Cameron NUFLO 1141C, User Manual

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Scanner 1141 Hardware User Manual
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Figure 5.1—Transmitter test points on the 1141 main board
NVRAM Lithium Battery Voltage
The NVRAM lithium battery must register above 2.0 VDC when using ScanWin version 3.0.0 and
higher with firmware version 4.3.5 and above. When measuring the NVRAM battery voltage with a
voltmeter (this measurement can be performed with the battery in the holder while the Scanner is
operating), the voltage will be 0.3 to 0.7 volts higher than when it is measured by the firmware. The
value read by the Scanner firmware is the actual (backup) voltage applied to the NVRAM and PIC (for
operation as an RTC) and includes the voltage drops from the Schottky diodes that are part of the non-
incendive circuit.
Note that with lithium batteries, the voltage drops off dramatically so there is never much of a “low
voltage” warning. A NVRAM battery voltage above 2.0 VDC indicates the configuration is still backed
up; a voltage of zero means that the battery is dead, not installed, or the jumper is missing.
NVRAM Battery Change Procedure
The following steps outline the procedure for changing the NVRAM / lithium backup battery in the
Scanner 1141. The battery will last between 7 and 10 years under normal usage.
1. Use ScanWin to download all configuration, calibration and historical data from the Scanner
RTU.
2. Turn off the Scanner 1141 RTU by moving the Power switch (SW9) to the “down” or OFF
position.
3. Disconnect the power supply to the Scanner 1141.
4. Lift the clip that holds the lithium backup button cell battery in the upper left-hand corner of the
board and remove the battery. Replace it with a 3.6V lithium button cell battery, noting the
correct polarity.
5. After ensuring that all connections have been made, restore power to the unit following the
startup procedure on page
55 .
6. Restore the configuration to the unit with ScanWin.