Rockwell Automation SB3000 Universal Drive Controller Module - Manual (Page 13)

Mechanical/Electrical Description 2-1
C
HAPTER
2
Mechanical/Electrical Description
The following is a description of the faceplate LEDs, connectors, switches, and the
electrical characteristics of the module.
2.1 Mechanical Description
The UDC module is a printed circuit board assembly that plugs into the backplane of
an AutoMax rack. It consists of a printed circuit board, a faceplate, and a protective
enclosure. The faceplate contains tabs at the top and bottom to simplify removing the
module from the rack. The back of the module contains two edge connectors that
attach to the rack backplane. Module dimensions are listed in Appendix A. See figure
2.1 for the module faceplate. (Note that, except for the B/M number designation, the
UDC module faceplates are identical.)
The faceplate contains six status and fault LEDs for diagnostic purposes. These are
described in detail in section 2.2.1. Ports are provided for two sets of fiber-optic cables
which provide the connections between the UDC module and the PMI(s). The UDC
module is shipped with dust caps covering the fiber optic connectors. To prevent
damage to the connectors, the dust caps should not be removed until you are ready to
connect the fiber-optic cables (see section 3.2), and should be replaced whenever the
cables are disconnected from the UDC module. The UDC module has four analog
output ports which can be connected to meters or chart recorders (see section 2.2.4).
Any register in the UDC dual port memory can be mapped to these ports for output to
a meter or data-logging device. A switch and push-button located on the faceplate can
be used for test purposes (see section 2.2.5).
2.2 Electrical Description
The UDC module is designed to work in an AutoMax rack as a Multibus slave only. It is
not capable of acquiring the bus to read or write data to an I/O module.
The UDC module uses a 32-bit RISC (Reduced Instruction Set Computer)
microprocessor running at 20 MHz. (The UDC EM also contains cache memory on the
microprocessor, allowing UDC tasks to execute faster.) The module also contains a
local watchdog timer which must be written to by internal software every 9
milliseconds. If a watchdog time-out occurs, the Card OK LED on the module
faceplate will turn off. The module can generate interrupts to an AutoMax application
task based on a user-defined time period for the purpose of synchronizing multiple
drives.
Two separate fiber-optic links are used to provide high-speed serial communication
between the UDC module and the PMIs. The fiber-optic links transmit
Manchester-encoded data at a rate of 10 Mbit/sec. using cyclical redundancy (CRC)
error checking. The links are used to load the PMI operating system to the PMI and to
transmit/receive reference and feedback data. See section 2.2.3 for a description of
the communication cycle between the UDC module and the PMI.