Trim

Date 02-17-2002 01:20

The "trim" control on Miller (GMAW-P) series of wire feeders is basically the arc voltage control. When the Engineer/Marketing/Sales dude from Miller pops in here again, see if you can get him to expand on this. He'll want to sell you one.

By Tina Date 02-17-2002 01:40

Thanks.

By Mike Brace (**)

Date 02-18-2002 12:59

Tina: How "Trim" works on a Miller GMAW-P Pulse feeder set-up is this way. As you increase or decrease the Trim value you are changing the frequency of the arc. This means that the number of times the arc will go to Peak Current. Changing the frequency changes the burn off rate of the wire.

By DGXL

Date 02-18-2002 22:26

Mike,
Confused again about your response to the definition or function of the trim control on your feeders and controllers.

I thought the frequency was the pulse rate (PPS) value in the set up menu. Was also told by one of Miller's former employees this value was basically arc voltage. As this value is increased, the arc voltage increases (as noted on a calibrated test instrument). The "noise" (don't want to start more controversy with the terminology) increases in pitch, which is indicative of the frequency increase. But the display also shows a rise in voltage as well.

An increase in the trim also resulted in an increase in the arc length and vice versa, this time indicative of an increase in arc voltage.

By Mike Brace (**)

Date 02-19-2002 13:55

DGXL: Yes the frequency is the Pulses Per Second. As you increase or decrease the arc length by increasing or decreasing the PPS your arc length will increase or decrease because remember you have not changed wire feed speed. Thus the change in vlotage. When you pick a program on a 60M feeder the "Trim" defaults to 50. We have pre set an arc voltage that the control looks for to determine the frequency neede to have the proper arc length for a given wire feed speed. This is very important when you use the adaptive pulse mode. This is where the control tries to maintain a preset arc length no matter how wire stick out changes. Lets say the control is looking for 25 volts across the arc. as you increase wire stick out the voltage will increase and the control will reduce the PPS to bring the arc length back down to the 25 volts that it is looking for. The opposite happens when you reduce wire stick out. I hope this makes things clearer. If you have more questions call me at 920-735-4558 and I would be happy to talk to you

By DGXL

Date 02-20-2002 01:38

Thanks Mike,
Is your second response referencing when the controller or feeder is set in the adaptive mode?

By Mike Brace (**)

Date 02-20-2002 12:33

DGXL: On Miller pulse equipment adaptive or non-adaptive is selected on the control that is controling the pulse functions. Such as the Optima, 60M Feeder or in an Invision power source.

By DGXL

Date 02-21-2002 16:43

Just when I thought I had GMAW-P figured out.
Thanks Mike.