通用汽车的voltage drop测试

aitaitait

  请问有没有高人了解通用汽车的voltage drop测试？下面是GM标准的原文，请指点，谢谢！

4.1.1 Voltage Drop. Voltage drop is a measure of
the power and associated temperature rise a circuit
is generating as it passes current. Voltage drop measurements
conducted across contacts which have remained
open for sustained periods will be higher than
measurements taken after one or two cycles of operation.
For this reason, start the voltage drop test by
measuring contact interfaces which require actuation;
then return to the contacts which make circuit in the
de-energized state.
4.1.1.1 Apply the nominal test specification operating
parameter (temperature, pressure, displacement,
etc.) which causes an eiectrical circuit change of state
to occur. Maintain the operating parameter until electrical
or mechanical stability is achieved.
4.1.1.2 A Kelvin or four-wire approach shall be used
to assure the connector interface is not part of the
recorded measurement. When a Kelvin approach is
not practical due to device design, such as in the case
of skirted or sealed switches, voitage drop shall be
determined by placing the voltmeter probes on the
female connectors or at a point on the harness 75 mm
from the connector interface. Note any non-Kelvin
method on the test data sheet.
4.1.1.3 Use an analog or digital voltmeter capable of
0.001 volt resolution and apply the rated resistive load
as defined by the test specification. Refer to the circuit
schematic for terminal identification; then check all
contact interfaces for all normally open and normally
closed circuits.
4.1.1.4 Take the voltage drop measurements
0.5 to 3.0 s after the load current has stabilized. If
reading is out of specification limits, repeat measurements
three times while switching the rated load
and average readings to assure the value will be
repeatable when returned to the design source. If the
switch load current is pulsing or intermittent, test at a
steady state resistive load equal to the steady state
application load.

diegozhao

标准已经说的十分清楚了。。 [s:23]