ABB TB820-2V2 After sales service is provided for the control card of the power supply device

Description

Packaging details: if you need an urgent delivery order, please feel free to contact us, and we will do our best to meet your needs.

Price problem: if you find that other suppliers offer cheaper prices for the same product, we are also willing to provide you with reference prices and give you further discounts.

• IEC 60204-1”Safety of machinery – Electrical equipment of machines – General
requirements” Clause 13.5 recommends that: “the voltage drop from the point
of supply to the load shall not exceed 5% of the rated voltage under normal
operating conditions”.
• IEC 60364-7-714 “Electrical installations of buildings – Requirements for
special installations or locations – External lighting installations” Clause 714.512
requires that “the voltage drop in normal service shall be compatible with the
conditions arising from the starting current of the lamps”.
Voltage drop calculation
For an electrical conductor with impedance Z, the voltage drop is calculated
by the following formula:
where
• k is a coefficient equal to:
– 2 for single-phase and two-phase systems;
– for three-phase systems;
• Ib [A] is the load current; if no information are available, the cable carrying
capacity Iz
shall be considered;
• L [km] is the length of the conductor;
• n is the number of conductors in parallel per phase;
• r [Ω/km] is the resistance of the single cable per kilometre;
• x [Ω/km] is the reactance of the single cable per kilometre;
• cosϕ is the power factor of the load:
Normally, the percentage value in relation to the rated value Ur
is calculated
by:
Resistance and reactance values per unit of length are set out on the following
table by cross-sectional area and cable formation, for 50 Hz; in case of 60 Hz,
the reactance value shall be multiplied by 1.2.