The legislation introduction covering cane move into sugar mills has guided to a raise in the hauliers delivering cane number to Maidstone mill. To ensure fair access to the mill, in ratio to the tonnage of haulier's cane, and to evade congestion at the weighbridge it was determined to establish a system of traffic light controlled by a PLC (programmable logic controller) to control traffic flow across the weighbridge. Every main haulier has a kept lane in the area of queuing for the weighbridge, as well as kept lanes in the area of hilo staging. When a hilo appears at the mill it goes into the area of staging and remains its turn at the particular haulier's queue back. Only if the haulier queue of weighbridge in question has fewer than two hilos in it, which is simply observed by the driver on penetrating the main gate of millyard.
The traffic control system operation is best described by explaining the events sequence from the time a spiller crane of hilo is left to the time the next hilo enters at the tandem in question. Think the operation simple case on the diffuser only:
1. A hilo has completed pulls out and spilling the bay of unloading.
2. The front hilo in the queue of disperser pulls into the bay of unloading.
3. The second hilo in the queue of diffuser shifts in front position.
4. The hilo movement from the second mark reasons of the photocell to release and transmits a signal to the PLC which the diffuser needs a load.
5. The PLC appears for the subsequently haulier in the sequence of pre-programmed and turns on the suitable light on the staging and on the area of weighbridge. The PLC also turns on the light at the way out of the weighbridge representing to the driver that he has to go to the diffuser.
6. Presumptuous that a hilo is coming up in the lane of haulier's queueing, this hilo will drag onto the weighbridge of gross.
7. Once the hilo is on the weighbridge the clerk presses his button of STOP. The light of STOP at the exit of weighbridge is turned on and the PLC turns off the call light to prevent the next queue of hilo in the thoughts he has been called.
8. In reaction to the light of call at the area of staging the next hilo should go into the weighbridge queue as the second hilo in the queue of weighbridge transports to the front.
9. Once considering is complete the clerk of weighbridge presses the button of GO on his panel. The light of STOP is turned off and the GO light on.
10. Once the hilo lands in front of the photocell at the diffuser the cycle is partial.