5.2 CABLE PARAMETERS

Data communication cables are used in the CM9760 system to connect required equipment to appropriate data communication ports on the CC1, which are either RS-232 or RS-422 driven.

The characteristics of the cable chosen (if not supplied) depends, first of all, on the driver type it interfaces.

For RS-232 driven ports, such as Com 1 and Com 2, the cable used must meet less stringent communication requirements than that required for driven ports RS-422. The cable for RS-232 communications supports the following driver characteristics:

1.It is single ended – one driver and one receiver.

2.It is unbalanced-a voltage level with respect to system ground drives the commu- nications link.

3.It is limited to low data rates.

4.It is limited to local use: 50 feet or less for synchronized data; 100 to 200 feet for asynchronous data.

For RS-422 driven ports, such as the 32 Sercom ports on the rear of the CC1, the cable chosen by the user must support the following driver characteristics:

1.It is single ended, multi-drop capable.

2.It is balanced-a differential voltage drives the communications link.

3.It handles relatively high data rates. There is a trade off between data rate and cable length (theoretically, up to 4,000 feet [1,220 m] @ 100Kbps) (see Figure 20).

4.It is used for both local and remote hookup of system devices; for example, remote hookup of 9760 keyboards attached to the CC1.

Figure 19: Information Box

BPS or bps means or = bits per second.

Baud = # of signal changes per second.

In the recent past, bps and baud rate were equivalent, that is, 300 bps and 300 baud, for example, were the same.

Two things happened which eventually separated the use of bps and baud as being equal.

1.It became physically possible to transmit more than one bit per signal change through variations in ampli-

tude, frequency, and/or phase.

2.A physical bandwidth limit on voice-grade phone lines made it difficult to reach baud rates greater than 2400.

Most modems do not operate at a speed greater than this.

A modem operating at a Pelco referenced baud rate of 9600 is, most likely, a 2400 baud modem operating at 9600 bps (or a 4:1 compression ratio; 4 x 2400=9600) because of the bps manipulation mentioned above.

Therefore, for higher speed modems and for the graph illus-

trated in Figure 20, modem speeds are listed and referenced

at a bps rate. For convenience, Pelco still refers to modem

 

 

 

 

 

 

 

speeds in all its communication parameter lists by using the

baud rate ( a misnomer), even though the proper reference,

 

 

 

in most cases, is bps. In Figure 20, the

approximate baud

rate range of Pelco equipment is highlighted against the bps

per distance chart.

 

Figure 20. Data Rate vs. Cable Length

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Pelco Manual C539M-A (12/01)

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Pelco CM9760-CXTA operation manual Cable Parameters, Information Box

CM9760-CXTA specifications

The Pelco CM9760-CXTA is an advanced video management and control system designed for professional surveillance applications. It serves as a central hub for monitoring multiple video feeds, providing users with a high degree of control and flexibility. This versatility is critical for industries such as transportation, banking, and public safety, where real-time monitoring and rapid response are essential.

One of the standout features of the CM9760-CXTA is its integration capability. The system supports a range of communication protocols, allowing it to work seamlessly with various Pelco cameras, recorders, and third-party equipment. This interoperability ensures that users can build a customized surveillance solution that meets their specific needs.

The CM9760-CXTA boasts advanced video processing capabilities. It features high-resolution video outputs that ensure clear and crisp images, even in challenging lighting conditions. The system also supports multiple video formats, providing flexibility for various deployment scenarios. The ability to manage multiple camera feeds simultaneously is a vital aspect of this system, enabling operators to switch between cameras and monitor events in real time.

Another key characteristic of the CM9760-CXTA is its robust control capabilities. With support for keyboard and joystick control, operators can easily navigate and manipulate video feeds, adjust camera angles, and set presets for quick access to critical views. This ease of use is complemented by an intuitive user interface, which simplifies the monitoring process and enhances operator efficiency.

The system also excels in its scalability. Whether for a small installation or a large-scale surveillance operation, the CM9760-CXTA can accommodate varying system sizes by adding modules and expanding capabilities as needed. This adaptability is crucial for organizations that anticipate growth or changes in monitoring requirements over time.

In terms of security features, the CM9760-CXTA includes encrypted data transmission and user authentication processes to protect sensitive information. These security measures ensure that only authorized personnel can access critical surveillance data, enhancing the overall integrity of the system.

In summary, the Pelco CM9760-CXTA is a powerful video management system that offers a combination of advanced video processing, robust control features, and scalability. Its ability to integrate with various devices and maintain high security makes it an ideal choice for organizations seeking a reliable and versatile surveillance solution.