8
STATIC CHARGE
EN
VALIDATION CLASS, VALIDATION TYPE AND MEASURING TOOLS
Validation class :
The validation class may be «Standard» or «»of precision».
Standard class :
± 10% of the real value between 25 and 100% of the maximum setting.
± 2,5% of the maximum setting between 0 and 25% of the maximum setting.
Class of precision :
± 2.5% of the real value between 40 and 100% of the maximum setting.
± 1% of the maximal setting between between 0 and 40% of the maximum setting.
Validation type :
The type of validation may be «consistence» type or «precision» type.
Consistence type :
Validation on a device with potentiometer adjustment.
Precision type :
Validation on a device with adjustment by digital display.
Voltmeter :
Device used to measure the output voltage.
Clampmeter :
Device used to measure the output current (AC position for TIG AC).
Measuring tools:
Measuring tools must be at least twice and preferably 5 times more accurate than the required
accuracy for the validation class.
CONVENTIONAL LOAD
Standard asks that the current sources (MMA and TIG) and the voltage sources (MIG) must be checked under conven-
tional voltage and current. Formulas given by the standard are:
MMA & SUB ARC :
U(V) = 20V + 0.04 x I(A) below 600A
TIG :
U(V) = 10V + 0.04 x I(A) below 600A
MIG :
U(V) = 14V + 0.05 x I(A) below 600A
For MMA and TIG products, behaving as a current power supply, the voltage is adjusted due to the
resistive load to match the conventional voltage.
For MIG products, behaving as a voltage power supply, the current is adjusted due to the resisitive load
to match the conventional current.
Current (A)
MMA & SUB ARC (V)
TIG (V)
MIG (V)
40
21.6
11.6
16.0
60
22.4
12.4
17.0
80
23.2
13.2
18.0
100
24.0
14.0
19.0
150
26.0
16.0
21.5
200
28.0
18.0
24.0
250
30.0
20.0
26.5
300
32.0
22.0
29.0
400
36.0
26.0
34.0
500
40.0
30.0
39.0
600
44.0
34.0
44.0
PRACTICAL USE
Based on the chart above, we can choose a current/voltage to carry out a test; and then to define the resistance value
of the load with the equation R=U/I. Then, to get the correct resistance close enough to the chosen value, the following
equation must be used :
Resistances to switch to get couple current/voltage are given on the paragraph «Resistances definition».
