Technical information

Norman Wells Fire Department
SVI Emergency Vehicles
NORNWLR-0002 11/02/12
Page 6 of 63
2. ALTERNATOR PERFORMANCE TEST
TEST AT IDLE
The minimum continuous electrical load shall be activated with the engine running at idle speed. The engine
temperature shall be stabilized at normal operating temperature. The battery system shall be tested to detect the
presence of battery discharge current. The detection of battery discharge current shall be considered a test
failure.
TEST AT FULL LOAD
The total continuous electrical load shall be activated with the engine running up to the engine manufacturer’s
governed speed. The test duration shall be a minimum of two (2) hours. Activation of the load management
system shall be permitted during this test.
An alarm sounded by excessive battery discharge, as detected by the warning system required in 13.3.4 or a
system voltage of less than 11.8 V dc for a 12 V nominal system, 23.6 V dc for a 24 V nominal system, or 35.4 V
dc for a 42 V nominal system for more than 120 seconds shall be considered a test failure.
3. LOW VOLTAGE ALARM TEST
The following test shall be started with the engine off and the battery voltage at or above 12 V for a 12 V nominal
system, 24 V for a 24 V nominal system, or 36 V for a 42 V nominal system.
With the engine shut off, the total continuous electrical load shall be activated and shall continue to be applied
until the excessive battery discharge alarm activates. The battery voltage shall be measured at the battery
terminals.
The test shall be considered a failure if the alarm does not sound in less than 140 seconds after the voltage drops
to 11.70 V for a 12 V nominal system, 23.4 V dc for a 24 V nominal system, or 35.1 V for a 42 V nominal system.
The battery system shall then be able to restart the engine. Failure to restart the engine shall be considered a test
failure.