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Table 1: HF lighting load harmonics summary –
case study 1
Voltage (V) Current (A)
RMS 245·1 65·39
Peak 336·5 158·08
DC offset -0·4 -0·35
Crest 1·37 2·42
THD% rms 5·98 43·54
THD% fund 5·99 48·37
Hrms 14·7 28·42
K factor 8·77  
Table 2: Communications room distribution board current and distortion – case study 2
Red Yellow Blue
Current (A rms) 24 41 53
THD (% fundamental) 50 40 31
Voltage (V rms) 237 238 237
THD (% fundamental) 8 8 8·26