PowerLogix COM128 Installation, DC Supply Connections, Directconnection to a Computer

COM128 Installation and Operation Manual

4 INSTALLATION

4.1DC SUPPLY CONNECTIONS

The COM128 is shipped with a 9 VDC adapter which plugs into the adapter receptacle. Use only the adapter provided with the COM128 for this particular powering application.

Alternatively, any DC power supply capable of supplying from 9 to 30 VDC at 500 mA (minimum) can be used to power the COM128. Connect the (+) and (-) outputs from the power supply to the corresponding terminals of the removable 2-pin terminal block connector supplied with the COM128 (See Chapter 2, Figure 2.1.1).

4.2RS-232CONNECTIONS &CONFIGURATION

Sections 4.2.2 and 4.2.3 discuss RS-232 port connections when connecting to a computer or modem. The COM128 configuration switches are used to select which port is active. Note that the COM128 can also be used in other applications by selecting the appropriate port and modes as described in Chapter 3. For configuration switch settings, refer to section 3.2, 'Mode Descriptions'.

4.2.1RS-232 CABLE

A standard RS-232 serial communications cable should be used. The COM128 end must be a female DB9 connector for direct connection, or a male DB25 for connection via the supplied adapter plug. Maximum cable length is 50 feet (15.2 m).

SchneiderElectric

4.2.2DIRECTCONNECTION TO A COMPUTER

PORT SELECTION

An IBM-compatible PC acts as a DTE (Data Terminal Equipment) RS-232 device. Therefore, the computer’s RS-232 port should be connected to the DCE port on the COM128. Refer to Figure 4.2.2.

SWITCH SETTINGS

To properly communicate with the computer, the COM128 must be configured as a DCE (Data Communications Equipment) RS-232 device (see subsection 3.2.1, 'RS-485 Flow Control').

Figure 4.2.2 RS-232 Direct Connection to Computer

RS-232 Cable

50 ft. max.

DCE	RS-232		PORT D
PORT		485-RS
PORT			PORT C
DTE
			PORT B
			PORT A

COM128

RS-232 to RS-485 Converter

SHLD

To

RS-485

Bus

RS-485 Cable

AWG 22 shielded twisted pair. Total length: 4000 ft. maximum.

IBM PC

7