**Appendix A**

Appendix A shows an example of ramp test performed on insulator design CONV, with applied pollution of ESDD 0.42 mg/cm<sup>2</sup> and a fog rate 3 L/hr. Figures A1 and A2 shows the average temperature of the main trunk and top and lower trunk areas during the whole test respectively. Figure A3 shows the total dry-band length computed for the same selected test. Figure A4 shows the dry-band development on each trunk as a maximum temperature profile on a 3D plot versus time and vertical axis position.

**Figure A1.** Average temperature of the main trunk areas during the whole test (left and right zones). Design CONV, ESDD = 0.42 mg/cm2, and a fog rate of 3 L/hr.

**Figure A2.** Average temperature of top and lower trunk areas during the whole test (left and right zones). Design CONV, ESDD = 0.42 mg/cm2, and a fog rate of 3 L/hr.

**Figure A3.** Total dry-band length. Ramp-test: Design CONV, ESDD = 0.42 mg/cm2, and a fog rate of 3 L/hr.

**Figure A4.** 3D representation of dry-band development on each trunk. Ramp-test: Design CONV, ESDD = 0.42 mg/cm2, and a fog rate of 3 L/hr.
