User`s guide

8.3 CONNECTING & OPERATING STEPPER MOTOR

If the SSPCARD and associated cable are purchased with the PFE-1A, this section can be

disregarded.

A 9-pin AMP connector is supplied with the PFE-1A for those wishing to design and build

their own stepper controller or computer interface. Table 8-2 lists the pin numbers of the 9-

pin connector which are connected to the motor and the proper step sequence that these

lines must follow.

FUNCTION Q3 Q1 Q4 Q2 COMMON

MOTOR connect

WIRE COLOR black orange brown yellow red & red

PIN NO. FOR

PFE-1A CONN. 7 4 3 2 1

STEP 1 On On Off Off

SEQUENCE 2 Off On On Off

C.W. ROT. 3 Off Off On On

4 On Off Off On

1 On On Off Off

Table 8-2. Function and Color Code of Motor Wires Inside Unit.

Table 8-3 lists the pin numbers of the 9-pin AMP connector and their associated function.

Either a shielded or unshielded 9-wire cable can be used. Since the amount of current used

by the stepper motor is just a few hundred milliamps, small gauge wire can be used in the

cable. Cables of lengths up to 100 feet have worked successfully.

8.4 USING THE SAA1027 STEPPER DRIVER

The Signetics SAA1027 stepper motor drive IC is available from Optec for a small charge.

This 16-pin IC allows easy control of the stepper motor and requires only a few external

resistors, a 12 V DC power source and a two control lines from the computer or controller.

A typical circuit is shown in Figure 8-1.