Alpha Technologies Serial System Controller User Manual

Page 10

018-332-C0-002 Rev. B

1. System Overview

1.1.2 System Self-Test

System self-test is either initiated by expiration of the Auto Test Countdown timer, or

by asserting the Self-Test switch via the digital transponder interface.

Prior to the test sequence, the SSC will:

Verify that all XM2s are operating in line mode

Check the battery capacity and number of strings

Query the XM2 General Status alarms

The test will not run if:

Any power supply is in standby mode when the self-test begins

Either the battery capacity or number of strings has been programmed

to zero

Any power supply alarm is active

After the above conditions have been met, the SSC will begin the test sequence.

During the test, the SSC will:

Disable all battery chargers

Initiate a self-test in a single power supply

Note: Each XM2 auto-test runs to completion before the SSC requests self-

test of the next power supply. Each XM2 in the system is cycled

through its test sequence. If any XM2 reports self-test failure, the

device address of that unit will be reported in the SSC Test Failed

alarm.

Checks to see if a generator is installed in the system (when switch #3

is in the ON position)

Asks the SSC to run a self-test of the engine generator (when switch

#3 is in the ON position)

Turns all battery chargers back on

Test duration is programmed into each XM2 by the SSC. When the Auto-Test Interval

in the master XM2 is reprogrammed, the new value will be detected by the SSC,

which in turn will reprogram all other XM2s in the system.

1.1 Theory of Operation, continued