G340 INSTALLATION NOTES 
(March 31, 2002)

Thank you for purchasing the G340 drive. The G340 DC servodrive is warranted to be free of manufacturing defects for 1 
year from the date of purchase.  Also anyone who is dissatisfied with it or is unable to make it work will be cheerfully 
refunded the purchase price if the G340 is returned within 15 days of the purchase date. 

PLEASE READ FIRST BEFORE USING THE G340:

If you are not familiar with DC servodrives please do the following setup instructions with the motor on the bench before 
mounting it on the mechanism it will eventually run. This will allow you to get a baseline motor behavior of what to expect. 

Before you start, you must have a suitable encoder mounted and properly aligned on the motor. Follow the manufacturer’s 
instructions on mounting and aligning the encoder if the motor doesn’t already come with one. 

Next you must have a DC power supply suitable for the motor. Do not use a power supply voltage more than 5 volts in 
excess of the motors rated voltage. The power supply current rating must equal the maximum current you expect to run 
the motor at. 

Finally have a STEP and DIRECTION pulse source available. 

Before going on, turn the current LIMIT trimpot a quarter to half of full scale. Turn the GAIN trimpot fully off and turn the 
DAMPing trimpot to a quarter of full scale. The trimpots are single-turn, do not over-torque them with a screwdriver. 

REMOVING AND REPLACING THE COVER:

The STEP PULSE MULTIPLIER and the INPUT OPTION settings are jumpered internally. It is necessary to remove the 
cover of the drive to change these settings from their default values. Please follow the steps below on how to remove and 
replace the cover to avoid damaging the drive: 

REMOVING THE COVER: 

1) Remove the two 2-56 phillips-head screws on the bottom of the drive. 
2) Gently lift the back of the cover upward until the LED clears the rectangular hole 
3) Slide the cover backwards while still lifting until it clears the drive. 

REPLACING THE COVER: 

1) Make sure the LED is vertical relative to the drive printed circuit board. 
2) Slide the cover forward over the drive while lifting the back of the cover. 
3) When the cover is fully forward, look to see the LED is aligned with the hole. 
4) Gently press the cover down, making sure the LED moves into the hole. 
5) Replace the screws on the bottom of the drive. 

It is recommended to use small needle-nose pliers or tweezers to move the jumpers on the internal headers. 

G340 MULTIPLIER AND INPUT OPTION HEADERS:

MULTIPLIER OPTION HEADER 

The G340 has a built in STEP PULSE MULTIPLIER. This circuit puts out 1, 2, 5, or 10 pulses for every input STEP pulse. 
All motor moves will be in these increments. For example, if X10 is selected, then the motor will move 10 encoder counts 
for every STEP pulse sent to the G340. Move the jumper on the MULTIPLIER HEADER to select the desired multiplier. 
Do not operate the drive without a jumper. 

INPUT OPTION HEADER 

The INPUT OPTION HEADER allows the STEP and DIRECTION opto-isolators to be configured as either common 
ground or common +5VDC. 

If the G340 inputs are driven by a source that has only ground available, such as a PC parallel port, move the 4 jumpers 
on the header so that it looks like the COMMON GROUND setting. Connect the input driver ground to TERM 12 on the 
main connector. 

If the G340 inputs are driven by open collector transistors or standard TTL gates, move the 4 jumpers on the header so 
that it looks like the COMMON +5VDC setting.