Meet Type I
or Type II requirements and test methods for a deceleration alert system.
(i) Type I - the system must:
(A) Be mounted on the rear of the vehicle as
close as possible to the vertical centerline of the vehicle.
(B)Be mounted at a height of not more than
seventy-two inches nor less than fifteen inches.
(C) Have a center-to-center (optical axis)
distance between two adjacent compartments not exceeding six inches.
(D)Have three compartments. The center
compartment emits a green light and is energized when the vehicle operator has
the accelerator depressed. The two outer compartments emit an amber light and
are energized when the operator releases the accelerator and prior to applying
pressure to the foot brake pedal. When the amber lights are energized, the
green light is deenergized. When pressure is applied to the foot brake pedal,
the amber lights are deenergized and the vehicle's stop lamps operate in the
normal manner. SAE Standard J578d is adopted for color chromaticity
boundaries.
(E)Meet the
requirements under the following sections of SAE J575g: Section B, samples for
test; Section C, lamp bulbs; Section D, laboratory facilities; Section E,
vibration test; Section F, moisture test; Section G, dust test; Section H,
corrosion test; and Section J, photometry. If plastic material is used in
optical parts it must comply with the requirements set forth in SAE
J576c.
(F)Measure the beam candle
power with the H-V axis taken as paralleled to the longitudinal axis of the
vehicle. The candle power measurements for the center green compartment must be
made with the incandescent filament of the lamp at least ten feet from the
photometric screen.
Beam candle power measurements of the two amber compartments
must be made by either of the following methods:
(I) The two compartments may be photometered
together provided that a line from the optical axis (filament centers) of each
compartment to the center of the photometer sensing device does not make an
angle of more than 0.6° with the photometer (H-V) axis.
(II)Each compartment may be photometered
separately by aligning its axis with the photometer and adding the value at
each test point.
Table 1 lists the design candle power requirements for the two
outer amber lights, and Table 2 lists the design candle power requirements for
the center green light.
Table 1
Minimum Design Candle power Requirements for
Amber Light |
Test |
Points |
Candle power |
10 up |
10L |
25 |
and |
V |
65 |
10 down |
10R |
25 |
|
20L |
25 |
|
10L |
65 |
5 up |
5L |
85 |
and |
V |
125 |
5 down |
5R |
85 |
|
10R |
65 |
|
20R |
25 |
|
20L |
25 |
|
10L |
75 |
|
5L |
125 |
|
H-V |
175 |
|
5R |
125 |
|
10R |
75 |
|
20R |
25 |
|
Maximum |
450 |
Table 2
Minimum Design Candle power Requirements for
Green Light |
Test |
Points |
Candle power |
10 up |
10L |
1 |
and |
V |
1.5 |
10 down |
10R |
1 |
|
20L |
1 |
|
10L |
2 |
5 up |
5L |
4 |
and |
V |
4 |
5 down |
5R |
4 |
|
10R |
2 |
|
20R |
1 |
|
20L |
2 |
|
10L |
3 |
|
5L |
5 |
|
H-V |
5 |
|
5R |
5 |
|
10R |
3 |
|
20R |
2 |
|
Maximum |
45 |
(ii) Type II - The system must:
(A)Operate so as to indicate a component of
deceleration of the vehicle on which it is installed by varying the flashing
rate of a yellow lamp when the service brakes are applied.
(B) Incorporate an automatic means for
reducing the intensity of the lamp during darkness. The system must cause the
voltage to the deceleration lamps to decrease to 5.0 V ± 10% at 0 g
deceleration during darkness. The specified voltage must be reached when the
illumination on the sensor is not more than 5 lm/sq. ft., nor less than 0.5
lm/sq. ft.
(C)Have an output
voltage, duty cycle, and flash rate of the control unit as a temperature of
24°
± 5.5°C (75°
± 10°F), when 12.8 V dc is
applied to the input terminal, as shown in Table I when the control sensor is
placed on a tilt table and slightly vibrated as the table is slowly rotated
through the angles representing the specified vehicle deceleration rates.
TABLE I
Test Requirements for Deceleration Lamps
Deceleration (g) |
Output (V) |
Peak Relative Brightness |
Flash Rate (Hz) |
On Time (%) |
0.0 |
7.0 |
1.0 |
1.0 |
50 |
0.1 |
__ |
1.0 |
1.5 |
48 |
0.2 |
__ |
1.0 |
2.3 |
46 |
0.3 |
__ |
1.2 |
3.4 |
44 |
0.4 |
__ |
1.4 |
5.0 |
42 |
0.5 |
__ |
1.7 |
7.6 |
40 |
(D)
Have a deceleration at which the unit switches from a lower to a higher flash
rate that is within ± 0.05 g of the rate specified in Table I. If the
unit operates at more steps than the required minimum, the additional values
for each column must lie on the smooth curve connecting the indicated values
within the specified tolerances. The values specified in Table II apply to
ramp-type inertial sensors for which the downward angles correspond to the
deceleration and a tolerance of 3.0° applies to the tilt angle.
