Rockwell Automation SB3000 Universal Drive Controller Module - Manual (Page 17)

Mechanical/Electrical Description 2-5
The first time the rack is powered up, the UDC module will not contain its operating
system (OS). After the UDC OS is loaded to the UDC module using the AutoMax
Programming Executive software, it will be stored in non-volatile flash memory for
subsequent power-ups.
After passing their own power-up diagnostics, the PMIs will request their operating
systems from the UDC module. The UDC module will download an operating system
to each PMI connected. Each PMI will send a feedback message to the UDC module.
The UDC module will respond with a command message, configuration data, and the
UDC task time base. Subsequent command messages from the UDC module will
contain clock (CCLK) synchronization data so that the PMI can calculate when to send
feedback data to the UDC.
2.2.4 Meter Ports
The module faceplate contains four analog output ports on a single connector labeled
METER PORTS. A 5-point removable plug connector with screw-type terminal points
is used to connect meters or data-logging devices to the UDC module. All connections
are made using 14-22 AWG wire. Terminals 1-4 can each be connected to a separate
analog device. All devices share a single COMMON connector terminal, labeled COM.
The outputs are not isolated from each other. Note that these terminals (1-4 and
COM) must not be connected to earth ground.
Any register in the UDC dual port memory (common) or any local variable can be
mapped to these ports for output to a meter or chart recorder. These devices can be
located up to 4m (13 ft.) from the UDC module. Each port provides 8-bit resolution of
internal data over a -10 VDC to +10 VDC range (78.125 mV/bit). The maximum output
current is 20 mA at +10 VDC. The registers to be output and their minimum and
maximum values are user-configurable. Values are updated each scan of the UDC if
CCLK is on and a UDC task is running. If CCLK is not on, values are updated every
0.20 ms. The analog output ports default to outputting 0 VDC until they are configured
either in an application task or online. See the AutoMax Programming Executive
instruction manual for instructions on how to configure the meter ports. Refer to the
appropriate Configuration and Programming instruction manual for the UDC register
assignments.
.
Figure 2.2 – Analog Output Circuit (Meter Ports)
DATA
10V 20K
–
+
100 Ω
100pf
D/A
20K