Data Flow Systems TCU800, Installation And Operation Manual

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C h a p t e r 4
Auxiliary Analog Input
The TCU’s secondary analog input can be used as a backup to the primary analog level transducer or can be used for a
general purpose analog input (for example, a flow transducer). For more information on using analog input 2 as a backup
to the primary transducer, see “Transducer Fault Mode” on page 52.
It is important to note that analog input 2 supports 4-20 mA only; 0-5 V is not supported.
The diagram on the next page presents a simplified wiring example. Refer to the diagrams in the previous section for
information on using the auxiliary analog input in different applications – for example, when using the TCU as the power
source for the device.
Auxiliary Analog Input
Optional Configurations and Hookups
Backup Battery
Two optional backup batteries are available for use with the TCU. Although a backup battery is not necessary for operation
of the TCU, it is recommended to prevent telemetry data loss from a power failure. Note that statistical and configuration
data is retained even without a backup battery. The purpose of the battery is to maintain telemetry functions during a power
loss.
Based on intended usage, the selected battery can be one of the following:
• 12 V, 2.6 Ah model – part number DFS-00363-008-02; rated at 12 V, 2.6 Ah
• 12 V, 7.0 Ah model – part number DFS-00363-008-01; rated at 12 V, 7.0 Ah
These batteries are interchangeable and maintenance-free. Connect terminal P1-8 (BAT+) to the positive terminal of the
battery. Connect terminal P1-9 (BAT-) to the negative terminal of the battery. It is important to observe polarity when