Chapter 10 BCU operation and communication status
120 BMTX-SVN01C-EN
BCU reset procedures
If the seven-segment LED display sequence does not follow the startup
sequence, it may indicate a failure of the BCU. Depending on the failure
mode and the status displayed in the seven-segment LED display (see
Table 29 on page 118), you may need to reset the BCU. There are four lev-
els of reset for the BCU. In order of least to greatest impact on the BCU,
the reset levels are:
1. Reset
2. Clear BCU RAM and Reset
3. Clear Database, RAM, and Reset
4. Clear Code, Database, RAM, and Reset
For detailed information about reset levels, see Table 30 on page 123.
The reset procedures are typically done by selecting BCU Reset/Restore
from the Tools menu in Tracer Summit. All of the “Clear . . . Reset” proce-
dures can also be done at the BCU as described in the following subsec-
tions.
Reset
To reset, cycle power to the BCU by unplugging and re-plugging the
24 Vac power connector at the top of the termination board.
Clear BCU RAM and reset
The BCU normally preserves the content of RAM through power failure.
RAM contains the current status of all BCU object trend data, events, and
alarms. In most cases, this is desirable. However, there are circumstances
in which you may need to clear RAM. This is normally done from the PC
Workstation, as described in the Tracer Summit System Programming
guide. RAM can also be cleared at the BCU as follows:
1. Turn off power to the BCU.
2. Set all DIP switches to on.
3. Turn on power.
4. The LED display should show 8, then 7, and then E with the decimal
point flashing.
CAUTION
If you wait longer than 10 seconds, the BCU code and database may be
cleared as well as its RAM.
5. As soon as the LED display shows E with the decimal point flashing,
turn off power.
6. Set the DIP switch to its proper position.
7. Turn on power. The LED display should show the following sequence:
8, 7, 6, 4, 3, 2, H, –, “dancing dash”
To Next Page
Loading...
Need help?
General
