Miller Electric OM-842 manual Manual Gtaw Mode, Procedure Up To Pulse Mode Selection

8.Press Right/Increase. The microprocessor control will enter the Ready condition.

9.In the Ready condition the microprocessor control is ready to have another program entered or to execute a program. For information on executing a program, see Section 6.

If the Process Selector switch is in a dc output position, the choices are Start Only high frequency or Disabled high frequency.

10.When the desired choice is shown, press Right/In- crease to advance to the next display. The display shows:

5-4. Manual GTAW Mode

NOTE	If needed, see Section 5-1B for
	information on selecting and defining
	a parameter.
NOTE	Weld output options, such as the use
	of pulsing, high frequency, and ac or
	dc output, affect how a program is
	entered in the Manual GTAW mode.
	Be sure to follow all applicable steps,
	and only the applicable steps, as
	determined by the selected options.

A.Procedure Up To Pulse Mode Selection

1.Turn on welding power source, if applicable.

2.Place the Mode Selector switch in the Manual GTAW position.

3.Place the Program/Run/Reset keyed switch in the Re- set position, and then in the Program position. The initial displays will be shown.

4.When the repeating displays (explained in Section 5-1F) are shown, press Right/Increase.

If the Process Selector switch is in the ac output posi- tion, go to Step 5. If the Process Selector switch is in a dc output position, go to Step 8.

5.The display shows:

# 0 X B A L A N C E C O N T R O L

E N = X X % E P = X X %

6.If applicable, define the program number (see Section 5-1C). Define the electrode negative value for the ac output square wave (see Section 4-3) as desired.

The range for percentage of waveform in electrode negative is 46% to 68%, in increments of 2%.

7.Press Right/Increase, and go to Step 8.

8.The display shows:

H I G H F R E Q U E N C Y

>X X X X X X X X X <

9.Press Parameter Select to display the desired choice.

If the Process Selector switch is in the ac output posi- tion, the choices are Start Only high frequency or Continuous high frequency.

# 0 X P R E F L O W

TI M E = X X .X

11.If applicable, define the program number (see Section 5-1C). Define the shielding gas preflow time as desired.

The range for preflow is 0.0 to 25.0 seconds, in incre- ments of 0.1 seconds.

12.Press Right/Increase, and the display shows:

# 0 X S T A R T L E V E L

TI M E = .X X X A M P S = X X X .X

13.Define the start level time and amperage as desired.

When properly used, start level eases arc starting by allowing the use of an amperage value that is higher than initial amperage for a short length of time.

The range for start level time is 0.0 to 15.0 seconds, in increments of 0.1 seconds. The range for start level amperage varies from 2.0 to 400 amperes, in incre- ments of 1.0 amperes.

14.Press Right/Increase, and the display shows:

* * P U L S E M O D E I S * *

>X X <

15.Pressing Parameter Select toggles the display be- tween pulse mode On and pulse mode Off. Three possibilities exist at this point, as follows:

Pulse mode On is desired and pulses are to be defined as time spent in peak current and background current (see Step 16).

Pulse mode On is desired and pulses are to be defined as a frequency, with peak current defined as a percent- age of the total period (see Step 16).

Pulse mode Off is desired (see Step 17).

16.To define pulse mode On, proceed as follows:

a.Be sure the desired means of defining pulse mode has been selected according to Section 2-4.

b.Use the Parameter Select push button to select pulse mode On, and press Right/Increase to ad- vance to the next display while ”On” is displayed.

c.If pulses are being defined as time values, go to Section 5-4B.

If pulses are being defined as a frequency, go to Section 5-4C.

17.To define pulse mode Off, proceed as follows:

a.Use the Parameter Select push button to select pulse mode Off, and press Right/Increase while ”Off” is displayed. The display shows:

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