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Before you can install the chassis, you must consider and implement certain prerequisites. This chapter includes the following preinstallation requirements:
To ensure general safety, follow these guidelines:
 | Warning Metal objects will heat up when connected to power and ground. This heated metal can cause serious burns or can weld to a terminal. |
The successful installation of the chassis should not require access to the chassis interior; however, if this becomes necessary, the following warning will appear at the beginning of any related procedures:
| Warning Before accessing the chassis interior, turn off power to the chassis and unplug the power cord. Use extreme caution around the chassis because potentially hazardous voltages are present. |
Failure to observe this warning and act accordingly may increase the potential for shock hazard or electrocution. Before beginning a procedure that requires access to the chassis interior, it is strongly advised that you read through the entire procedure. After you read the procedure, if you have any doubts about your ability to perform any part, contact a customer service representative for information on how to proceed.
Following are basic guidelines for working near electricity:
In addition, use the following guidelines when working with any equipment that may be connected to a power source and is still connected to telephone wiring or other network cabling.
Electrostatic discharge (ESD) damage, which occurs when electronic components are improperly handled, can result in complete or intermittent failures. ESD can impair electronic circuitry and equipment. Typically, the successful installation of the chassis should not require handling any components; however, always follow ESD prevention procedures.
 | Caution To prevent ESD damage, attach an ESD wrist strap before handling any components. The chassis power cord must be connected, but to prevent shock hazard, the power must be turned off. |
Following are the guidelines for preventing ESD damage:
Step 1 Slip on an ESD wrist strap, ensuring that it makes good skin contact.
Step 2 To safely channel unwanted ESD voltages to ground, connect the wrist strap to an unpainted chassis frame surface or another proper grounding point or surface.
Step 3 Use the edge ejectors to remove the card. Handle the card by its sides. Place the card on an antistatic surface or in a static shielding bag. To prevent further damage to the card by ESD voltages, defective cards must remain in the static shielding bag if they will be returned for repair or replacement.
Step 4 Handling the new card by its edges only, insert it into the chassis. Avoid contact between the card and clothing. The wrist strap only protects the card from ESD voltages on the body; ESD voltages on clothing can still damage the card.
To preclude unintended shutdowns, the chassis should be properly installed and maintained. The chassis has an internal blower that pulls air through the card cage from left to right (with the chassis front facing you). The chassis is designed to operate in a level, dry, clean, well-ventilated, and air-conditioned environment. If either the intake or exhaust vents are blocked in any way, this air-cooling function will be impaired, and the CSC-ENVM card, sensing this, will shut down the chassis. While purposeful chassis shutdown due to a fault or failure is a function of the CSC-ENVM card, unnecessary shutdowns due to air intake blockage and poor external ventilation can and should be avoided.
If the ambient temperature of the room air drawn into the chassis is higher than desirable, the air temperature inside the chassis may also be too high. This condition can occur when the wiring closet or rack in which the chassis is mounted is not ventilated properly, when the exhaust of one chassis (or other electronic device) is directed so that it enters the air intake vent of the chassis, or when the chassis is the top unit in an unventilated rack. Any of these conditions can inhibit air flow and induce a shutdown by the CSC-ENVM card.
The chassis can be used as a tabletop or rack-mounted system in a data processing or lab environment. Because the large cooling fan in the chassis is somewhat noisy (approximately
60 decibels, A weighted [dBa]), the chassis is intended for unattended or computer room use.
Table 2-1 lists the air temperature and voltage warning thresholds for the chassis, and Table 2-2 lists the environmental specifications.
