HT instruments HT78 - Manual (Page 12)

HT78
EN - 11
4.3.3. Leakage current measurement on Three phase system
CAUTION
Do not perform any AC current measurement on circuit with nominal voltage
higher to 500V to round to avoid possible electrical shocks and to damage
the meter
Fig. 5: Taking leakage current measurement on Three phase systems
1. Select the 300mA range on the meter
2. Move the FILTER selector on ON position to activate the “Low-pass 150Hz filter” (see §
4.2.3)
3. Open the clamp and put inside:
¾ The cables L1, L2, L3 and N if use the Differential methos as shown in Fig. 5
obtaining the result as addition of instantaneous values of the currents flowing in the
wires
¾ The PE conductor if use the Direct method
4. The measured result is shown at display
5. For using of Data HOLD and see § 4.2.2. For using of analogical output see § 4.2.6