TEKHMANN TWI-200 B, Instruction Manual

Page: 21 / 40

21
Connecting welding cables
Any connection to the welding circuit must be performed when the machine is disconnected from the
supply line.
Welding cable with electrode holder
is connected to the positive pole (+) (see «Welding»).
Cable with functional terminal is connected to the negative pole (-), its other end is connected to the
piece to be welded or operating area as close to the welding seam as possible.
WARNING! Connected cables must be inserted securely in the terminals, which will
ensure good contact. Loose connections will lead to overheating, timely wear, loss of
efficiency and damage to the terminals.
Do not use welding cables of more than 5 m in length.
Never use metallic constructions which are not the part of the piece to be welded instead of cable with
functional terminal, as this will violate safety and lead to poor welding.
Welding
WARNING! Most welding electrodes are connected to the positive pole, although some types
have to be connected to the negative pole. It is important to follow manufacturer’s instructions on the
package of the electrodes, as they indicate right polarity of the welding electrode as well as the most
suitable current for welding operations.
Adjust welding current according to diameter of used electrode and according to type of welding seam.
Below is the table of admissible current according to diameter of the electrode:
Electrode diameter, mm
Welding current
, А
Min Max
1,6 25 50
2 40 80
2,5 60 110
3,2 80 160
4 120 200
Pay attention, that depending on the diameter of the electrode, higher values of welding current are
used for welding in lower position, whereas vertical welding (or welding in vertical position, so called
«overhead welding») requires lower values of welding current.
Except for welding current power mechanical characteristics of the welding seam are determined by
other parameters:
- diameter and quality of the electrode;
- arc length;
- speed and position of welding;
- proper storage of electrodes (they must be protected from environmental exposure and kept in a
special package).
Welding
When welding ALWAYS wear protecting mask with special goggles for eye protection from strong
light emission, generated by electric arc. Mask allows watching the process of welding and protects
the user.
Keeping mask
IN FRONT OF YOUR FACE, lead the electrode on welding area. Hand movement must
resemble lighting a match. This is the right way to strike the arc.
WARNING! Never knock with electrode trying to strike the arc, as this may lead to its damage
and will hamper arc striking.