Depending upon the temperature and cooling capability of your site, the chassis will require at least a minimum amount of clearance (approximately 2 to 4 inches in an enclosed rack or closet) on all sides to prevent the chassis from taking in the heated exhaust air of other equipment.
| Description | Minimum | Maximum |
|---|---|---|
| Ambient temperature, operating | 32°F (0°C) | 104°F (40°C) |
| Ambient temperature, nonoperating | -40°F (-40°C) | 185°F (85°C) |
| Ambient humidity, operating | 5% RH1 | 95% RH |
| Ambient humidity, nonoperating | 5% RH | 95% RH |
| Altitude, operating | -500' (-152 m) | 10,000' (3,050 m) |
| Altitude, nonoperating | -1,000' (-304 m) | 30,000' (9,144 m) |
| Vibration, operating | - | 5-500 Hz, 0.5G (0.1 oct./min.) |
| Vibration, nonoperating | - - - | 5-100 Hz, 1G (0.1 oct./min.) 100-500 Hz, 1.5G (0.2 oct./min.) 500-1,000 Hz, 1.5G (0.2 oct./min.) |
The proper placement of the chassis and the layout of your equipment rack or wiring closet are essential for successful system operation. Equipment placed too close together and inadequately ventilated can cause system malfunctions and shutdowns. In addition, chassis front panels made inaccessible by poor equipment placement can make system maintenance difficult.
Read and follow these precautions when planning your site layout and equipment locations; this will help avoid future equipment failures and reduce the likelihood of environmentally caused shutdowns.
Use the Installation Checklist following to assist you with your installation, by allowing you to keep track of what was done, by whom, and when. Make a copy of this checklist and make entries as each procedure is completed. Include a copy of the checklist for each system in your Site Log along with your records for the router. (See the section "Site Log" on page 2-7.)
for site
__________________________________________________________________
| Task | Verified by | Date |
|---|---|---|
| Chassis received | ||
| Chassis system unpacked | ||
| Chassis components verified | ||
| Read "Safety Recommendations" section on page 2-1 | ||
| Installation Checklist copied | ||
| Site Log established and background information entered | ||
| Site power voltages verified | ||
| Site environmental specifications verified | ||
| Required tools available | ||
| Network connection equipment available | ||
| Chassis mounted in rack (optional) | ||
| Chassis connected to AC source | ||
| Network interface cables and devices connected | ||
| ASCII terminal attached to console port | ||
| Console port set for 9600 baud, 8 data bits, 2 stop bits, no parity | ||
| System boot complete (all Normal LEDs lit) |
Router name: ________________________________
Router serial number: _________________________________
The Site Log provides a historical record of all actions relevant to the router system. Keep the Site Log in a common place near the chassis where anyone who performs tasks has access to it. Site Log entries might include the following:
Following are the tools and equipment required to attach the rack-mount kit and install the chassis:
When setting up your system, you must consider a number of factors related to the cabling required for your console terminal connections. Each of these cabling considerations is described in the following sections.
A variety of similar signaling schemes use the name RS-232. The following scheme, which is used in all modular and fixed-configuration products, is sufficient to control most modems and hardware flow-control schemes. This scheme provides six signals per line, two of them outputs:
The line drivers are supplied with bipolar 12 volt (V) power; an open output signal will be near +12 or -12V. The Receive Data input has a 10,000 ohm resistor to the -12V supply that helps prevent open lines from ringing and causing spurious input to the communication server. An open Receive Data line will be near -7V, but can vary from -6 to -10V depending on temperature and component variation.
The length of your networks and the distance between connections depends on the type of signal, the signal speed, and the transmission media (the type of cable used to transmit the signals). For example, standard coaxial cable has a greater channel capacity than twisted-pair cabling. The distance and rate limits in these descriptions are the IEEE recommended maximum speeds and distances for signaling. You can usually get good results at speeds and distances far greater than these; however, the maximum distances are not recommended.
For instance, the recommended maximum rate for V.35 is 2 megabits per second (Mbps), but is commonly used at 4 Mbps without any problems. If you understand the electrical problems that might arise and can compensate for them, you should get good results with rates and distances greater than those shown here; however, do so at your own risk.
The following distance limits are provided as guidelines for planning your network connections before installation.
