Specifications

SECTION 3 STEP MOTOR DRIVER

SECTION 3 - STEP MOTOR DRIVER

MODEL – DPD72401, DPK72402, & DPK72403 (BLD72 Driver)

BILEVEL DRIVE

The basic function of a step motor driver is to provide the rated motor phase current to the motor windings in the

shortest possible time. The bilevel driver uses a high voltage to get a rapid rate of current rise in the motor

windings in the least amount of time. When reaching the preset trip current, the driver turns off the high voltage

and sustains the current from the low voltage supply.

HALF-STEP/FULL-STEP

Users have a choice of full-step operation or half-step operation. Full-step operation occurs by energizing two

phases at a time, rotating a typical motor 1.8 degrees per step. Half-step operation occurs by alternately

energizing one, and then two, phases at a time, rotating the motor 0.9 degrees per step. Full-step operation is

suggested for applications that specifically require that mode, such as when retrofitting existing full-step systems.

MOTOR ON/OFF INPUT

The motor on/off input allows de-energizing a motor without disturbing the positioning logic. After re-energizing

the motor, a routine can continue. This reduces motor heating and conserves power, especially in applications

where motors are stopped for long periods and no holding torque is required. If holding torque is required (such as

when lifting a load vertically), then this function should not be used. This output is internally connected to the

Indexer. See Section 8 Command Descriptions for further information on Current Hold Command.

FAULT PROTECTION

There are 3 types of fault detection. When a fault is detected, the driver turns off the motor current and the red

Fault LED indicates which type of fault occurred. (Located on the top of the driver pack.)

1 LED - Slow Blink shorted wire in the motor or cable

2 LED - Fast Blink open wire in the motor or cable

3 LED - ON Steady ground fault (voltage shorted to 0V)

TABLE 3: FAULT LED

If the driver goes into a fault condition, the fault may be reset by turning the power OFF for at least 15 seconds or

by pulling the RESET FAULT input (terminal 4) to a logic “0" for at least 100ms.

SETTING THE KICK CURRENT

The Kick Current should be set to the Motor’s Rated Unipolar Current. For example, a 34D309 is rated for

4.5A, so the Kick Current Potentiometer would be set somewhere between the 4A and 5A indication.

GROUNDING

The unit should be properly grounded. Shielded cable should be used to preserve signal integrity.

Contact factory for grounding recommendations.