Symmetricom 5071A, Operating And Programming Manual

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Preface
Operating and Programming Manual xxi
Event Log: The event log automatically stores significant events such as
power supply changes, system warnings, and error messages. The event
log has the following features:
• Non-volatile memory: all data remains if power is lost,
• Stores 190 events,
• Each logged event is time-and-date tagged, and the
• Log may be read locally or via the RS-232C port.
Power input and management: The 5071A operates from either ac- or dc-
power. An internal-standby battery provides at least 45 minutes of
operating power (48V option does not have internal-standby battery).
Power-source priority is controlled by the 5071A. The priority order is:
1. AC-line power: when below the specified minimum voltage or if
absent, the 5071A switches to,
2. External-dc power: if this fails or goes below 22 Vdc, the 5071A
switches to,
3. Internal-Standby battery power.
For 48V option the priority order is:
1. External-dc power: when below the specified minimum voltage
(40Vdc on both dc inputs), or when absent, the 5071A switches to,
2. Ac line power.
(There is no battery backup for 48V option).
Remote Operation: The 5071A may be operated completely via remote
control. The RS-232C port on the rear panel allows the 5071A to be
connected to a printer, a computer, or a data terminal. Using a modem and a
telephone line, the 5071A can be connected to these devices anywhere in the
world. The 5071A is programmed in a standard language called SCPI
(Standard Commands for Programmable Instruments) based on IEEE 488.2.
Status Output: The rear-panel status port gives you an additional option
for remote monitoring of the 5071A‘s operating status. In its default mode
the rear-panel Status Output indicates when the Continuous Operation
light goes out. You can re-program this output to activate on other
combinations of internal events.
The Status Output is TTL with the active state asserted LOW. The
status outputs of several 5071A’s can be connected in parallel (in a
wired-OR configuration) to operate a system monitor, or act as a
service-request signal for a computer. See Rear-Panel Status Output
Operation in Chapter 5 for details.