TABLE II
Test Requirements for Deceleration Sensors
DEGREES |
Deceleration (g) |
Forward Tilt Angle |
Dip Correction |
Corrected Tilt Angle |
0.0 |
0.0 |
0.0 |
0.0 |
0.1 |
5.7 |
0.8 |
6.5 |
0.2 |
11.3 |
1.6 |
12.9 |
0.3 |
16.7 |
2.4 |
19.1 |
0.4 |
21.8 |
3.2 |
25.0 |
0.5 |
26.6 |
4.0 |
30.6 |
(E)Have
the rms of the output voltage during the on portion of the flash cycle at the 1
Hz flash rate within ± 5% of the specified value, measured at the lamp
bulbs with daytime illumination on the automatic darkness sensor.
(F)Have a relative brightness of the lamp or
bulbs at the decelerations within ± 25% of the specified values after
the fifth flash with the brightness of the lamp or its bulbs taken as 1.0 when
measured with the rms output voltage specified for 0 g deceleration.
(G) Have a flash rate within ± 15% of
the specified value. The percent on time must be within ± 10% of the
specified value.
(H) Have linear
dip corrections varying from 4° at 0.5 g or more deceleration to 0° at
0 g on passenger vehicles and pickup trucks that have substantial front end dip
upon braking.
(I) Comply with the
following mechanical tests in SAE Standard J575g (tests for motor vehicle
lighting devices and components): Corrosion, dust, moisture, vibration, and
warp-age (at a flashing rate of 1 Hz when a plastic lens or housing is
used).
(J) Meet the following
control system requirements at both 11 V and 15 V:
(I) Low temperature test. The control system
must be placed in its normal operating position in a circulating air cabinet at
-32°
± 3°C (-25°
± 5°F) for 2 hours. At the end
of that period and while still at that temperature, the unit must meet the
requirements in Table I at 0 g and 0.3 g.
(II)High temperature test. The control system
must be placed in its normal operating position in a circulating air cabinet at
74° 0°, -2.8°C (165° 0°, -5°F) for 2 hours. At the end
of that period and while at that temperature, the unit must meet the
requirements in Table I at 0 g and 0.3 g.
(K) Operate the control system continuously
at a supply voltage of 12.8 V dc for 200 hours with no failure (except bulb
replacement), after which it must meet the requirements in Table I at 0 g and
0.3 g.
(L) Meet the photometric
requirements in Table III after the sample has been mechanically tested in the
order shown in (b)(ii)(J) of this subsection for the luminous intensity of a
deceleration lamp with the bulbs operated at mean spherical candela.
TABLE III
Photometric Requirements for Deceleration Signal Lamps
Test Point Coordinates |
Max |
Cd |
Min |
Vertical |
Horizontal |
Amber |
Red |
Amber |
Red |
|
10L |
70 |
35 |
25 |
12.5 |
10U |
V |
200 |
100 |
60 |
30 |
|
10R |
70 |
35 |
25 |
12.5 |
|
20L |
40 |
20 |
15 |
7.5 |
|
10L |
200 |
100 |
60 |
30 |
|
5L |
600 |
300 |
200 |
100 |
5U |
V |
800 |
400 |
350 |
175 |
|
5R |
600 |
300 |
200 |
100 |
|
10R |
200 |
100 |
60 |
30 |
|
20R |
40 |
20 |
15 |
7.5 |
|
20L |
40 |
20 |
15 |
7.5 |
|
10L |
200 |
100 |
60 |
30 |
|
5L |
800 |
400 |
350 |
175 |
H |
V |
1,300 |
650 |
600 |
300 |
|
5R |
800 |
400 |
350 |
175 |
|
10R |
200 |
100 |
60 |
30 |
|
20R |
40 |
20 |
15 |
7.5 |
|
20L |
40 |
20 |
15 |
7.5 |
|
10L |
200 |
200 |
60 |
30 |
|
5L |
600 |
300 |
200 |
100 |
5D |
V |
800 |
400 |
350 |
175 |
|
5R |
600 |
300 |
200 |
100 |
|
10R |
200 |
100 |
60 |
30 |
|
20R |
40 |
20 |
15 |
7.5 |
|
10L |
70 |
35 |
25 |
12.5 |
10D |
V |
200 |
100 |
60 |
30 |
|
10R |
70 |
35 |
25 |
12.5 |