FAST COUNT (MOTOMAT)
Symbol for the function in the Edit / Simulation / Monitoring page.
This function counts the pulses input to the I1 input at rates above 100 Hz. The value of the I2 input determines the counting direction. If I2 is set to 1 when a rising edge occurs on I1, the counter is incremented. Conversely, the counter is decremented if I2 is set to 0. It is not necessary to make any connections between pins I1 & I2 and the FAST COUNT trade function since the links are implicit.
Inputs :
- INHIBITION : Any pulse input to fast input I1 is not taken account of when the inhibition input is set to 1.
- RESET : The POSITION counter is reset to zero when the RESET input is at 1.
Any inputs not connected have a neutral value for this function : 0.
Outputs :
- POSITION : Current value of the counter.
- SPEED : Number of pulses over N times 100 ms, where N is the PERIOD parameter.
Configuration Window
- PERIOD : Pulse count time period used to determine the SPEED.
- MEMORY FUNCTION : Provides for setting the reaction on return of mains power after a power loss.
Performance Characteristics :
Communications between the PC and the logic controller, the settings, the DISPLAY functions, etc… may distort the measurement This trade function can only be used with controllers running on 12VDC or 24 VDC power supplies. This trade function cannot be simulated. Limitations Related to the Duration of the Cycle Time The internal characteristics of the M2 impose limits on the number of events captured per cycle time. The limit is 72 events, and cannot be changed.
The frequencies shown in the tables below correspond to the average frequency of the signal which the unit can store and process over the cycle timeframe. For lower values and/or long cycle times, this does not prohibit higher instantaneous values, on condition that the average frequency within one cycle remains systematically below the figure in the table and that the limitations stated above are complied with.
Cycle Time Duration
10ms
20ms
30ms
40ms
50ms
Max Input Frequency
4.0KHz
3.6KHz
2.4KHz
1.8KHz
1.44KHz
- Since the speed output is a 16-bit byte with a sign, the table below shows the maximum period values that may be used without incurring overshoots.
Fréquence entrée moyenne |
4.0KHz |
3.6KHz |
2.4KHz |
1.8KHz |
1.44KHz |
Période maximale pour calcul de vitesse (x 100 ms) |
81 |
91 |
136 |
182 |
227 |
Characteristics of the Input Signal on I1
- The characteristics shown below are - except where otherwise specified - for the standard characteristics of the controller.
- The rise time tr and fall time tf are both 1µs.
- For signals above 625 Hz, tu must be equal to td . Below 625 Hz, tu and td must be greater than 800µs.
- The signal on the I2 input used to take account of the counting direction must be present at least 400µs before and after the counting edge on the I1 input.
The table below shows the frequencies capable of being measured on the I1 inputs for two voltage ranges. These values are only representative of the limitation imposed by the measurement electronics for a Millénium powered at 24VDC.
VL min (Volts) |
VLmax (Volts) |
VHmin (Volts) |
VHmax (Volts) |
Fmin (Hz) |
Fmax (Hz) |
0 |
5 |
15 |
28.8 |
625 |
2200 |
0 |
1 |
17.5 |
24 |
2300 |
4000 |
Fmin represents the minimum frequency of the input signal for which operation is guaranteed. Fmax represents the typical maximum frequency at ambient temperature but with a slight loss in accuracy. (error < 1% for this frequency). The typical values shown above are indications. Statistically, most controllers will be within these values, but it is possible that some items differ to a greater or lesser extent. The maximum frequency of 4000 Hz must not be exceeded.