Table of Contents
Advertisement
Operating Basics
Configure the SPG trigger
The SPG trigger input function allows for a condition that is sensed in the
Tektronix SPG8000 and TG8000 generators to trigger a source changeover on
input
the ECO8000 Series unit. For example, if the genlock on the primary SPG8000
generator loses lock, then that SPG8000 can signal the ECO8000 Series unit to
switch to the backup source. Since the SPG8000 and TG8000 generators have
comprehensive internal monitoring capability, this allows the overall system to
react to more subtle sync conditions, sometimes even before they start to cause
problems.
To use this function, the GPI outputs from the primary and backup sync generators
must be connected to the LTC/SPG conectors on the ECO8000 Series. If the
sync generator is a Tektronix SPG8000, or a TG8000 with a GPS7 installed,
the connections can be done using a 15-pin HD DSUB cable. For other sync
generators, a custom wiring harness may be required. See SPG trigger cable
connections below.
The primary and backup SPG8000 or TG8000 generators need to have the GPI1
output programmed to assert on the combination of events which are intended to
cause a changeover trigger. A common set of conditions to enable are "Hardware
Fault," "Near Loss of Lock," and "Lock Error" with a 10 second delay. With these
settings, the SPG will detect these conditions, assert GPI1, and then the ECO will
detect that SPG Trigger input and trigger a changeover.
CAUTION.
If the primary and backup SPG8000 generators use a common
reference, such as the same genlock source or the same GPS antenna, then the
primary SPG8000 generator should be set for a longer delay on loss on lock. In
case of a failure on the common reference, this allows the primary SPG8000
generator to assert the fault later, which avoids an unnecessary source switch by
the ECO8000 Series.
Additionally, the ECO8000 Series may switch sources when the two SPG8000
generators relock if the backup generator locks before the primary generator.
ECO8000 Series Automatic Changeover Unit User Manual
31
Advertisement
Table of Contents
