ESSENTIAL TERMINOLOGY AND LEGAL REQUIREMENTS
for weight specifications and tests for caravans and motorhomes

1. Technically permissible maximum laden mass 

The technically permissible maximum laden mass of the vehicle (e.g. 2,000 kg) is a mass specification defined by the manufacturer that the vehicle must not exceed. You can find information on the technically permissible maximum laden mass of the model you have selected in the technical data. Driving the vehicle even if it exceeds the technically permissible maximum laden mass constitutes an administrative offense that may result in a fine.

2. Mass in running order

In simple terms, the mass in running order is the basic vehicle with standard equipment. This essentially includes the following items:

• the unladen weight of the vehicle together with the bodywork, including operating fluids;
• the standard equipment, i.e.  all equipment and standard fittings included when the vehicle leaves the factory;
• the 100% filled water tank or driving tank according to the manufacturer’s specifications and a 100% filled aluminum gas cylinder. 

You can find information on the mass in running order for each model in our sales documents. It is important to note that the value specified in the sales documents for the mass in running order is a standard value determined in the type approval process and verified by the authorities. It is legally permissible and possible for the mass in running order of the vehicle delivered to you to deviate from the nominal value specified in the sales documents. The legally permissible tolerance is ± 5%. This allows EU legislation to account for the occurrence of certain fluctuations in the mass in running order due to weight fluctuations in components supplied by third-party suppliers as well as process and weather-related factors. These weight deviations can be illustrated using the following example calculation:  

• Mass in running order according to sales documents: 1,600 kg
• Legally permissible tolerance of ± 5%: 80 kg
• Legally permissible range of mass in running order: 1,520 kg to 1,680 kg

The specific range of permissible weight deviations can be found in the technical data for each model.
ERIBA makes great efforts to reduce weight variations to the minimum level that is unavoidable for production reasons. Deviations at the upper and lower ends of the range are therefore very rare; however, they cannot be completely ruled out technically, even after carrying out all possible optimization measures. For this reason, ERIBA checks the actual weight of the vehicle and compliance with the permissible tolerance by weighing each vehicle at the end of the line.  

3. Optional equipment and actual mass

According to the legal definition, optional equipment (also including special or additional equipment) includes all optional equipment parts not included with the standard equipment that are fitted to the vehicle under the responsibility of the manufacturer – i.e. at the factory – and can be ordered by the customer (e.g. awning, smooth panel, Alde heating system, oven, etc.). For information on the individual or package weights of the optional equipment that can be ordered, please refer to our sales documents. In this meaning, optional equipment does not include other accessories that are retrofitted by you or your dealer personally after the vehicle has been delivered from the factory. 

The mass of the vehicle in running order (see no. 2 above) and the mass of the optional equipment installed on a specific vehicle at the factory are together referred to as the actual mass. You will find the corresponding information for your vehicle after handover under item 13.2 of the Certificate of Conformity (CoC). Please note that this information also represents a standardized value. Since the mass in running order – as an element of the actual mass – is subject to a legally permissible tolerance of ± 5% (see no. 2), the actual mass may also deviate accordingly from the specified nominal value.  

4. Payload and minimum payload

The installation of optional equipment is also subject to technical and legal limits: It is only permissible to order an amount of optional equipment for installation at the factory that will leave sufficient free weight for baggage and other accessories (i.e. “payload”) without exceeding the technically permissible maximum laden mass. 

The payload is obtained by deducting the mass in running order (nominal value according to sales documents; see no. 2 above) and the mass of the optional equipment from the technically permissible maximum laden mass (see no. 1 above).
 The EU regulations stipulate a fixed minimum payload for caravans that must remain as a minimum for baggage or other accessories not installed at the factory. This minimum payload is calculated as follows:
Minimum payload in kg ≥ 10 * (n + L) 
where “n” = maximum number of sleeping berths and “L” = total length of the vehicle body (without drawbar).

The maximum number of sleeping berths corresponds to the actual configured sleeping berths of the individual vehicle.  
For a caravan with 6 designated sleeping berths and a total length of the vehicle body of 7 m, the minimum payload is calculated as follows: 10 kg * (6 + 7) = 130 kg.

To ensure that the minimum payload is maintained, there is a maximum combination of optional equipment that can be ordered for each vehicle model. In the above example with a minimum payload of 130 kg, the total mass of the optional equipment for a vehicle with 6 designated sleeping berths and a mass in running order of 1,750 kg should not exceed 120 kg: 

It is important to note that this calculation is based on the standard value for the mass in running order specified in the type approval procedure and does not account for permissible weight deviations for the mass in running order (see no. 2 above).
 If the maximum permissible value of 120 kg for the optional equipment is nearly or fully exhausted in this example and the standard value of the mass in running order is applied, it is possible for the minimum payload of 130 kg to be complied with mathematically in the event of an upward weight deviation even if the vehicle has no load capacity. 

