TARE – Weight of trailer only, unladen
Aggregate Trailer Mass (ATM) – Total weight of trailer, including cargo and ball weight
Gross Trailer Mass (GTM) – Load carried over the trailer axles
Firstly, the TARE weight must be obtained by weighing the trailer to determine weight at axles and weight at ball.
The sum of axle and ball weight with the trailer empty is the TARE weight.
The maximum ATM rating for the Tandem Axle Box trailer plan is 2400kg.
The maximum GTM rating would be the ATM minus the ball weight at TARE.
For example, if the ball weight at TARE was measured to be 80kg, the GTM would be calculated as follows:
GTM = ATM – 80kg = 2400 – 80 = 2320kg
The weight ratings of equipment such as the sum of wheels/tyres, coupling, chains, axle/suspension must be taken into account.
The ATM rating cannot exceed the rating of equipment such as coupling, chains and plan specifications. The GTM rating cannot exceed the rating of the sum of wheels/tyres, or rating of axle/suspension.