Tweco FP-235DC - Manual (Page 14)

DIRECT CURRENT WELDING
Direct current DC welding is performed when the welding cables are connected to the DC+ (Positive) and DC-
(Negative) output receptacles. The FP 235 AC/DC offers you two DC welding options, straight or reverse
polarity.
To weld with straight polarity place the electrode cable plugged into the receptacle market DC negative and the
ground cable or work cable plugged into the receptacle marked DC positive.
STRAIGHT POLARITY DC welding is ideal for:
• Cutting steel;
• Hardfacing work;
• Build up work for heavy deposits.
Reverse current DC welding is performed with the electrode cable plugged into the receptacle marked DC pos-
itive and the ground cable or work cable plugged into the receptacle marked DC negative.
REVERSE POLARITY DC welding is ideal for:
• Overhead welding;
• Vertical welding;
• Cast Iron welding;
• Heavy Aluminum welding;
• Rivet welding;
• Sheet Metal welding;
• Low Hydrogen Electrode welding;
• Arc Bronze Electrode welding.
Most DC welding processes are performed in the reverse polarity position.
ADJUSTING AMPERAGE/INCREASING AMPERAGE
Simply crank the amperage adjustment handle on top of welder clockwise. As you crank the handle you will
see the amperage indicator located in the sight glass on the amperage setting scale move upward increasing the
amperage. Stop cranking when you have reached the desired amperage range.
LOWERING THE AMPERAGE
Simply crank the amperage adjustment handle on top of welder counter clockwise. As you crank the handle
you will see the amperage indicator located in the sight glass on the amperage setting scale move downward.
Stop cranking when you have reached the desired amperage range.
Be sure that the amperage adjustment handle is secured properly and that the
screw and nut are tight. Failure to do so will result in the inability to adjust amperage. Also be
careful not to over tighten the connections which could result in damage to the unit.
PREPARATIONS FOR WELDING
Your work should be performed in a safe, comfortable and organized area. The work area should be free of all
flammables with both a fire extinguisher and bucket of sand available for emergencies. To properly prepare
for welding follow these simple instructions:
1. Prepare an organized well lighted work area.
2. Follow the instructions for personal protection (page 1) for yourself as well as those around you.
3. Make sure you've studied all safety instructions found at the front of this manual.
4. Set up the workpiece and make the ground clamp connection.
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