Beckhoff AX2090-BW65, Руководство по сборке

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Electrical installation
Version: 1.0 ─── 29 AX2090-BW65
8.2
Short-term power
Brake resistors are usually not operated continuously, but only ex-
posed to short-time duty. In the following chapter, the short-term
power will be calculated from the following factors:
• Continuous power
• Overload factor
• Duty cycle
8.2.1
Duty cycle
8.2.1
Position Explanation
1 Switch-on time t
on
2 Cycle time
The duty cycle is a relative value and depends on the switch-on time
t
on
and the cycle time. A cycle time of up to 120 seconds is incorpo-
rated directly into the calculation. If the cycle time exceeds 120 sec-
onds, you must use the maximum relevant cycle time of 120 sec-
onds.
Calculation equation
• Duty cycle = t
on
/ Cycle time x 100 %
Example
T
on
= 60 s
Cycle time = 120 s
60 s / 120 s x 100 % = 50 % duty cycle
T
on
= 40 s
Cycle time = 100 s
40 s / 100 s x 100 % = 40 % duty cycle