How to work correct weight out after trip to weigh bridge ?

[Sproket]

This evening I took our Hymer Nova 530 up to the self weigh unit.

Which the police take the wagons to check their axle weight,

As per instructions wait for green light, then proceed at walking pace.

Problem that I'm seeking advice about is the plate on the van says 1 axle 1600kg,

When I went over the platform the weights are displayed on a large digital read out,

Weights with van coupled = truck front axle = 1110kg

Rear axle = 1140kg

Caravan axle = 1540kg

Total weight = 3790kg

Weight with out van = truck front axle = 1160kg

Rear axle = 990kg

Total weight = 2150kg

1st weigh = 3790kg

2nd weigh = 2150kg

caravan = 1640kg ?

The problem I have got is if for some unknown reason I was stopped by the police

And taken to a weigh bridge, that does not do axle weighing would I would be over weight ?

As I see it here the axle weighs 1540kg + 100kg on the nose ??

But on a normal weigh bridge it would show 1640kg ??

I would be very grateful for any answers you have got

Regards

Steve.

 

[Angus1]

I stand to be corrected Steve, but as the axle weight is below that specified by the manufacturer, as long as you are under your MPTLM (i.e if that is greater than 1640 kgs) you are legal.

 

[antrimboy]

From the info I've got, your MTPLM is 1600Kgs.,so in theory, yes you would be overloaded, but, I am led to believe, rightly or wrongly, that if taken to a weighbridge, the only weight that the police are interested in is the Gross Vehicle Weight.

Having said that, I don't think that you would have a leg to stand on in an insurance situation.Additionally, with many caravans now being fitted with movers, heavier batteries, and even air-con units,etc., I'll bet there are a good many caravanners travelling with or without the knowledge of being overloaded.

 

[gary]

I think not, 100kg is less than 5% and having been weighed I know the police allow a discrepancy of 5% because how can anyone be expected to be totally accurate all of the time?.

Life's simply not like that

 

[Oldfogey]

I suggest you speak to the weighing centre and ask for details of their certification, in 2 respects;

1. What weights are they certified to measure, and

2. If they are actually certified to weigh the amounts you are looking at, what is their certified accuracy.

Unfortunately, a lorry weighbridge may be seriously inaccurate for weighing a caravan.

 

[Lutz]

The figures that you give show that the caravan was overweight by 40kg, yes.

One can arrive at this conclusion as follows:

Front axle load of car with caravan hitched up = 1110kg

Rear axle load of car with caravan hitched up = 1140kg

Hence, GVW of car with caravan hitched up = 2250kg

Front axle load of car without caravan hitched up = 1160kg

Rear axle load of car without caravan hitched up = 990kg

Hence, GVW of car without caravan hitched up = 2150kg

Consequently, the noseweight must have been 2250 - 2150 = 100kg

Axle load of caravan = 1540kg

Total weight of caravan = axle load + noseweight = 1640kg

If you had taken the caravan to a weighbridge and weighed it on its own (with the jockey wheel also standing on the weighbridge), the result would also have been 1640kg.

 

[Lutz]

ps: Does the plate on the caravan say that the axle load is 1600kg or does it specify an MTPLM of 1600kg? If 1600kg is the axle load, what does the plate say with respect to MTPLM? Both figures should appear on the plate.

 

[GeorgeB]

Sorry Sproket & Lutz, but there's a fatal flaw in your calculations, you cannot simply add loaded axle weights together to get a vehicle gross weight, the individual loaded axles weights will always add up to more than the permissable max laden weight of the vehicle as each axle will always support more than the theoretical 50% of the vehicle (assuming 2 or more axles).

For example my car, Audi A4 Avant 2litre TDi auto (Audi figures)

Gross Vehicle Weight(GVW) = 2060kg

Kerb side weight = 1585kg

max front axle weight = 1100kg

max rear axle weight = 1090kg

1100kg + 1090kg = 2190kg which exceeds the 2090kg GVW

Simulary the max gross train weight(GTW) of car + trailer (12% gradient & max braked trailer weight at 12% gradient is 1600kg)

is 3705kg.

3705kg - 1600kg = 2105kg which exceeds the 2060kg GVW! confusing eh!

My caravans MTPLM is 1500kg and its max axle weight is also 1500kg, so providing I don't exceed that weight then I'm legal, however nose weight is another issue, 7% of 1500kg is 105kg, but my cars max towball weight is 80kg, & this 80kg is also part of the pemissable load (and rear axle load!) of the car

The only way to correctly establish the weight of a vehicle (car or caravan) is to weigh it with all contact points on the weighing device.

The danger is that you can be legally within the vehicles GVW or GTW but exceed the max laden weight of an individual axle or in the case of a combination of vehicle & trailer be within the GTW but exceed either the GVW or permissable trailer weight or an individual axles weight!

The reason the police prefer to weigh trucks individual axle weights is because with a truck its relatively easy to be loaded within the GVW or GTW but its more diffiult to correctly load each of the axles, plus its a legal requirement for trucks to display the vehicles plated (legally designated) weights.

Hope I haven'tconfused the issue too much!

 

[Lutz]

I wasn't referring to max. GVW in my reply, but to the actual GVW, so there is nothing wrong with my calculation.

I'm sorry, but there's a flaw in your response. If the maximum gross train weight is 3705kg and the maximum GVW of the car is 2060kg, then the car may tow 1645kg, and possibly even more if the car is not fully laden. The 1600kg limit that you quote applies only to a 12% gradient. Therefore, if you are going to limit yourself to towing at less than 12%, you may tow whatever is specified at a less severe gradient.

