I. Power Distribution System Framework
The installation of the asphalt mixing plant's circuit begins with the design of the power distribution system, much like planning the load-bearing structure before building a house. The main circuit adopts a three-level power distribution mode: the high-voltage incoming cabinet handles the power input, the transformer performs voltage conversion, and the low-voltage distribution cabinet distributes power to various functional areas. A key point is to reserve a 20% margin when calculating the total load to cope with the instantaneous current surge during motor startup. Cable laying should preferably use cable trays, which facilitates maintenance and effectively isolates heat sources.

II. The Nerve Network of the Control Circuit
The control circuit is the intelligent central hub of the mixing plant, employing a hybrid control scheme of PLC + relay. Temperature sensors monitor the asphalt heating status in real time, converting the signal into a 4-20mA current for transmission; the weighing module collects aggregate data through strain gauges, with an accuracy of ±0.5%. Special attention must be paid to ensuring that the motor control circuit has a mechanical interlock to prevent simultaneous engagement of the forward and reverse contactors. The control panel buttons use a safe 24V voltage, and the strong and weak current lines in the control cabinet must maintain a distance of at least 15cm.
III. Invisible Armor for Safety Protection The safety system includes a triple protection mechanism: the leakage current circuit breaker trips immediately upon detecting a leakage current exceeding 30mA; the thermal relay cuts off the power within 0.5 seconds in case of motor overload; and the emergency stop button features a red mushroom-shaped design and is connected in series with all control circuits. The lightning protection grounding resistance must be less than 4Ω, and both ends of the cable's metal sheath must be reliably grounded. The desiccant box should be installed at the bottom of the electrical cabinet, and the heating dehumidification device should automatically activate when the humidity exceeds 60%.