Low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. Electrical safety. Equipment for testing, measuring or monitoring of protective measures. Part 7. Phase sequence
State system for ensuring the uniformity of measurements. Means of measuring spectral density of radiance, spectral density of radiant intensity and spectral density of irradiance in the wavelength range of 0,2-25,0 mkm. Verification procedure