Functional Scope Of PWM Functions, PSM, Function - GF54.21-D-3010P
MODEL 906 with CODE ED5 (Parameterizable special module (PSM)) with CODE XM0 (Facelift)
MODEL 906 with CODE ED8 (Preinstallation for parameterizable special module (PSM)) with CODE XM0 (Facelift)
Pulse width modulation (PWM) functions (PWM output)
Signal "Tml. 58d (PWM)"
The signal "circuit 58d (PWM)" from the instrument cluster can be output as a PWM signal on the PWM-capable output 09 or output 10.
If no signal is received, 0 % is output.
| Signal-ID 3006 |
|---|
| Value range 0 to 100 % |
| Output frequency 500 Hz |
Signal "Display dimming (PWM)"
The "Display dimming (PWM)" signal from the instrument cluster can be output as a PWM signal at the PWM-capable output 09 or output 10.
If the "Display dimming (PWM)" signal from the instrument cluster is invalid, 70 % is output.
If the "Display dimming (PWM)" signal changes, the new percentage is set using a ramp in order to prevent a sudden change in the display dimming. The parameters can be set via menu item "Interfaces → Interior CAN bus → Miscellaneous → Properties".
There are 2 parameters:
- Time for dimming of instrument illumination:
- Time in 10 ms steps which determines the duration of the ramp.
- Brightness of instrument illumination:
- Change in percent per ramp step
Output of the signal depends on the status of tml. 15R.
With "Tml. 15R ON", the output value is determined by the status of the standing lights. If the standing lights are ON, the previously set value is retained. If the standing lights are OFF, 70 % is set.
| Signal ID301A |
|---|
| Value range 0 to 100 % |
| Output frequency 500 Hz |
Signal "Vehicle speed (PWM)"
The "Vehicle speed (PWM)" signal from the instrument cluster can be output as a PWM signal at the PWM-capable output 09 or output 10.
If no signal is received, no pulses are output.
Output of the signal depends on the state of tml. 15.
With "Tml. 15 OFF", no pulses are output.
The following formula applies for converting the vehicle speed into pulses:
- Pulses (1/s) = [Speed (km/h) X 4 (pulses/m)] ÷ 3.6 The following settings apply:
| Signal-ID 3007 |
|---|
| Value range 4 to 254 km/h (speed) |
| Value range 4.4 to 282.22 pulses/s PWM signal) |
| Pulse steps 4 ms up to 112.5 km/h, then reduced to 1.77 ms |
Signal "motor speed (PWM)"
The signal "motor speed (PWM)" from the EZS control unit can be output as a PWM [pulse width modulation] signal on the PWM-capable output 09 or output 10.
If no signal is received, no pulses are output.
The output of the pulses can be set with the "K-Factor" parameter via menu item "Interfaces - Outputs - Assignment of PWM signals to outputs 09 and 10 - Properties/pre-assigned PWM signals". This parameter determines how many pulses are output per revolution. The default value is one pulse per revolution.
The following formula applies for converting the motor speed into pulses:
- Pulses (1/s) = K-Factor X engine speed (rpm) ÷ 60
The following settings apply:
| Signal-ID 3002 |
|---|
| Value range 1 to 10 (K-Factor) |
| Value range 400 to 12, 000 rpm (engine speed) |
| Value range 6.7 to 2000 pulses/s (PWM signal) |
| Pulse steps fixed at 400 s |
Signal "Interior temperature (PWM)"
The "Interior temperature (PWM)" signal from the air conditioning system can be output as a PWM signal at the PWM-capable output 09 or output 10.
If no signal is received, 0 % is output.
Output of the signal depends on whether the air conditioning system is installed. If no air conditioning system is installed, 100 % is output.
The following formula applies for converting the interior temperature into the percentage (duty cycle) for PWM output:
- Duty cycle = [Interior temperature (°C) X 4] ÷ 232 (°C)
The following settings apply:
| Signal ID300A |
|---|
| Value range 0 to 58 °C (interior temperature) |
| Value range 0 to 100 % (PWM signal) |
| Pulse steps 200 Hz |
Signal "Outside temperature (PWM)"
The "Outside temperature (PWM)" signal from the instrument cluster can be output as a PWM signal at the PWM-capable output 09 or output 10.
