready for some time, keep the chassis in its shipping container to prevent accidental damage. When you have determined where you want the Access Server 5100 installed, proceed with the unpacking.
The chassis, cables, UniverCD or printed publications, and any optional equipment you ordered might be shipped in more than one container. When you unpack each shipping container, check the packing list to ensure that you received the following items:
Inspect all items for shipping damage. If anything appears to be damaged, or if you encounter problems when installing or configuring your system, contact a customer service representative.
See the appropriate sections in this manual for specific instructions.
Posted: Tue Oct 1 03:58:11 PDT 2002
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