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1257 User Manual
EADS North America Defense
Introduction 1-7
Test and Services, Inc.
©
2001
•
External Trigger Input.
Allows an external device to
trigger switching operations. The external device connects
to the
External Trigger In
connector.
•
External Trigger Output.
Provides a pulse on the
External Trigger Out
connector to trigger an external
device, such as a DMM, after the relay states have
changed.
•
Scan Lists.
Allows you to specify a sequence of relay
closures to step through in response to an external trigger
source. A scan list may include relays on one module or
multiple modules.
•
Programmable Delay.
Allows you to specify the amount
of time delay from a relay state change to an external
trigger pulse.
•
Verification.
Allows you to verify the status of all switches.
•
Path-Level Switching.
Allows complex paths to be
defined with open and close elements, stored in non-
volatile memory, and be controlled remotely or through the
front-panel display.
•
Confidence Mode.
Automatically verifies correct
application of voltage to relay coils.
•
Non-Volatile Memory.
Stores and recalls switch
configurations and 1257 user preferences (such as GPIB
address and RS-232 baud rate).
•
Power-Up Recall.
Automatically recalls a complete
switching system configuration from non-volatile memory at
power-up.
•
Self-Test.
Ensures that critical system components are
functioning correctly. This test executes automatically at
power-up.