Voltage, Measured Limiting (MLV) : Maximum magnitude of voltage that is measured across the terminals of the surge protective device (SPD) during the application of impulses of specified waveshape and amplitude
NFPA 780 Standard for the Installation of Lightning Protection Systems, 2008 ed. http://www.uscg.mil/Petaluma/TPF/ET_SMS/Manuals/NF PA_780.pdf, (Std: Instll of Lightning Prot Sys - Amer) {347 NFC}