Help with clicking noise under drivers seat

[Sebnev]

Hi all. Looking for help on identifying/fixing this issue.

When pulling away from stopped sometimes (there doesn’t seem to be an obvious set of circumstances) I can hear a clicking noise coming from under the drivers seat. All I can see under the drivers seat is the leisure battery and the split charge box (as per picture).

The clicking noise could also sound a bit like a solenoid going back and forth. The noise lasts for 1 – 2 seconds and then stops. Yesterday it happened 5 or 6 times in a mile but not again on the way back through same stop/start roadworks. Then a few times later in the day.

This isn’t impacting the drive at all, or the start stop function, but it didn’t do it before so I’d like to find out what it is and fix it !

Any ideas ? Thanks

 

[Loz]

My guess would be that VSR is reacting to the voltage drop caused by the BlueMotion feature of the alternator going idle as it stops generating.

 

[Pauly]

That relay is not really ideal for a vehicle with a smart alternator
A VSR has a set voltage threshold to turn on and off (the clicking you are hearing)
As you have a smart alternator the voltage from your alternator to your engine battery will be going up and down and you drive and brake etc, this will cause the split charge relay to go on and off as the voltage changes

 

[Sebnev]

Thanks both. I suppose my immediate concern is that I've had the van 2 years with the same setup and this noise hasn't happened before - so what could have changed recently. Could the VSR developed a fault, and the clicking is an indication of that ?

But I appreciate the information about the setup isn't ideal - everyday is a learning day (my electric knowledge is very low). Would swapping the VSR for something like a Victron charger controller be more appropriate ?

 

[Pauly]

A DC-DC charger of any style would be better than a VSR but is not a requirement, what you have will work (just not very efficiently as theoretically will never charge the battery above 80%)
Not sure why you have never heard it before as it must have been going on and off as voltage goes up and down, i wonder if the relay has got louder over time or perhaps your engine battery has deteriorated over time and affected the alternator voltage, hard to say really

 

[Sebnev]

When you say it will never charge the battery above 80%, would that also be true if charged via EHU, or does the VSR only count when charging from the alternator ?

In any regards I will test the leisure battery and see what condition its in.
Thanks

 

[Pauly]

Only when charging from emgine/alternator
Your vehicle is set to only charge the engine battery to approx 80% to allow for regenerative braking etc (all part of the efficiencyprogram/bluemotion), when the van batt is satisfied it will ramp down the alternator to decrease load on the engine and increase fuel efficiency, as your leisure battery is effectively coupled onto it then it will charge to approx the same capacity

 

[Pauly]

If your power consumption from your leisure battery is moderate then there is no problem with this and it can work fine for some people but if you are running, for example, a full camper conversion and often parking for prolonged periods without running the engine then you need all the capacity you can get

 

[Sebnev]

Great - thanks for the help