The distance limitations for single-mode and multimode Fiber Distributed Data Interface (FDDI) stations are listed in Table 2-3. Both FDDI modes provide 11 decibels (dB) of optical power.
| Transceiver Type | Max. Distance Between Stations |
|---|---|
| Single-mode | Up to 6.2 mi (10 km) |
| Multimode | Up to 1.2 mi (1.9 km) |
The maximum distances for Ethernet network segments and connections depend on the type of transmission cable used. The unshielded twisted-pair (UTP) cabling used with 10BaseT is suitable for voice transmission, but may incur problems at 10-Mbps data rates. UTP cabling does not require the fixed spacing between connections that is necessary with the coax-type connections. Table 2-4 lists the IEEE recommendations for the maximum distances between 10BaseT station (connection) and hub.
| Transmission Speed | Max. Station-to-Hub Distance |
|---|---|
| 10 Mbps (10BaseT) | 328' (100 m) |
As with all signaling systems, serial signals can travel a limited distance at any given rate. Generally, the lower the baud rate, the greater the distance. Table 2-5 lists the standard relationship between baud rate and distance for RS-232 signals.
| Baud Rate | Distance (Feet) | Distance (Meters) |
|---|---|---|
| 2400 | 200 | 60 |
| 4800 | 100 | 30 |
| 9600 | 50 | 15 |
| 19200 | 25 | 7.6 |
| 38400 | 12 | 3.7 |
| 56000 | 8.6 | 2.6 |
Balanced drivers allow RS-449 signals to travel greater distances than RS-232. Table 2-6 lists the standard relationship between baud rate and distance for RS-449 signals.
| Baud Rate | Distance (Feet) | Distance (Meters) |
|---|---|---|
| 2400 | 4100 | 1250 |
| 4800 | 2050 | 625 |
| 9600 | 1025 | 312 |
| 19200 | 513 | 156 |
| 38400 | 256 | 78 |
| 56000 | 102 | 31 |
| T1 | 50 | 15 |
The distance limits for RS-449 (listed in Table 2-6), which are also valid for V.35 and X.21, are recommended maximum distances. You can get good results at distances and rates far greater than these. In common practice, RS-449 supports 2-Mbps rates, and V.35 supports 4 Mbps without any problems; however, exceeding these maximum distances is not recommended.
When wires are run for any significant distance in an electromagnetic field, interference can occur between the field and the signals on the wires. This fact has two implications for the construction of terminal plant wiring:
If you use unshielded twisted-pair (UTP) cables in your plant wiring with a good distribution of grounding conductors, the plant wiring is unlikely to emit radio interference. When exceeding the distances listed in Table 2-4, use a high-quality twisted-pair cable with one ground conductor for each data signal.
If wires exceed recommended distances or pass between buildings, give special consideration to the effect of lightning strikes in your vicinity. The electromagnetic pulse (EMP) 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.
Most data centers cannot resolve the infrequent but potentially catastrophic problems just described without pulse meters and other special equipment. These problems can cost a great deal of time to identify and resolve, so take precautions to avoid these problems by providing a properly grounded and shielded environment, with special attention to issues of electrical surge suppression.
The AGS+ meets FCC part 15B Class A requirements and Verband Deutscher Electrotechniker (VDE) 0871 Limit B levels. All external cables used with the AGS+ need to be constructed with the following requirements:
As an example, the cable should be of equivalent construction to Hitachi Part Number HCM
You must adjust the baud rate of your terminal to match the console and auxiliary port default baud rate of 9600, 8 data bits, no parity, and 2 stop bits. Consult your terminal's documentation for this wiring specification. The console port is a data communications equipment (DCE) device, and the auxiliary port is a data terminal equipment (DTE) device. If necessary, refer to Appendix A, "Cabling Specifications," for the console and auxiliary port wiring scheme required to connect the router to a console terminal or to build your own cables.
Your installation needs depend on many factors, including the interfaces you plan to use. You may need some of the following data communication equipment to complete your installation:
| Warning If the voltage indicated on the chassis label is different from the power outlet voltage, do not connect the chassis to that receptacle. A voltage mismatch can cause equipment damage and may pose a fire hazard. |
Table 2-7 lists all of the components that are included with the shipment of chassis or that are available as options.
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