Stimmen - 5, Durchschnittliche Bewertung: 4.4
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Anleitung Zusammenfassung
The relationship between the output current and the resistor value is as follows: RMS OUTPUT CURRENT (Amps) = (.707)(0.002)(Resistor in Ohms) RMS Current Resistor Value RMS Current Resistor Value 1.0 698 2.5 1740 1.2 845 2.6 1820 1.4 988 2.7 1890 1.6 1110 2.9 2030 1.7 1180 3.0 2100 1.9 1330 3.2 2230 2.0 1400 3.3 2320 2.2 1540 3.4 2370 2.3 1600 3.8 2670 2.4 1670 4.0 2870 TABLE 3: RESISTOR VALUES WITH RESPECT TO OUTPUT CURRENT Closest 1% value selected WARNING! A current adjustment resistor is always necessary to keep the drive in a safe operating region. Do not operate the driver without a current adjustment resistor. When connecting the CURRENT ADJUSTMENT resistor between Pins 3 and 2 of Connector P2 the length of the leads should be as short as possible to help minimize the noise coupled into the driver . Refer to Figure 1 for TYPICAL HOOK-UP. 8 REDUCING OUTPUT CURRENT STEP MOTOR CONFIGURATIONS Step motors can be configured as 4, 6, or 8 leads. Each configuration requires different Reducing the output current in the MDM60001 can be accomplished by connecting an currents. Shown below are different lead configurations and the procedures to determine external resistor (1/8 watt or higher) between pins 1 and 2 of connector P2 and ocurrs their output current. automatically 1 second after the last positive going edge of the step clock input. See Figure 1 for TYPICAL HOOK-UP. 6 Lead Motors The amount of current per Phase in the reduction mode is related to the value of the current When configuring a 6 lead motor in a half-coil configuration (connected from one end of adjustment resistor and the current reduction resistor. When the current reduction circuit the coil to the center tap) use the specified per Phase (or unipolar) current rating to is activated, the current reduction resistor is paralleled with the current adjustment resistor. determine the current adjustment resistor value. This configuration will provide more This lowers the total resistance value, and thus lowers the per Phase output current. The torque at higher speeds. Use this to determine the current adjustment resistor value. relationship between the output current and the resistor's value is as follows: RMS Reduction Current (Amps)=(.707)(.002)xR(Adjust)xR(Reduction) R(Adjust)+R(Reduction) NOTE: When connecting the current reduction resistor between pins 1 and 2 of connector P2 , the length of the leads should be as short as possible to help minimize noise coupled into the driver. MOTOR SELECTION The MDM60001 is a Bipolar driver working equally well with both Bipolar and Unipolar Motor Configurations,( i.e. 8 and 4 lead motors and 6 lead center tapped motors). Motors with low current ratings and high inductance will perform better at low speeds, providing higher low-end torque. Motors with high current ratings and low inductance will perform better at higher speeds, providing higher high-end torque. Since the MDM60001 is a constant current source, it is not necessary to use a motor that is rated at the same voltage as the supply voltage. What is important is that the MDM60001 is set to the appropriate current level based on the motor being used. Higher voltages will cause the current to flow faster through the motor coils. This in turn means higher step rates can be achieved. Care should be taken not to exceed the maximum voltage of the driver. 9 When configuring the motor in a series configuration (connected from end to end with the center tap floating) multiply the per Phase (or unipolar) current rating by 0.7.Use this result to determine the current adjustment resistor value. WARNING! Step motors will run hot even when configured correctly, damage may occur to the motor if a higher than specified current is used. Most specified motor currents are maximum values. Care should be taken to not exceed these ratings. 10 4 Lead Motors Use the specified series motor current to determine the current adjustment resistor value. Four Lead Motors are usually rated with their appropriate series current, as opposed to the Phase Current which is the rating for 6 and 8 lead motors. 8 Lead Motors Series Connection: When configuring the motor windings in series, multiply the per Phase (or unipolar) current rating by 0.7. Use this result to determine the current adjustment resistor value. Parallel Connection: When configuring the motor windings in parallel, multiply the per Phase (or unipolar) current rating by 1.4. Use this result to determine the current adjustment resistor value. NOTE: After the current has been determined, according to the motor connections above, follow the procedure Determining Output Current above to find the current value. Then use Table 3 to choose the proper resistor value. 11 CONNECTING THE STEP MOTOR Phase 1&3 of the Step Motor is connected between pins 7 and 8 on connector P2. Phase 2&4 of the Step Motor is connected between pins 5 and 6 on connector P2. Refer to Figure 1 for TYPICAL APPLICATION HOOK-UP NOTE: The physical directio...