Arbiter Systems 1088A, Operation Manual

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C.14 Option 18: IRIG-B BUS Distribution, Fault Monitor and 2nd RS-232 Port 151
C.14 Option 18: IRIG-B BUS Distribution, Fault Monitor and
2nd RS-232 Port
C.14.1 General Description
Option 18 for the Model 1088B adds several capabilities to the clock, which are often used in
systems applications. These capabilities include:
•
An IRIG-B distribution bus amplifier that drives dozens of loads over distances of hundreds
of meters
•
A fault monitor that expands the ability of the Model 1088B to detect internal faults and
provides two form-C (SPDT) fail-safe relay contact sets to indicate the Unlocked and Fault
conditions. These relay contacts are for connection to external equipment such as a digital
fault recorder.
•
A second serial (RS-232) port, which can be used as a status event logger, for a broadcast
time output, to connect to a second computer; or as a redundant clock interface allowing two
Model 1088B clocks to be interconnected to form a redundant timing system.
C.14.2 Specifications
IRIG-B Distribution Bus
Output Connector: Pluggable terminal strip, 5mm centers.
Loads 24, minimum, with Model 10882A load taps.
Bus Length Limited by bus configuration; will drive 500m (1500’) of
AWG18 twisted-pair cable in a linear configuration.
Delay Less than 100 microseconds, typical; depends on loading and
bus configuration.
Output Level, Tap Output 6.4-11 Vpp, open-circuit; 3.2-5.5 Vpp, into 600 ohm load.
Fault Monitor
Indication: Via rear-panel relay, front-panel display, or serial port.
Faults Detected:
IRIG-B Distribution: Three fault modes will generate an alarm: any break in the
distribution bus; or a short circuit, or load impedance below
50 ohms; or any loss of the IRIG-B drive signal.
Processor: Watchdog violation or other reset condition.
Power Supply: 5 volt, +12 volt and -12 volt supplies out of limits.