Agilent Technologies FieldFox MW N9913A, Service Manual

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5-20 N9927-90003
Theory of Operation FieldFox Analyzer
Grounding and Power
Battery Related Information
Battery Description and Operation
The main battery is an SBS (Smart Battery System) compliant pack of lithium ion cells.
Refer to “Battery Disposal” on page 1-7 for important information about replacing and disposing of this
battery.
The nominal voltage of the battery is 10.8 volts and normally varies from 9 to 12 volts.
The battery has built-in sensors, a processor, and control circuitry. This is referred to as the Smart Battery
circuitry.
The Smart Battery circuitry communicates battery condition and history information digitally via a
digital Smart Batt Bus. The Smart Battery circuitry is read-only.
Both the battery charging circuit and the System Monitor read battery information over the Smart Batt
Bus.
The battery temperature reported by the analyzer is based on a sensor inside the battery. Temperature
information is available over the Smart Batt Bus. The thermistor connection (T) on the battery is not
used.
The Smart Battery circuit may shut down the battery when the temperature is out of the acceptable range
or when the battery charge is too low.
See the “Working with the Lithium-Ion Battery” section of the FieldFox User’s Guide for additional
information on:
• built in charge level gauge
• the battery information screen
• battery care
Battery Information Screen
Refer to the FieldFox User’s Guide for information on how to access this screen.
Most of the items displayed on the screen come directly from the battery via the Smart Batt Bus. Only
the first three items are influenced by the analyzer.