Effect of Cable Length on Variable Frequency Drive
Every cable has, apart from its resistance, certain inductance and capacitance. The inductance and capacitance is roughly equally distributed along the cable length. Inductance L and capacitance C in a circuit create a resonance.
[caption id="attachment_18636" align="aligncenter" width="600"]
Equivalent Circuit of Long Cable[/caption]
The formula for cable resonance is
[pmath size=20]omega_res=1/{l*sqrt{LC}}[/pmath]
Where:
ω =...
Equivalent Circuit of Long Cable[/caption]
The formula for cable resonance is
[pmath size=20]omega_res=1/{l*sqrt{LC}}[/pmath]
Where:
ω =... 
PEC, NEC and IEC Comparison of Cable sizes
Administrative Order of 1987
The Philippine Electrical Code (PEC) is based on the National Electrical Code (NFPA 70) with a major update on changing the Imperial Units to Metric Units in compliance to the Administrative Code of 1987, the metric system of weights and measures shall be used in the Philippines for all products, articles, goods, commodities, materials, merchandise,...
Key Differences in Power Transformer Selection According to International Standards
Power transformer sizing standards according to IEEE (Institute of Electrical and Electronics Engineers) and IEC (International Electrotechnical Commission) differ in certain key aspects. Here's a breakdown of the major differences between the two:
1. Transformer Rating and Loading
IEEE standards, particularly IEEE C57.12.00, typically provide guidelines for transformer ratings based on ambient temperature and loading conditions in North America. IEEE...
IEC Current Transformer Accuracy Class
Current transformer (CT) accuracy class refers to how precisely a current transformer can replicate the primary current in its secondary winding, within certain tolerances, under defined conditions. CT accuracy is crucial because any deviation in the secondary current can impact the performance of metering devices and protection systems, leading to incorrect readings or faulty operation of protective relays.
Factors Affecting...
