Lincoln Electric SP-255 manual OPERATIONB-3, Start Mode Selections, Process WIRE/GAS KEY

OPERATIONB-3

are held closed. The left pair will automatically contin- ue to increment or decrement the selection above it at a slow, steady rate as long as the key is pressed. The center and right pairs will continue to increment and decrement the selections above them at a slow rate, but then the rate will gradually increase until it becomes very rapid. This allows rapid setting from a small quantity to a large quantity or vice versa while maintaining an excellent resolution (i.e., 50 IPM to 600 IPM). However, when the trigger is closed, the changes will be at a steady, moderate rate to allow for proper “on the fly” control.

START MODE SELECTIONS

The SP-255 permits selection of Fast/Slow Run-In wire feed speed as well as adjustment of the start striking voltage, to optimize arc starting, using the starting screen display.

The starting screen (see Figures below) is displayed by pressing and holding both the PROCESS key and the TIMERS OFF key at the same time.

FIGURE 1

1.Run-In Speed

The SP-255 is factory set for FAST run-in (Figure 1) where the wire feed will accelerate directly to the preset speed. SLOW run-in will initially feed at 50 IPM until welding current is sensed, or for 2 seconds if feeding without welding (loading wire).

SLOW run-in may be selected using the left arrow keys which will toggle the starting screen display to SLOW (Figure 2) or back to FAST (Figure 1).

FIGURE 2

2.Start Voltage

The START voltage setting (Figure 1 or 2) may be offset from the factory programmed level (00%) by up to ±30% above or below pro- grammed level using the right arrow keys, or from the gun thumbswitch by positioning the screen cursor beneath the START display using the IPM-VOLTS key. (see “Gun Switch Keys” in this section).

3.Spool Gun Start Mode

If using optional spool gun mode (see “Making a Weld with the Spool Gun” in Accessories sec- tion), the RUN-IN portion of the starting screen is not functional and will not be displayed. The START voltage is adjusted as described above (Figure 3).

FIGURE 3

The starting screen is exited by pressing any key on the keypad except TIMERS OFF, IPM- VOLTS or any Arrow key. Closing Gun Trigger will also not clear the starting screen.

NOTE: It is not necessary to repeat the above procedure each time the unit is powered up. That is, the unit will remember the start mode settings from the previous power down and return you to that same state upon your next power up. thus, you need only perform the above procedure when you want to change the start mode settings.

When saving to Memory locations 1-5, the start mode at the time of saving will be saved into the memory location as well. Thus, the operator should be aware that when recalling a memo- rized procedure, he is also recalling particular start mode which will override any present start mode setting and remain in effect until either the mode is changed using the above proce- dure or until a memorized procedure containing another start mode is recalled.

PROCESS (WIRE/GAS) KEY

This key is used to display the Wire Type, Wire Diameter, and Welding Gas. Each combination of wire and gas dictates a unique relationship between the wire feed speed and the arc voltage. The SP-255 uses this unique relationship, along with the metal thickness, to set the proper values of wire feed speed and arc voltage. Therefore, it is very important that the wire type, wire diameter, and welding gas on the display match the actual wire type, wire diame- ter, and welding gas being used for the weld.

Left arrow keys—set Wire Type

JAN96 IDEALARC SP-255