Pacific Scientific 6410 Stepper Driver

2.6 Enable polarity selection

The polarity of the enable input (ENABLE+/ENABLE -) can be reversed through J6 jumper 5-6. In the default (jumper removed) state, the driver power level is enabled when the optocoupler has no current (i.e. suspended in the enabled state), and disabled when the optocoupler is driven. This allows 6410 to function normally even without connecting the enable signal. After the jumper is installed, the enabling optocoupler must be driven to enable the power stage. Regardless of the polarity, there is a delay of approximately 500ms between the activation of the enable signal and the actual activation of the power level to avoid transient shocks.

Protection circuit and reliability

6410 is equipped with comprehensive fault protection mechanism. The short-circuit protection circuit monitors in real-time whether there is a phase to phase or ground short circuit at the motor output terminal. Once a short circuit is detected, the driver immediately disables the output and maintains the fault state until it is powered on again. Overvoltage protection is limited for situations where the bus voltage exceeds 75V (in conjunction with an external clamp circuit). In addition, the driver also monitors whether the internal low-voltage power supply exceeds the tolerance range. All of these faults will cause the 'Enabled' output signal to become invalid, and users can diagnose it through an external indicator light or PLC input. The driver has passed UL 508C (Class R) certification, document number E-137798, and complies with CSA C22.2 No.142-M1987 process control equipment standard.

Installation and Wiring Guide

4.1 Mechanical Installation

The 6410 drive is designed for book case installation, and it is recommended to fix its back or side panel to a heat sink (aluminum plate or heat sink) to ensure that the chassis temperature does not exceed 60 ° C. The heat sink needs sufficient thickness and surface area for passive heat dissipation. If no heat dissipation plate is added and no fan is used, the maximum allowable output current is 2.5A RMS at an ambient temperature of 25 ° C (up to 5A with optional heat sink); At an ambient temperature of 45 ° C, the temperature drops to 1.25A and 2.5A respectively. It is strongly recommended to use a temperature probe to directly measure the chassis temperature during actual operation, taking into account the worst-case ambient temperature margin. The installation direction must be vertical, with at least 4 inches (10cm) of unobstructed space reserved around to ensure air convection. The weight of the drive is approximately 1.0 pound (0.45kg), with dimensions of 4.30 inches high x 4.75 inches wide x 1.10 inches deep (approximately 109 x 121 x 28mm), and two mounting holes are provided on the back and side.

4.2 Electrical Connections

6410 has three connectors in total:

J1 (9-pin D-sub female socket): Signal interface, including STEP+/-, DIR+/-, ENABLE+/-, and ENABLED output (collector and emitter). All inputs and outputs are isolated by optocouplers. The minimum conduction currents for STEP and DIR inputs are 5.5mA and 3.0mA, respectively, with a maximum reverse voltage of 5V. Users can use TTL totem pole output or higher voltage (up to 30V) interface circuits, which require appropriate resistors in series. The ENABLED output is an NPN transistor with an open collector and emitter lead, which conducts when the driver is enabled and fault free, with a saturation voltage drop of less than 0.5V (when filled with 2mA).

J2 (3-pin PCD terminal): Power input, pin 1 is DC -, pin 2 is DC+(24-75Vdc, maximum 5A), and pin 3 is ground. It is necessary to ensure that the voltage does not exceed 75V under any transient conditions, which is the most common cause of driver damage. The positive and negative DC wires should be twisted pair, with a length not exceeding 3 feet (approximately 0.9m), and a bus capacitor should be placed near the driver end.

J3 (5-pin PCD terminal): Motor connection, pins 1 and 2 are A-phase (A and A ̅), pins 3 and 4 are B-phase (B and B ̅), and pin 5 is the motor housing ground. Pacific Science provides prefabricated SPC-xxx-6410 series motor cables (xxx is the length in feet, up to 50 feet), which users can also make themselves. For four wire motors, directly connect A, A ̅, B, B ̅; For eight wire motors, parallel or series connection methods can be selected to adapt to high-speed high torque or low-speed high torque requirements, respectively. It is recommended to use # 16 AWG wire gauge for all motor phase wires, with 3-4 twisted pairs per inch and optional shielding layer.

4.3 Power Supply and Bus Capacitor Design

6410 is powered by an external DC power source. The most economical solution is to use a non regulated power supply composed of transformers, rectifier bridges, and capacitors. When selecting a transformer, it is necessary to consider the maximum input voltage, load regulation rate, and line fluctuations to ensure that the peak voltage after rectification does not exceed 75V. For example, a transformer with a nominal 115VAC input and 40VAC secondary can achieve a peak voltage of 60.7V under+10% line fluctuations and light load conditions, which is still within the safe range. Recommend using Bus MDA 10A slow melting fuse in series between rectifier bridge and capacitor. The minimum capacity of the bus capacitor depends on the current setting and bus voltage. For example, under a 70V bus and 5A setting, it is recommended to use a 6000 μ F capacitor with a 120Hz ripple current rating of not less than 5A and a working voltage of not less than 91V. For multi axis systems, each 6410 should be independently connected to a capacitor to avoid daisy chain power lines. Regenerated energy may cause the bus voltage to pump up. If the voltage exceeds 75V during deceleration, a clamp circuit (such as a power Zener diode or active discharge circuit) needs to be added.