Here is another example calculation for a vehicle with 6 sleeping berths whose actual weighed mass in running order is 2% above the nominal value:

To avoid such a situation, ERIBA further reduces the maximum permissible weight of the total optional equipment that can be ordered depending on the specific model. The limitation of optional equipment is intended to ensure that the minimum payload, i.e. the legally prescribed free mass for baggage and retrofitted accessories, is actually available for the load capacity of the vehicles delivered by ERIBA.  

Since the weight of a specific vehicle can only be determined when it is weighed at the end of the line, in very rare cases a situation may arise in which the minimum payload is not guaranteed at the end of the line despite this limitation of optional equipment. In order to guarantee the minimum payload even in these cases, ERIBA will check together with your trading partner and you before delivery of the vehicle whether, for example, the load capacity of your vehicle is to be increased or optional equipment removed.   

5. Effects of tolerances of the mass in running order on the remaining load capacity

Irrespective of the minimum payload, you should bear in mind that unavoidable production-related fluctuations in the mass in running order – both upwards and downwards – have a corresponding effect on the remaining load capacity: If, for example, you order our example vehicle with optional equipment with a total weight of 90 kg, the calculated payload based on the standard value for the mass in running order is 160 kg. The load capacity actually available may deviate upwards or downwards from this value due to tolerances. If the mass of your vehicle in running order is approximately 2% higher than specified in the sales documents, the load capacity is reduced from 160 kg to 125 kg:   

In order to ensure that the calculated payload is actually adhered to, you should therefore take the possible and permissible tolerances for the mass in running order into account as a precaution when configuring your vehicle.
   
We also recommend weighing the loaded caravan on a scale before each journey to check whether the technically permissible total weight is adhered to.  In addition, we recommend checking the actual drawbar load of the loaded vehicle. This must not be higher than the max. drawbar load of the towing vehicle. Furthermore, the technically permissible maximum laden mass of the vehicle combination must be observed when loaded, i.e. the maximum mass of the combination of your motor vehicle and your caravan.overviewovervieweriba-original-parts

1. Technically permissible maximum laden mass 

The technically permissible maximum laden mass of the vehicle (e.g. 3,500 kg) is a mass specification set by the manufacturer which the vehicle must not exceed. Information on the technically permissible maximum laden mass of the model you have chosen can be found in the technical data. If the vehicle exceeds the technically permissible maximum laden mass in everyday driving, this constitutes an administrative offence which may result in a fine.

2. Mass in running order 

In simple terms, the mass in running order is the basic vehicle with standard equipment plus a legally fixed standard weight of 75 kg for the driver. This essentially includes the following items: 

• the unladen weight of the vehicle together with the bodywork, including operating fluids such as greases, oils and coolants; 
• the standard equipment, i.e. all equipment items that are included as standard in the factory-fitted scope of delivery;
• the fresh water tank filled to 100 % in driving mode (driving fill according to manufacturer's specifications; 20 litres) and an aluminium gas cylinder filled to 100 % with a weight of 16 kg;
• the fuel tank, which is 90 % full, including fuel;
• the driver, whose weight – regardless of the actual weight – is generally specified as 75 kg in accordance with EU law.

Information on the mass in running order can be found for each model in our sales documents. It is important to note that the value for mass in running order given in the sales documents is a default value determined in the type-approval procedure and verified by the authorities. It is legally permissible and possible for the mass in running order of the vehicle delivered to you to deviate from the nominal value stated in the sales documents. The legally permissible tolerance is ± 5 %. In this way, the EU legislator accounts for the fact that certain fluctuations in the mass in running order occur due to variations in the weight of supplied parts as well as due to processes and weather conditions. 
These weight deviations can be illustrated by means of an example calculation: 

• Mass in running order acc. to sales documents: 2,850 kg 
• Legally permissible tolerance of ± 5 %: 142.50 kg
• Legally permissible range of mass in running order: 2,707.50 kg to 2,992.50 kg

The specific range of permissible weight deviations can be found for each model in the technical data. ERIBA makes great efforts to reduce weight variations to the minimum that is unavoidable for production reasons. Deviations at the upper and lower end of the range are therefore very rare; however, they cannot be completely ruled out technically, even with all optimisations. The real weight of the vehicle and compliance with the permissible tolerance is therefore checked by ERIBA by weighing each vehicle at the end of the line. 

3. Mass of the passengers 

The mass of the passengers is set a standard value of 75 kg for each seat provided by the manufacturer, regardless of the actual weight of the passengers. The mass of the driver is already included in the mass in running order (see no. 2 above) and is therefore not included again. In the case of a motorhome with four permitted seats, the mass of the passengers is therefore 3 * 75 kg = 225 kg. 

