Thank you for purchasing the G251 drive. The G251 microstep drive is warranted to be free of manufacturing defects for 3 years
from the date of purchase. Anyone who is dissatisfied with it or is unable to make it work will be refunded the purchase price if
the G251 is returned within 90 days of the purchase date and is in like-new condition.
PLEASE READ FIRST BEFORE USING THE G251
Before beginning, be sure to have a suitable step motor, a DC power supply suitable for the motor and a current set resistor. The
motor’s rated phase current must be between 0 amps and 3.5 amps and the current set resistor may be a 1/4 watt, 5% part. Finally
have a STEP and DIRECTION pulse source available.
G251 TERMINAL WIRING
The G251 uses a 12 position 3.5mm terminal block. The wire gauge must be between 16 and 26 (AWG) and the wire must be
stranded. Do not solder tin the wire strands as this will cause it to fatigue over time and it will eventually break. Do not exceed 30
in-oz (0.2 Nm) torque on the terminal screws.
TERMINAL 1
Power Ground
Connect the negative (black) lead of your power supply to this terminal.
TERMINAL 2
Power (+)
Connect the positive (red) lead of your power supply to this terminal. It must be b15VDC to
+50VDC.
TERMINAL 3
Current Set
Connect one end of your current set resistor to this terminal.
TERMINAL 4
Current Set
Connect the other end of your current set resistor to this terminal.
TERMINAL 5
Motor Phase A
Connect one end of your “Phase A” motor winding here.
TERMINAL 6
Motor Phase /A
Connect the other end of your “Phase A” motor winding here.
TERMINAL 7
Motor Phase B
Connect one end of your “Phase B” motor winding here.
TERMINAL 8
Motor Phase /B
Connect the other end of your “Phase B” motor winding here.
TERMINAL 9
Direction
Connect the DIRECTION signal to this terminal.
TERMINAL 10
Step
Connect the STEP signal to this terminal.
TERMINAL 11
Disable
This terminal will force the winding currents to zero when shorted to ground (TERMINAL 12).
TERMINAL 12
Common
Connect this to your logic (controller) ground.
