Linz electric E2W10 DC Mode D'emploi Et D'entretien page 11

the rated one. Consider that the outlet voltage can vary almost proportionally to the speed variation.
Operation in particular settings
If the alternator/welder is going to be used within a soundproof generating set, make sure that only fresh air enters in it. This
can be ensured by placing the alternator's air inlet near the external air intake. Moreover, consider that the quantity of air
required is: 4 m3/min.
Bearings
The bearings of the alternators/welders E2W10 DC are self lubricated and therefore they do not require maintenances for a
period over 30000 hours. When it is necessary to proceed to the general overhaul of the generating set it is advisable to wash
the bearings with a proper solvent.
Slip-rings, brush holder and brushes
The set composed by slip-ring, brush holder and brushes is designed to guarantee a long and safe service. Therefore no
maintenance is required for at least 2000 hours of operation.
In case of bad working of the machine with accidental de-energising or irregular current supply, it is necessary to carry out the
following simple operations:
1) Clean slip-ring and brushes and check if their mechanical position is correct.
2) Check the position of the brushes; they must be lean for all their width within the surface of the rings.
3) Check the brushes and eventually replace them if worn.
Diode bridge
A 25A-800V diode bridge is used as standard.
Checkout of three-phase diode bridge
Check out of single diode valves of the rectifier bridge can be executed either with an ohmmeter or with a battery and relative
lamp as described her below. A diode valve works regularly when:
- the resistance, calculate with an ohmmeter, is very low in one sense and very high in the other.
Three phase fixed diode bridge (figure 3)
- with battery and lamp, it is verified that the ignition of the lamp is possible only with one of the two possible connections,
as shown in figure 4: A) Lamp Off; B) Lamp On.
Note for disassembly
Before extracting the rotor from the case it is necessary to remove the brush-holder.
7. DESCRIPTION OF ALTERNATOR/WELDER WORKING PRINCIPLES
On the front panel you can find the following components (figure 7):
1 - Function & Range of current selector (3 - positions)
2 - Welding current selector (6 - positions)
3 - Quick plug of (+) welding
4 - Quick plug of (-) welding
Starting of the set (drive motor and alternator/welder)
During every start, selector (1) must be on position "GENERATOR " to guarantee the alternator self-energising .
Working as alternator
In this function selector (1) must be on position "GENERATOR" to allow to use of the sockets mounted on the rear panel.
Working as direct current welder
In this function the selector (1) must indicate the current range indicated on the packing of electrodes that will be welded.
Welding cables (3) and (4) must be connected to the correct polarity also depending from the instructions on the electrode
packing. At last, using main welding current selector (2) it is possible to set the most suitable current to weld the used electrode.
Important: every time the machine is used as welder it is necessary to disconnect the load from the sockets of the alternator to
avoid any damage that can be caused by voltage fluctuations while the machine is welding.
8. SAFETY INSTRUCTIONS FOR WELDING
- Avoid any direct contact with the welding circuit, the arc striking tension of the welding outlet can be dangerous in some
circumstances.
- Effect checkout and repairing operations of the system only when the generator is completely stopped.
- Accomplish equipotential connection of all metallic parts according to national safety rules, as well as for any eventual
connection to earth
- Do not use the machine in damp or wet places or in the rain.
- Do not use cables with worn insulation or loose connections.
- Do not weld on containers or pipes which have held flammable materials or gaseous or liquid combustibles.
- Remove from working area all flammable materials like wood, paper, rags, etc.
- Provide an adequate ventilation or facilities for removal of welding fumes near the arc.
- Always protect your eyes with fitting adiactinic glasses mounted on welding masks or helmets. Use proper gloves or
protecting clothes avoiding the exposure of your skin to the welding arc.
9. INSTALLATION
Site
The machine must be located in a place where openings for inlet and outlet of cooling air are not obstructed. Furthermore check
that conductive dusts, corrosive vapours, humidity, etc. will not enter into the machine.
Connection of the welding cables
Cable with "electrode holder" gun is normally connected to positive (+) terminal (3). The earth return cable is normally connected
to negative (-) terminal (4) of the welder; earth terminal, in the opposite side of the cable, must be connected to the work piece or a
metallic work bench as near as possible to the joint to be made. Connected cables must be turned fully into the quick plugs (3) and
(4) to ensure a good electrical contact (loose connections will cause overheating with consequent rapid deteriorations of the same).
Avoid using welding cables having length over 10 m.
10. WELDING
This welder is designed to weld all kind of electrodes: rutile, basic, inox and cellulosic.
The majority of the covered electrodes has to be connected to pole (+) but some electrodes has to be connected to the negative
pole (-). Always verify the instructions about polarity and most suitable current values on electrodes packing.
Welding current must be regulated according to electrode diameter and the type of joint to be effected.
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