4. Optional equipment and actual mass of the vehicle 

Optional equipment (also: additional equipment) includes, according to the legal definition, all optional equipment parts not included in the standard equipment which are fitted to the vehicle under the responsibility of the manufacturer – i.e. ex works – and can be ordered by the customer (e.g. awning, bicycle or motorbike carrier, satellite system, solar system, oven, etc.). Information on the individual or package weights of the optional equipment that can be ordered can be found in our sales documents. Optional equipment in this sense does not include other accessories that are retrofitted by the dealer or you personally after the vehicle has been delivered ex works. 
The mass of the vehicle in running order (see no. 2 above) and the mass of the optional equipment fitted to a specific vehicle at the factory are together referred to as the actual mass. You will find the corresponding information for your vehicle after handover under item 13.2 of the Certificate of Conformity (CoC). Please note that this specification also represents a standardised value. Since the mass in running order – as an element of the actual mass – is subject to a legally permissible tolerance of ± 5 % (see no. 2), the actual mass may also deviate accordingly from the stated nominal value.

5. Pay-mass and minimum pay-mass 

The installation of optional equipment is also subject to technical and legal limits: Only so much optional equipment can be ordered and fitted at the factory that sufficient free weight remains for baggage and other accessories (“pay-mass”) without exceeding the technically permissible maximum laden mass. The pay-mass is calculated by subtracting the mass in running order (nominal value according to sales documents, see no. 2 above), mass of the optional equipment and the mass of the passengers (see no. 3 above) from the technically permissible maximum laden mass (see no. 1 above). The EU regulations stipulate a fixed minimum pay-mass for motorhomes, which must remain as a minimum for baggage or other non-factory-fitted accessories. This minimum pay-mass is calculated as follows:
Minimum pay-mass in kg ≥ 10 * (n + L)
Where: “n” is the maximum number of passengers plus the driver and “L” is the overall length of the vehicle in metres.
For a motorhome with a length of 6 m and 4 approved seats, the minimum pay-mass is therefore e.g. 10 kg * (4 + 6) = 100 kg.

To ensure that the minimum pay-mass is maintained, there is a maximum combination of optional equipment that can be ordered for each vehicle model. In the above example with a minimum pay-mass of 100 kg, the total mass of optional equipment for a vehicle with four permitted seats and a mass in running order of 2,850 kg should not exceed 325 kg:

It is important to note that this calculation is based on the default value for mass in running order as defined in the type-approval procedure, without taking into account the permissible weight deviations for mass in running order (see no. 2 above). If the maximum permissible value for the optional equipment of (in the example) 325 kg is almost or completely exhausted, an upward weight deviation can therefore result in the minimum pay-mass of 100 kg being met mathematically using the default value for the mass in running order, although in fact there is no corresponding load capacity. Here, too, an example calculation for a vehicle with four seats, whose real weighed mass in running order is 2 % above the nominal value:

In order to avoid such a situation, ERIBA further reduces the maximum permissible weight of the total optional equipment that can be ordered on a model-specific basis. The limitation of optional equipment is intended to ensure that the minimum pay-mass, i.e. the legally prescribed free mass for baggage and retrofitted accessories, is actually available for the vehicle load capacity of the vehicles delivered by ERIBA. 
Since the weight of a specific vehicle can only be determined when it is weighed at the end of the line, in very rare cases a situation may arise in which the minimum pay-mass at the end of the line is not guaranteed, despite this limitation of optional equipment. In order to guarantee the minimum pay-mass even in these cases, ERIBA will check together with your trade partner and you before delivery of the vehicle whether, for example, the vehicle is loaded up, seats are reduced or optional equipment is removed. 

6. Effects of tolerances of the mass in running order on the pay-mass 

Regardless of the minimum pay-mass, you should note that unavoidable production-related fluctuations in the mass in running order – both upwards and downwards – have a mirror-image effect on the remaining load capacity: If you order our example vehicle (see no. 3. above), for example, with optional equipment with a total weight of 150 kg, the calculated pay-mass based on the default value for the mass in running order is 275 kg. The load capacity actually available may deviate from this value due to tolerances and may be higher or lower. If the mass in running order of your vehicle is, for example, permissibly 2 % higher than stated in the sales documents, the load capacity is reduced from 275 kg to 218 kg:

As a precaution to ensure that the calculated pay-mass is actually given, you should therefore take the possible and permissible tolerances for the mass in running order into account when configuring your vehicle.
We also recommend that you weigh the laden motorhome on a non-automatic scale before each journey and, taking the individual weight of the passengers into account, determine whether the technically permissible maximum laden mass and the technically permissible maximum mass on the axle are observed.