ACES SYSTEMS Cobra II User Manual

Gen II User Manual
23-5 – Equipment and Accessory Setup and Troubleshooting Chapter 23 Revision 4.01, Apr 2020
23.6.1. – Reflective Tape Width Requirements
If problems are experienced using the Phototach (this does not apply to the Lasetach) while
balancing high-speed props with the reflective tape further out on the blade, refer to the
following chart for tape placement adjustments.
 First, measure the distance from the center of the propeller shaft to the location you
intend to place the reflective tape.
 In the chart below, select from the RPM column the first speed greater than the speed at
which you intend to balance.
 From this RPM number, proceed across the chart to the right until you come to the first
number larger than the distance measured in the initial step above.
 From this point, follow the column up to the top to the minimum tape width required for
your application.
As an example, use the following parameters: the distance from the propeller shaft to the
intended tape location measures 25 inches and the balance speed is 2300 RPM. Select
2400 from the RPM column since this is the first speed greater than your intended
balance speed of 2300. From this number, follow the row across to 26.5, which is the first
number higher than your intended tape location of 25 inches. From 26.5 follow the
column straight up to the top–2 inches. This is the width of tape required for accurate
readings at the intended distance and RPM level. (If your reflective tape is only 1-inch
wide, place two 1-inch strips of tape side by side to create 2 inches. Do not leave any gap
between the two pieces of tape, a slight overlap is recommended.)
Minimum Tape Required
RPM
1”
2”
3”
4”
1000
31.8
63.7
95.5
127.3
1
200
26.5
53.1
79.6
106.1
1400
22.7
45.5
68.2
90.9
1600
19.9
39.8
59.7
79.6
1800
17.7
35.4
53.1
70.7
2000
1
5.9
31.8
47.7
63.7
2200
14.5
28.9
43.4
57.9
2400
13.3
26.5
39.8
53.1
2600
12.2
24.5
36.7
49
2800
11.4
22.7
34.1
42.4
23.7. – Vibration Sensor
Do not drop the sensor. Although built for rugged use, most accelerometers and velocity sensors
are susceptible to internal damage when dropped, especially on hard surfaces such as concrete
ramps.
Do not mount a sensor on a hot section of the engine until you are certain it will withstand the
maximum amount of heat being generated in that area. A sensor must be designed for high-

ACES SYSTEMS Cobra II Specifications

General

Brand	ACES SYSTEMS
Model	Cobra II
Category	Measuring Instruments
Language	English