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1.6 Working principle
The principle block diagram of this soft starter is shown as in Fig. 2. The power part is composed of three pairs of anti-
parallel thyristors as shown in Figure 1. The core microprocessor of the control part collects the synchronization signal,
voltage signal, current signal and motor power factor angle of the power grid. The control software changes according to
these four parameters. Using the thyristor phase shift technology, the voltage applied to the motor slowly reaches the full
voltage according to a certain rule. By setting the control parameters appropriately, the torque and current of the motor can
be better matched with the load requirements.
Fig.1
Thyristor power module
Fig.2
principle block diagram
1.7 Incoming inspection
⚫
Before taking the soft starter out of its packaging materials, please make sure that the packaging carton has not been
damaged during transportation. Damage to packaging cartons is usually caused by improper transportation. If you
find any damage, please notify the carrier and your dealer representative.
⚫
Please confirm that the nameplate and label of the soft starter conform to the packing list and the corresponding
purchase order. If the soft starter is not installed immediately, it should be stored in a clean and dry area with an
ambient temperature of -25°C~+70°C.
