WEG CFW-11W, Дополнение

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Installation and Connection
CFW11W | 2-8
DANGER !
The water temperature must always be higher or equal to the dew point.
DANGER !
Vérifiez que l'alimentation secteur est débranchée avant de commencer l'installation..
ATTENTION
!
The CFW-11W can be connected to circuits with short-circuit capacity of up to 150000
symmetric Arms (maximum 480 V/690 V).
ATTENTION
!
The short-circuit protection of the inverter does not provide short-circuit protection for the
power supply circuit. The short-circuit protection of the power supply circuit must be provided
in accordance with applicable local standards.
2.5.1. Input Rectifier
The main rectifier bridge is selected to comply with the nominal power of the drive. The heat dissipation caused
by losses at the rectifier bridge should be taken into account for the sizing of the heatsink, as well as in the
heating up of the panel internal air.
The resistors of the pre-charge circuit must be dimensioned according to the following criteria:
Maximum voltage
Maximum energy
Power overload capacity of the resistors during the pre-charge period (energy dissipation capacity)
Table 2.5: Dimensioning of the pre-charge
Peak current during pre-charge (A) 0.82 (Vline/R)
Energy stored in the capacitor bank (J)
Line 400 V N∙0.008∙Vline 2
Line 600 V N∙0.004∙Vline 2
Duration of the pre-charge (s)
Line 400 V 0.02∙N∙R.
Line 600 V 0.01∙N∙R.
Where R is the ohmic value of the resistor used in each phase and N is the number of power units. Example:
In a drive composed of three power units, whose line voltage at the rectifier input is 380 Vrms (Line 400 V), the
obtained values would be:
Energy stored in the capacitor bank: 3 ∙ 0.008 ∙ 380
2
= 3466 J.
Using 3 resistors of 10 Ω (one per phase), each resistor must withstand 1155 J.
The manufacturer of the resistor informs the energy the component withstands.
The peak current during pre-charge would be 31 A and the duration of the pre-charge would be 0.6 s.