SLLA563 June   2021 ISO1042 , ISO1042-Q1 , ISO1044 , ISO1050 , ISO1176 , ISO1176T , ISO1410 , ISO1412 , ISO1430 , ISO1432 , ISO1450 , ISO1452 , ISO15 , ISO1500 , ISO1540 , ISO1540-Q1 , ISO1541 , ISO1541-Q1 , ISO1640 , ISO1640-Q1 , ISO1641 , ISO3080 , ISO3082 , ISO3086 , ISO3086T , ISO3088 , ISO35 , ISO35T , ISO6720 , ISO6720-Q1 , ISO6721 , ISO6721-Q1 , ISO6731 , ISO6731-Q1 , ISO6740 , ISO6740-Q1 , ISO6741 , ISO6741-Q1 , ISO6742 , ISO6742-Q1 , ISO7021 , ISO7041 , ISO7131CC , ISO7140CC , ISO7140FCC , ISO7141CC , ISO7141FCC , ISO7142CC , ISO7142CC-Q1 , ISO721 , ISO721-Q1 , ISO721M , ISO721M-EP , ISO722 , ISO722-Q1 , ISO7220A , ISO7220A-Q1 , ISO7220B , ISO7220C , ISO7220M , ISO7221A , ISO7221A-Q1 , ISO7221B , ISO7221C , ISO7221C-HT , ISO7221C-Q1 , ISO7221M , ISO722M , ISO7230C , ISO7230M , ISO7231C , ISO7231C-Q1 , ISO7231M , ISO7240C , ISO7240CF , ISO7240CF-Q1 , ISO7240M , ISO7241A-EP , ISO7241C , ISO7241C-Q1 , ISO7241M , ISO7242C , ISO7242C-Q1 , ISO7242M , ISO7310-Q1 , ISO7310C , ISO7310FC , ISO7320-Q1 , ISO7320C , ISO7320FC , ISO7321-Q1 , ISO7321C , ISO7321FC , ISO7330-Q1 , ISO7330C , ISO7330FC , ISO7331-Q1 , ISO7331C , ISO7331FC , ISO7340-Q1 , ISO7340C , ISO7340FC , ISO7341-Q1 , ISO7341C , ISO7341FC , ISO7342-Q1 , ISO7342C , ISO7342FC , ISO7420 , ISO7420E , ISO7420FCC , ISO7420FE , ISO7420M , ISO7421 , ISO7421-EP , ISO7421A-Q1 , ISO7421E , ISO7421E-Q1 , ISO7421FE , ISO7520C , ISO7521C , ISO7631FC , ISO7631FM , ISO7640FM , ISO7641FC , ISO7641FM , ISO7710 , ISO7710-Q1 , ISO7720 , ISO7720-Q1 , ISO7721 , ISO7721-Q1 , ISO7730 , ISO7730-Q1 , ISO7731 , ISO7731-Q1 , ISO7740 , ISO7740-Q1 , ISO7741 , ISO7741-Q1 , ISO7741E-Q1 , ISO7742 , ISO7742-Q1 , ISO7760 , ISO7760-Q1 , ISO7761 , ISO7761-Q1 , ISO7762 , ISO7762-Q1 , ISO7763 , ISO7763-Q1 , ISO7810 , ISO7820 , ISO7820LL , ISO7821 , ISO7821LL , ISO7821LLS , ISO7830 , ISO7831 , ISO7840 , ISO7841 , ISO7842 , ISOW1044 , ISOW1412 , ISOW1432 , ISOW7740 , ISOW7741 , ISOW7742 , ISOW7743 , ISOW7744 , ISOW7821 , ISOW7840 , ISOW7841 , ISOW7841A-Q1 , ISOW7842 , ISOW7843 , ISOW7844

 

  1.   Trademarks
  2. 1Introduction
  3. 2Solid Insulation
  4. 3Why International Standards for High Voltage Components Have Minimum DTI Requirements
  5. 4Quality of Insulation Materials
  6. 5Various IEC Standards and their DTI Requirements
    1. 5.1 IEC 60747-17
    2. 5.2 UL 1577
    3. 5.3 IEC 62368-1
    4. 5.4 IEC 60601-1
    5. 5.5 IEC 61010-1
  7. 6Conclusion
  8. 7References

IEC 61010-1

IEC 61010-1 Edition 3 is an international standard that has general safety requirements for electrical equipment for measurement, control, and laboratory use. Creepage and clearance distance requirements for mains circuits of overvoltage category II up to 300 V (RMS or DC) are provided in clause 6.7.2.1 (Table 4 of IEC 61010-1). For voltages above 300 V of overvoltage category II, we’ll refer to Table K.2 of the standard. Table 5-4 is the partial representation of Table K.2 of IEC 61010-1.

Table 5-4 Clearances and Creepage Distances for Mains Circuits of Overvoltage Category II above 300 V
Voltage Line-to-Neutral AC RMS or DC Values for Clearance Values for Creepage Distance
Other Insulating Material
Pollution Degree 2
Material Group I Material Group II Material Group III
V mm mm mm mm
> 300 ≤ 600 3.0 3.0 4.3 6.0
> 600 ≤ 1000 5.5 5.5 7.2 10.0

Note that the creepage distance values shown in the table above are for basic insulation. For reinforced insulation, the creepage distance values must be doubled. So, based on this table, our semiconductor component example with minimum 8 mm creepage and clearance distances and material group I can claim up to 600 V (RMS or DC) for reinforced insulation and 1000 V (RMS or DC) for basic insulation.

Next, we turn to DTI requirements for solid insulation. Clause 6.7.2.2.2 and Table K.9 of IEC 61010-1 require a minimum DTI of 0.4 mm, 0.6 mm, or 1 mm for RMS or DC working voltages of up to 300 V, 600 V, and 1000 V respectively. So, based on these DTI requirements, it would seem that semiconductor components with thin dielectric might not be certified to this standard but what most observers do not realize that clause 14.1a of the standard allows applicable safety requirements of a relevant IEC standard, such as IEC 62368-1, to bypass the minimum DTI requirements of this standard. Since IEC 62368-1 allows thermal cycling and humidity preconditioning tests followed by dielectric test with 60% margin to bypass the minimum DTI requirements, the same is allowed for IEC 61010-1 according to clause 14.1a.

To determine test voltage after thermal cycling and humidity preconditioning tests, we turn to clause 6.7.2.2.1 of the standard for working voltages up to 300 V and Table K.5 for voltages between 300 V and 1000 V for overvoltage category II. Table K.5 of IEC 61010-1 is represented by Table 5-5.

Table 5-5 Test voltages for Solid Insulation in Mains Circuits of Overvoltage Category II above 300 V
Voltage Line-to-Neutral AC RMS or DC (V) Test voltage
5s AC Test (VRMS) Impulse Test (VPEAK)
Basic and Supplementary Insulation Reinforced Insulation Basic and Supplementary Insulation Reinforced Insulation
> 300 ≤ 600 2210 3510 4000 6400
> 600 ≤ 1000 3310 5400 6000 9600

As already determined, the example device can claim 600-V reinforced insulation and 1000-V basic insulation working voltage based on creepage and clearance distances, thereafter we need to multiply the respective AC test voltage or impulse test voltage of Table 5-5 by 1.6 and then claim the corresponding working voltages if the component passes the test.