If no signal is received, 0 % is output.
The signal output depends on the installation of the outside temperature sensor. If the temperature sensor is not installed, 0 % is output.
The following formula applies for converting the outside temperature into the percentage (duty cycle) for PWM output:
- Duty cycle = [Outside temperature (°C) + 40 (°C)] ÷ 125 (°C)
The following settings apply:
| Signal-ID 3009 |
|---|
| Value range -40 to 85 °C (outside temperature) |
| Value range 0 to 100 % (PWM signal) |
| Pulse steps 200 Hz |
Signal "Wheel speed (PWM)"
The wheel pulse counter can be output as a PWM signal at the PWM-capable output 09 or output 10.
The pulses to be output are calculated every 100 ms. The pulses already output and the current wheel speed are included in the calculation. Including the wheel speed results in more constant output of the pulses when the vehicle is being driven at a constant speed. Via the backward counting implemented in the hardware of the output pulses it is ensured that no deviation of the output pulses from the specified value occurs. The deviation is limited to a maximum of one pulse per operating cycle.
The following formula applies for converting the current wheel speed into pulses:
- Pulses (1/s) = [wheel speed (rpm) X 48 (pulses/wheel revolution)] ÷ 60
The specified value calculated in this way is then compared with the actual number of pulses so far output and, if necessary, corrected slightly.
The following settings apply:
| Signal-ID 3000 |
|---|
| Value range 0 to 2117 rpm (wheel speed) |
| Value range 0 to 1694 pulses/s (PWM signal) |
| Pulse steps fixed at 50 % duty cycle |
Signal "PWM function test"
The PWM function test allows a PWM signal to be output at the PWM-capable output 09 or 10 for testing purposes. This enables the connected system to be tested.
The PWM function test can be selected in a menu item under the "Actuations" tab.
Freely parameterizable PWM signal for the discrete outputs 09 and 10
This function module is used to output a freely parameterizable PWM signal at the discrete output 09 or 10.
The internal inputs of the module can be configured via menu item "Assignment of PWM signals to outputs 09 and 10 - Signals". Outputs 09 and 10 each have an associated input to which any PWM signal can be assigned. Furthermore, outputs 09 and 10 each have an associated input with which the output can be activated or deactivated with a further signal.
The PWM signals can be adjusted via menu item "Properties → Freely parameterizable PWM signals". One frequency or one maximum value can be set per output.
The value range for the parameter "Frequency" is' 40.0 to 2000.0 Hz in 0.1 Hz steps.
Via the parameter "Maximum value", it is possible to set a limit value for the PWM signal at the input of the module as of which the PWM signal reaches 100 % at the output. If the limit value at the input is exceeded, the PWM signal at the output remains at 100 %.
For all values at the input which are below or equal to the parameterized maximum value, the duty cycle of the PWM output is calculated as per the following formula:
- Duty cycle (%) = [input value/maximum value] x 100 %
The output signal of the signal generator "Freely parameterizable PWM signal for output 09" (signal ID 3037) and "Freely parameterizable PWM signal for output 10" (signal ID 3038) must be parameterized for output at the PWM-capable discrete output 09 and 10.
The following settings apply:
| Signal ID | 3037 (Freely parameterizable PWM signal for output 09) |
|---|---|
| 3038 (Freely parameterizable PWM signal for output 10) | |
| Value range | 0 to 65 535 (PWM signal) |
| Value range | 0 to 100 % (PWM) |
| Output frequency | Freely selectable |
Example
A PWM output at a frequency of 550.0 Hz is required. The input signal has a value range of 0 to 2500. However, as of a value of 2400 a 100-% PWM should already be output.
The parameters of the signal generator are then as follows:
- Frequency_1 = (550.0 Hz) X 10 (due to 0.1 Hz resolution) = 5500
- Maximum value = 2400
A PWM output takes place with 2400 steps from 0 to 100 %.
| Parameterizable special module (PSM) control unit component description | GF54.21-D-5005P |