Symmetricom 9611B, Руководство пользователя

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Introduction
Symmetricom’s® 9611B-01 Switch & Distribution Unit is an intelligent switching, monitoring and dis-
tribution system, packaged in a 1U rack mount chassis.
The unit includes a dual input A-B switch that provides redundant capability. The internal micro-
processor can be set up to switch on a number of criteria (i.e., input signal voltage level and period
between detected pulses).
The following figure shows a typical application of the 9611B. Output signals from two XLi instru-
ments are connected to respective A and B inputs of the 9611B instruments for distribution. One sig-
nal is designated as the primary signal and the other as the secondary signal. If the 9611B is in auto
mode, and the primary signal to the 9611B fails, the auto-switch logic recognizes the failure, and
switches to the secondary signal. The secondary signal is now connected to all twelve outputs.
To determine a failure condition, an adjustable threshold voltage or signal timing duration is provided
to the 9611B auto-switching logic. This threshold voltage or signal timing duration is compared with
the selected input signal to the 9611B. When the comparison triggers a fault condition, an alarm is
triggered. The alarm is latched so as not to lose track of it. The alarm will stay latched until the fault
condition has been removed, and the alarm reset has been activated.
As an alternative to the auto-switching mode, either input can be manually connected to the twelve
outputs.
Figure 1: A Typical Application
9611B_UserGuide_RevA.pdf .......................................................................... Page 1