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5.10 Digital Control: Transfer Function PWM Input
The transfer function PWM input is the relation between the Drive speed and the duty cycle on the pin
digital PWM input / active low: PWM* / E*.
It is called ”positive logic duty cycle definition”.
Considering this definition, - continuous low voltage is 0 % duty cycle (dominant level)
- continuous high voltage is 100 % duty cycle (recessive level)
Based on this duty cycle definition the transfer function PWM input is shown in the following figure.
5.11 Drive Speed Set Point with Digital Control
5.12 Analog Control: Transfer Function Analog Input
5.13 Drive Mode - Failure Modes
The PWM signal on the control input PWM* / E* is measured by the Drive electronics. For improving noise to signal
ratio the PWM signal becomes only valid and is only used to set the speed of the Drive when a sufficient number of
consecutive duty cycle measurements are equal.
This plausibility test slightly delays the response to the change of the duty cycle PWM value.
This delay is in the range of 0.2 s or less.
The transfer function analog input is the relation between the Drive speed and the duty cycle on the pin
analog input A (see following figure).
Failure Mode
Handling of Failure
Notification
Drive blocked
In case of detection of a rotor locked the following strategy is used:
a delay of 5 s till the next start attempt is introduced. If this start
attempt fails again a delay increased by further 5 s till the next start
attempt is introduced. This delay increase is repeated till the delay
between the attempts is 25 s. Then this delay is kept for ever as
long a valid PWM duty cycle is detected which asks the Drive to run
Notification is
not available as
no feedback is
provided to the
CCU.
Drive overloaded
Fan speed is reduced in case of overload detection by means of
current draw measurement.
Over current
The Drive will stop if the over current safety threshold is reached.
Drive overheated
Fan speed is reduced in case of overheating detection (derating).
Over the max operating temperature, the Drive will stop.
Under / Over voltage
If the supply voltage is outside the specified range the Drive will
stop.
Internal Drive Failure
The Drive will stop if a failure is detected during the startup self
check procedure.
In all cases the Drive tries to recover from failures when a valid PWM signal is detected which asks the Drive
to run.
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Parker Hannifin
Cylinder and Accumulator
Division Europe
Parker Hannifin
Cylinder and Accumulator
Division Europe
Manual and Installation Guide
Manual and Installation Guide
QDC
for electrified mobile applications
QDC
for electrified mobile applications