The Tesys LC1D*K** are special contactors for switching 3-phase capacitor banks (category AC-6b according to IEC60947-4-1). They are dedicated only for this purpose and should not be used in other applications. The contactor selection must be based on the kVAR rating and not on the operational current.
However, the operational current for switching 3-phase capacitor banks in AC-6b can be calculated from operational power as follows:
Ie = Q/(√3*U)
where Q = Power in VAR, U = phase-phase voltage in Volts, Ie = current in Amps
Example:
LC1DMK** is recommended for a capacitor bank load of 25kVAR at 400Vac. Thus, at this voltage, the current drawn would be as follows:
Ie = Q/(√3*U) = 25000/(1.732*400) ≈ 36Amps.
However, the operational current for switching 3-phase capacitor banks in AC-6b can be calculated from operational power as follows:
Ie = Q/(√3*U)
where Q = Power in VAR, U = phase-phase voltage in Volts, Ie = current in Amps
Example:
LC1DMK** is recommended for a capacitor bank load of 25kVAR at 400Vac. Thus, at this voltage, the current drawn would be as follows:
Ie = Q/(√3*U) = 25000/(1.732*400) ≈ 36Amps.