8760 Driver Box

Description

For those who wish to run stepper motors on their Sherline CNC-ready machines, we now offer the driver box and power supply as a separate item.

The anodized aluminium box contains four drivers.  Each outputs to its own cable, labelled X, Y, Z, and A, that plugs directly into Sherline's P/N 67127 stepper motors.  These stepper motors are pre-wired with a plug to match that on the end of the driver box cables, making hook-up easy and fast.  A 25-pin parallel cable (included) runs from the driver box to the parallel port on a computer. Power comes from an external power supply (included) that plugs into the box.  Also included is a CD that contains the correct version of the Linux operating system and EMC control program that Sherline uses in its CNC system, should you wish to install them on your own computer. The operating instructions for CNC and a short course in writing G-code by Joe Martin are also included.  The driver box has its own power on/off switch and a bright red LED that indicates when power is on. It operates on either 110 or 220 VAC power (switchable).

As an alternative to Linux operating system and EMC control program, Mach3 software for Windows® operating system is available

Technical Specifications, P/N 8760 Stepper Motor Driver

Power Supply:

Input: 100-240 VAC, 47-63 Hz, 3A (automatically adapts to incoming voltage)
Output: 24 VDC, 4A

Parameters:

∙ Logic high levels should be greater than 2 volts.
∙ Logic low should be less than 1/2 volt.
∙ Step pulses are active low.
∙ Step pulses should be at least 22 microseconds long.
∙ The lines labelled as EMC inputs or outputs can be disregarded in other systems.
∙ For use with software other than EMC, make sure your software addresses the correct I/O lines for step and direction as shown below.   Sherline is not able to provide assistance for other programs. For help with the EMC software, see http://www.linuxcnc.org/
∙ We recommend at least an 800 MHz Pentium class computer or faster for use with the frequency mode.

 

In operation, the power to the motors will be reduced to half current after 3 seconds of inactivity. This can be changed to 1/4 power with a jumper on H1.

DB25 pin out:

1 - Input from EMC (may be ignored in other systems)
2 - X Direction
3 - X Step
4 - Y Direction
5 - Y Step
6 - Z Direction
7 - Z Step
8 - A Direction
9 - A Step
10 - NC
11 - Output to EMC (may be ignored in other systems)
12 - Output to EMC, XYZ home (may be ignored in other systems)
13 - NC
14 - Input from EMC, C1 (may be ignored in other systems)
15 - NC
16 - Input from EMC, C2 (may be ignored in other systems)
17 - NC
18-25 - Ground

Headers on PC board:

H1 - Will reduce current to 1/4 after 3 seconds
H2 - Unimplemented H3 - Will remove power from drivers immediately (panic stop)
RESET - Will hold the drivers in reset condition

Motor Connectors:

∙ 5-pin DIN male
∙ Five to 30 volts (better performance at higher voltage)
∙ 2 amp unipolar configuration
∙ 800 steps per revolution (micro stepping), equates to 16,000 steps/inch with .050" pitch lead screw

 

In Figure 1 below, wire colours of the 8-wire SKC brand stepping motors are shown. Figure 2 shows pin layout and wire colours for the 6-wire NMB brand motors now used by Sherline. Other brands of motors may use other colours.

(A)  - Coil A uses the black and green wires with black/white and green/white as the centre tap.

(B)   - Coil B uses blue and red wires, with blue/white and red/white as the centre tap.

Figure 1—(Above) Shinano Kinshi Motor and plug colour codes for 8-wire motors.

 

 

Figure 2—Sherline NMB six-wire motors have only two wires from the centre taps, and the colours are different. For 6-wire motors, the order would be (counter clockwise starting at upper left): Yellow, red, black + white, orange, brown. Again, this view shows the connector from the back side where the wires would be soldered on.

 

8765 Driver Box and two 67127 stepper motors (lathe)

8770 Driver box and three 67127 stepper motors (mill)

                               

8765: Driver Box and two 67127 stepper motors (lathe)                             8770: Driver box and three 67127 stepper motors (mill)

The 8765 and 8770 kits are designed for those who wish to purchase a CNC ready lathe or mill and use their own computer.

The 8760 is for applications where stepper motors are already in place.

Sherline Stepper Motors

Sherline offers stepper motors with your choice of a pre-wired connector plug (P/N 67127) for use with our individual axis or CNC system drivers, or with six raw wire leads (P/N 67130 for general use.  Flats are ground onto the shafts to accommodate the coupler and hand wheel setscrews.