Is a battery required and what is the other problem?

[Surfer]

The caravan is connected up to MHU (Mains) but if the 12v switch is flicked off everything seems to shut down including the fridge which is on 220v and the 220v lights.

I have been assured by two other Baileys owners on site that a Bailey caravan will not work without a battery in place which to me sounds very strange. I am assuming that there is a switch somewhere in the caravan that should allow the 12v circuit to operate without a battery in place.

The caravan in question has a good battery and has reading on a multi meter of 12.5+ volts, but if the battery is removed everything shuts down including the 220v. With the battery in place the lights go dim and then bright, then dim and so forth. It is a Bailey Vendee 2003 caravan.

My view is that if the caravan cannot operate correctly without a battery in place the dealer is selling you sub standard goods. After all if you purchased a car and it had no battery, would you accept it?

Can any one offer any advice on the problem with the lights pulsating and also whether the caravan can operate without a battery? Thanks.

 

[ProfJohnL]

Hello Ian,

I am not specifically familiar with the equipment fitted to the Bailey caravans so I can't comment on your specific problems in detail. Whether or not a caravan can be run with or without a battery in circuit is dependant on the design of the system. Your handbook should tell you. If you do not have a handbook, then contact either your dealer or the manufacture to obtain one.

However in general most 2003 caravans should will fitted with power supply which can provide a reasonable number of amps current at 13.8V (the nominal out put for 12v circuits in caravans), and it should be possible to run the essential 12V components in the caravan without a battery. (lights, water pump, blown hot air system and water heater). Any thing else may be over-loading the supply fitted to the caravan.

The pulsing of the lights suggests that there may be a problem with the Power supply unit., and certainly mains powered equipment should not need to have 12V available to operate. Both symptoms suggest there is some fault in the caravans wiring, and for you and your families' safety I strongly recommend you have the caravan checked by a competent electrician who will be able to diagnose and recommend a proper course of action.

Further to your question about the fitting of the battery at the point of sale, I would tend to agree that if it is an 'essential' feature that the caravan needs a battery to operate, then it should feature as a standard item, but in most cases (for my reasons above,) it is not essential, so it does not normally form part of the standard OEM equipment supplied by the manufacturer.

Many dealers, who actually sell the caravan, may include a battery as part of the sales package, but that has nothing to do with the manufacturer.

 

[Willy_5041515]

It is possible that the 12 volt circuits are designed not work without the battery. This is to protect 12 volt devices such as lights, pumps, etc., from being connected directly to the 12 volt charger without the "smoothing" effect of the battery. The charger, without battery, may well put out voltage spikes which could damage these circuits. Modern chargers use switched mode technology (instead of heavy transformers) which tend to do this, so your caravan may be wired to prevent the 12 volt circuits from operating without a battery connected. The pulsing of the lights, with the battery connected and assuming it's not severe, is almost certainly due to the charger automatically switching to full charge mode, sensing that the battery is already fully charged and then switching back to standby charge mode. This would cause a difference in output of up to 2 volts, which would be noticeable on lighting circuits.

 

[Rita1]

I thought all Caravans had to have a battery connected even when on EHU As the 12volt system is worked through the charger/battery for the Lights /pump

So no battery no lights

Are you sure your lights are 240v

Rita

 

[TrevorM]

I do not know the answers to your questions, but John L's response looks to have covered it well (as always!)

On my own (1998) 'van, the on board charger can, in the absence of a battery act as a power supply, with a maximum output of 10Amps. I know this because I have just replaced the Zig unit. After a bit of research, looking at 'intelligent' chargers etc., I decided to replace with another Zig, but only because it meant I could do the job with a minimum of effort (same fixings and cabling.)

There are superior chargers out there, but SOME of these will NOT act as a power supply UNLESS there is a battery connected. If your charger is not faulty, it is possible your 'van may have been fitted with this type of device.

As John suggests, the mains problem needs proper investigation.

Enjoy your hols

Trevor M