User`s manual

123

FAULT

POWER

7 8

against shorted and open motor wires. If any type of fault is detected, the driver FAULT PROTECTION

will turn off current to the motor, and the Fault LED will indicate which type of

fault occurred. There are three types of fault detection. When a fault is detected, the driver

BILEVEL DRIVE occurred. See the Troubleshooting section for more information.

The basic function of a step motor driver is to control the motor winding

currents. Motor performance is determined by how fast the driver can increase

and decrease the winding currents. A rapid rise in winding current is achieved

by applying a high voltage directly to a motor winding until a desired current

level is reached. Then a low voltage is applied to maintain a suitable holding

current level. When a motor winding is de-energized (turned off), a rapid

decrease in winding current is achieved by routing the energy in the collapsing

field back to the power supply through a high voltage path. The high voltage

supply furnishes the energy necessary to maintain motor output torque at high

step rates thus providing high mechanical power output. The low voltage supply

provides much of the current needed at low step rates and all of the holding

current.

Bilevel drivers do not use high frequency switching techniques as chopper

drivers do. Consequently, they do not create the EMI, RFI, and motor heating

problems that are associated with chopper drivers.

ADJUSTING THE KICK CURRENT

The kick current level is the desired phase current level that the high voltage

provides each time a step is taken. The high voltage is turned off when this

level is reached. To obtain a proper setting, refer to the silkscreen on the side

of the unit and adjust the potentiometer to the rated phase current of the motor.

This internally sets the kick current 40% over the rated phase current.

WARNING: The kick current level must be set before operating a motor.

FUNCTION JP1 JP2 JP3

NEGATIVE GOING CLOCKS 1-2 X X

POSITIVE GOING CLOCKS 2-3 X X

TERMINAL 5 = CCW X 1-2 X

TERMINAL 5 = DIRECTION X 2-3 X

GROUND FAULT DETECTION ENABLED X X 2-3

GROUND FAULT DETECTION DISABLED X X 1-2

TABLE1: JUMPERS SETTINGS

turns off the motor current and the red Fault LED indicates which type of fault

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)

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.

JUMPER FUNCTIONS/LOCATIONS