Need Help!- boss servo geckodrive

[shawnc515]

hi all bought three gecko 320x servo drive a few months back and i am not having any luck trying to make these drives work with the servos, what happens is i wire it all up and turn it on and the drive will go to "in pos." then the motor will jump and and the drive faults, other times it will stay on "in pos." but if you try to move the motor shaft it stays locked untill you let go then it faults agen and goes back to reseting and jumping around until it locks agen (i have the jumper going from enc. 5v to err/res), here is what i have tryed so far, another encoder (no change), a servo from an old printer that had its own encoder (this worked perfect). the power supply im using is the original from the machine i just ran it from 110v insted of 220v to get the voltage down to the gecko's specs (now at 68v dc), two more things is i do have the encoder running of a lab grade power supply and i got the one motor to work properly once with a lab grade power supply at 30v but only 1 amp.

motor specs dc brushed 30 in/lb
stall current 14.6 amps
max voltage 146
max rpm 6000
kt .233

encoder specs BEI model #e25g-4sr-250-abzc-8830-led-sm18-s
vdc in 5v
cpr 250 quad
o and the date of mfr. 3/02/89 lol

edit: hooked one of the drives back up to my lab power supply and that motor works perfect i then swithed only the main power wires back over to the larger power supply (the one i intend to use all the time) and the problems came back so is it posible the large power supply needs a bigger filter cap even though its only running half the voltage it normally runs (65-68v dc insted of 130v dc).

thanks

[jalessi]

Shawnc515,

See the attached file for power supply capacitor requirement.

Jeff...

[shawnc515]

i come up with 11765 uf at 68 volts my curent caps are 2 5000 uf 200vdc (these things are huge).

thanks
shawn

[shawnc515]

anyone please im at a loss here, is the motor to big for the drives?

[H.O]

Hi,
You mentioned you are powering the encoder from a bench power supply...
If so you must connect the ground of the bench supply to ground of the main power supply. In other words ENC GND must be connected to POWER GND.

/Henrik.