Setup

TM-XDSL-01XN.book Page 20 Tuesday, November 5, 2002 3:22 PM

Current Sharing

Overview

CANbus The CANbus port is a one male, one female DB9 connector to support “daisy chain” Setup connections. The CAN (Controller Area Network) is an ISO standard (ISO11898) for a serial communication network. Table 3.1 describes the pin functions. Pins 1, 4, 8, and 9 are not used. The CANbus is part of the optional GPIB/CANbus interface

card, which is required for communication between the master unit and its slave units.

Table 3.1 CANbus Pins

Pin #

Function

1Not used

2CANLO

3Ground

4Not used

5Ground

6Ground

7CANHI

8Not used

9Not used

1.Connect power supplies to be controlled via the CANbus network. Parallel male DB9 to female DB9 cables (N-1) are required. Each slave unit is shipped with one male-female DB9 8 in. ribbon cable. Connect the CAN interface cards in series, linking the first power supply to the second using one cable, and then the second to the third using a second cable and the second CAN port. A single ribbon cable with multiple connectors may be used instead of several cables for ease of connection. Terminate the bus at both ends with 120 ohm, 1/4 Watt resistors (included) across the CAN HI and CAN LO signals (Pins 2 and 7). See Table 3.1, “CANbus Pins,” on page 20.

2.The master power supply may be connected to a PC via RS-232 or GPIB.

3.Turn the power supplies on one at a time, starting with the master, and check that the green “Power ON” LED on each slave unit is lit. As each slave is turned on, it will automatically configure itself with a sequential unique address. The address is retained in non-volatile memory.

Note: Only the first 4 slave units powered on will current share.

Note: Only units with the same output ratings will current share.

20	Operating Manual for XDC Series Slave Power Supply