Rockwell Automation AADvance Controller Safety Manual User Manual
Page 125
Document: 553630
ICSTT-RM446K-EN-P Issue: 10
_C
6-9
Chapter 5
Glossary of Terms
termination assembly
A printed circuit board which connects field
wiring to an input or output module. The
circuit includes fuses for field circuits. The
board carries screw terminals to connect
field wiring to the controller, and the whole
assembly clips onto the 9300 I/O base unit.
TMR
Triple modular redundant. A fault tolerant
arrangement in which three systems carry
out a process and their result is processed
by a voting system to produce a single
output.
TÜV certification
Independent third party certification against
a defined range of international standards
including IEC 61508.
U
U
Rack unit. A unit of measure used to
describe the height of equipment intended
for mounting in a standard rack. Equivalent
to 44.45mm (1-¾ inches).
V
validation
In quality assurance, confirmation that the
product does what the user requires.
verification
In quality assurance, confirmation that the
product conforms to the specifications.
voting system
A redundant system (m out of n) which
requires at least m of the n channels to be in
agreement before the system can take
action.
W
withstand voltage
The maximum voltage level that can be
applied between circuits or components
without causing a breakdown.