Digitronic
Digital Cam Switch Unit
Automationsanlagen GmbH
CamCon DC33/X with 8 programs
2.1.1. Measuring delay time for Speed Compensation
Several ways of measuring delay time of a relay or valve are available.
2.1.1.1. Measuring delay time through actual differences
First the switch-ON point of a valve or relay is programmed. We assume that the programmed switch
point lies at 200 degrees in this case. If the machine is driven with a speed of for example 40 rpm, a
shift occurs due to delay time. This shift is then measured and, in this example, will amount to 40
degrees.
Warning:
For the calculation of the shift the programmed delay time in the cam switch unit must be
set to zero!
The delay time of the switch component is now calculated as follows:
Delay time ( in sec. ) =
∆
way (in °) * 60 (sec./min.)
speed (in rpm) * 360 (°/turn)
Delay time ( in sec. ) =
40 * 60
40 * 360
= 0.1667 sec.
The resultant delay time is then entered into the cam switch unit.
See Chapter "6.3. The dead time compensation" an page 15.
2.1.1.2. Measuring delay time by means of different measuring points
First the switch point is calculated at a speed of, for example, 50 rpm. We assume that the
programmed switch point lies at 200° in this case. The second measurement is taken at a speed of 80
rpm The necessary switch point must be set to 160°, if the exact switch point is to be also achieved at
80 rpm.
Warning:
For the calculation of the two switch points the programmed delay time in the cam switch
unit must be set to zero!
The delay time of the switch component is then calculated with the following formula:
Delay time ( in sec. ) =
∆
way (in °) * 60 (sec./min.)
∆
speed (in rpm) * 360 (°/turn)
Delay time ( in sec. ) =
40 * 60
30 * 360
= 0.222 sec.
The resultant delay time is then entered into the cam switch unit.
See Chapter "6.3. The dead time compensation" an page 15.
Since the entered delay time shifts the switch point, the previously programmed cam must be changed.
For the calculation of the exact switch-ON position, the difference to the speed O rpm (here using 50
rpm) must be added to the first measured switch-ON point (here 200°). The difference is calculated
with the following formula:
∆
way (in degrees) =
dead time ( in sec. ) *
∆
time (in min-1) * 360 (degrees/rotations)
60 (sec./min.)
∆
way (in degrees) =
0.222 * 50 * 360
60
= 66.6 degrees
The switch-ON point of the cam is now shifted from 200° by approx. 67° to 267°.
Version from: 18.06.2009
Page: 9
