To make sure that safety is a main concern, there are 5 key steps. In order to ensure that the model is visually safe, the first step is to perform a Walk-Around Inspection. Next check if the worksite is safe to utilize with a Worksite Assessment. The Function Test is the third step so as to know whether or not the model is working in a safe manner. The 4th thing to consider is Proper Operation, so as to know whether or not the unit is safely working. Lastly, Proper Shutdown must be checked in order to make sure the unit is in a safe place and is capable of shutting down properly.
At the center of the 5 steps and this regulation, there is a machine that lifts heavy weights to impressive heights and stands on a triangular footprint. The main objective is to be able to maintain the telehandler upright, but surely there are risks.
The telehandler's triangular base comprises the two front wheels and the rear-axle pivot point. The back axles usually oscillates, thus the rear wheels are not considered part of the base. The telehandler remains upright as long as the center of gravity of the machinery, that is defined as the point in 3 dimensions around which the weight of the machinery is balanced, stays oriented inside the stability triangle.
When the boom is down, adding a load to the forks at that same time moves the center of gravity down and forward. Raising the load would change the center of gravity upwards and to the rear. At the same time, the stability triangle shrinks when this happens. Thus, the higher you lift a load, the less of a margin for error you have since the stability triangle lessens.
With a stable but small stability triangle, it leaves less room for the center of gravity to move left or right. This wandering action can change the stability triangle, leaving less room for the frame to remain balanced if it is not perfectly level. For example, imagine the center of gravity resembling a plumb bob hanging from the boom. You will always be able to find the center of gravity someplace on a totally vertical line between the center of the ground and a point on the boom. If the frame is not level, the center of gravity would not be oriented over the centerline of the machine. The stability triangle is always aligned with the centerline of the machine.