There is nothing illogical with the sum of the maximum front and rear axle loads of the car being in excess of the maximum permitted GVW.

And you can forget the 7% formula for noseweight. That really an anachronism from the past when owners didn't have anything better to go by and caravans were generally lighter.

 

[antrimboy]

George, going by the figures you have given, you should never end up with a GVW anywhere near 2190 Kgs.

If you have a front axle load of say 1050 Kgs., the max. you could load the rear axle to would be 1010 Kgs. The figures simply indicate the max. load that each individual "axle" is allowed to carry, and certainly doesn't mean that you can load both axles to max. at the same time.

The GTW of a car and caravan is the total load on the number of axles when on a weighbridge, and would equate to the same weight if each axle was weighed individually and then added together.

 

[weejock]

Hi Sproket

On the face of it all your axle weights seem fine. The point that crosses my mind is what are you towing with.

If it is a car or 4x4 check the handbook for the max axle weights allowed. As long as the axle weight of the caravan is within the plated weight the rest of your weight is okay on the towball providing it does not make the rear axle exceed its limit.

However if you are using a comercial vehicle that has room to carry cargo for reward there will be a plate with its weights somewhere on the vehicle.

If this is the case then you must be very careful with your train weights as whilst you may not be overloading them you might then require a tachograph and operators licence.

Also I know that Hymer caravans are continental and would wonder what the width of it is as this may effect the type of vehicle required to drive it.

If you really want to be confused log onto the vosa website and try and go through the multitude permutations of what you can and can't do.

 

[Lutz]

Hi Sproket

On the face of it all your axle weights seem fine. The point that crosses my mind is what are you towing with.

If it is a car or 4x4 check the handbook for the max axle weights allowed. As long as the axle weight of the caravan is within the plated weight the rest of your weight is okay on the towball providing it does not make the rear axle exceed its limit.

However if you are using a comercial vehicle that has room to carry cargo for reward there will be a plate with its weights somewhere on the vehicle.

If this is the case then you must be very careful with your train weights as whilst you may not be overloading them you might then require a tachograph and operators licence.

Also I know that Hymer caravans are continental and would wonder what the width of it is as this may effect the type of vehicle required to drive it.

If you really want to be confused log onto the vosa website and try and go through the multitude permutations of what you can and can't do.

I know what you are hinting at regarding the width of Continental caravans, but a Hobby 530 is street legal in the UK behind an 'normal' car.

 

[mauron]

Hi Sproket,

In 2006 I bought a Dethleffs DL470 and fitted a motor mover.

I took it to my local weighbridge and found that it weighed 50kgs over my exoected weight.

Dethleffs confirmed that the caravan's weight is 50Kg over the brochure weight (due to a printing error). This left me with a payload of only 80kg.

Dethleffs supplied me with a chassis upgrade plate that included the extra 50kg to cover the difference.

If you are not happy can Hymer also not provide an upgrade plate?

I know this is not your original query but hope it helps.

Cheers,

Ron

 

[Sproket]

Hi Sproket,

In 2006 I bought a Dethleffs DL470 and fitted a motor mover.

I took it to my local weighbridge and found that it weighed 50kgs over my exoected weight.

Dethleffs confirmed that the caravan's weight is 50Kg over the brochure weight (due to a printing error). This left me with a payload of only 80kg.

Dethleffs supplied me with a chassis upgrade plate that included the extra 50kg to cover the difference.

If you are not happy can Hymer also not provide an upgrade plate?

I know this is not your original query but hope it helps.

Cheers,

Ron

Thank you all very much for your replies,

The vehicle I am towing with is a ( 3.0 Isuzu Denver Rodeo Auto ),

In the main data and specifications charts it says that my front axle max is 1300kg and rear axle max is 1730kg

It says gross weight of truck = 2900kg

I have managed to find the specifications for my Hymer 530 its 23'3" long x 7'6" wide with a ( MTPLM ) = 1600kg

I have had a Powrtouch Caravan Motor Mover fitted & a new 120amp battery so that reduces my carrying capacity,

that's the reason I took it to weigh it.

I have managed to chuck out the extra 40kg ( I could not believe how easy things added up )

I extra 25mtr roll of hook up cable & 1 of my wheel clamps weighed 20kg !!

I had bought some plastic crates what fold down to put under the fixed beds to stop things rolling about,

They have come out ( 2kg each x 7 ) = 14kg

Its a heavy van all right, my truck has got a back on for our dogs,

So the extra things we will need will be put into a roof box,

It also big enough to fit the awning in if its still wet

Many thanks again

Steve.

 

[Sproket]

Thank you all very much for your replies,

The vehicle I am towing with is a ( 3.0 Isuzu Denver Rodeo Auto ),

In the main data and specifications charts it says that my front axle max is 1300kg and rear axle max is 1730kg

It says gross weight of truck = 2900kg

I have managed to find the specifications for my Hymer 530 its 23'3" long x 7'6" wide with a ( MTPLM ) = 1600kg

I have had a Powrtouch Caravan Motor Mover fitted & a new 120amp battery so that reduces my carrying capacity,

that's the reason I took it to weigh it.

I have managed to chuck out the extra 40kg ( I could not believe how easy things added up )

I extra 25mtr roll of hook up cable & 1 of my wheel clamps weighed 20kg !!

I had bought some plastic crates what fold down to put under the fixed beds to stop things rolling about,

They have come out ( 2kg each x 7 ) = 14kg

Its a heavy van all right, my truck has got a back on for our dogs,

So the extra things we will need will be put into a roof box,

It also big enough to fit the awning in if its still wet

Many thanks again

Steve.