6
Maintenance and care
6/2
6.3.1
Test intervals and scope
A quarterly partial test and an annual extensive test are to be carried out. The extensive test must
also be carried out each time that repairs are made; in the case of heavy use, the period can be
reduced (e.g. to 6 months when used at construction sites). In the extensive test, the machine must
be opened and cleaned according to the section entitled “Cleaning”. Only exterior cleaning is
required for the partial test.
Partial test
Full test
a) Visual
check
a) Visual
check
b)
Electrical test: measurement of Protective
conductor resistance
b)
Electrical test: measurement of
• Protective conductor resistance
• Insulation resistance
• Leakage currents
• Open circuit voltage
c) Functional
test
c) Functional
test
6.3.2
Documentation of the test
The result of the test must be documented to show the following clearly:
•
Identify the tested machines,
•
The date of the test
•
The time of the next test and
• The
results
for later reference. The machine must be marked if the test is successful (e.g. with a test plate).
This plate must include the date of the next repetition test.
6.3.3
Visual inspection
Given below are the main points in the full test. The points to be tested with the machine open are
not required for the partial test.
1.
Torch/stick electrode holder, welding current return lead clamp
2.
Leads including plugs and couplings
3.
Open plugs and couplings
4. Casing
5. Open
casing
6.
Special features of the welding power sources for plasma cutting
7.
Operating, message, safety and adjustment devices
8. Other,
general
condition
6.3.4
Measurement of protective conductor resistance
Measure between the plug earthed contact and accessible metal parts, e.g. casing screws. During
the measurement, the connection lead must be moved across the entire length, but especially
close to the casing and plug inputs. This should uncover any interruptions in the protective
conductor. All conductive parts of the casing accessible from outside should also be tested to
ensure a correct PE connection for safety class I.
The resistance must not exceed a mains connection lead 0.3
Ω
up to 5m in length. For longer
leads, the permissible value increases by 0.1
Ω
per 7.5m of lead.
