Split Charge Relay Clicking in and Out

[BongoMTBer]

Anyone else have this?

When I first start my bongo in the morning, it is delivering 14v + to the leaisure battery. However, when I put the air con on, the voltage drop seems to be sufficient for the split charge relay to drop out. This then carries on cycling whilst the air con is on (I guess as the compressor kicks in and out).

Not had any problems with a flat battery as yet, but has anyone else had this prior to an alternator or battery giving up?

I have checked the alternator output with everything off, engine running and battery disconnected, and it is approx 14.4v. It just seems like it cannot keep up with the current demands of the air con system.

[BongoMTBer]

Oh, and I did a search and noticed that Kirsty had something similar last summer. Did you resolve it Kirsty or just end up living with it?

Cheers.

Sam.

[sparkymik]

Oh, and I did a search and noticed that Kirsty had something similar last summer. Did you resolve it Kirsty or just end up living with it?

Cheers.

Sam.

Kirsty is away on holiday at the mo'

Sparky

[waycar8]

is the leisure battery totally flat?, it could be trying to draw too much current if it is?

[BongoMTBer]

is the leisure battery totally flat?, it could be trying to draw too much current if it is?

No, pretty full. Only drawing 4 amps when charging.

Cheers.

[scarlet]

it sounds as if the revs could be dropping when the aircon kicks in so the altenater output is dropping below the 14v for the split-relay to kick in, does this happen only on tick over?

[dandywarhol]

Mine is similar - yet to sort it out but might be looking at fitting a new diode pack (if they're available) in the alternator. Happened last year in europe when using a/c and had a coolbox drawing from the LB

[BongoMTBer]

it sounds as if the revs could be dropping when the aircon kicks in so the altenater output is dropping below the 14v for the split-relay to kick in, does this happen only on tick over?

It happens unless revs are well over 2000 rpm. I know what you mean about the revs dropping which is why I spent yester evening getting the idle boost to work again.... but it aint that. Cheers.

Mine is similar - yet to sort it out but might be looking at fitting a new diode pack (if they're available) in the alternator. Happened last year in europe when using a/c and had a coolbox drawing from the LB

Exactly the same as mine. It is more noticeable when I am using the coolbox.

Have you looked into diode packs much yet?

Also noticed that the regulated voltage seems to fall under load from 14+ volts down to about 13.8v as everything warms up (Have a volt meter and ammeter fitted to the leisure battery).

[g8dhe]

Have you checked that there is no corrosion / dirt on the battery connectors to the main S/B or on 100A fuse that the alternator feeds the batteries, which is mounted on the battery connector itself ?

[dreamwarrioruk]

what split charge are you using. i have a potentiometer in mine so i can adjust the cut off voltage to accound for the drop in output from the alternator

[BongoMTBer]

Have you checked that there is no corrosion / dirt on the battery connectors to the main S/B or on 100A fuse that the alternator feeds the batteries, which is mounted on the battery connector itself ?

Thanks for that. I had checked and all connections look great.

what split charge are you using. i have a potentiometer in mine so i can adjust the cut off voltage to accound for the drop in output from the alternator

Not sure what make but iirc it does have a hole in the front that could well be a pot.

I monitored the voltage again this eve when driving for around 40 mins. After initially stabilising after a few minutes at 14.2 volts, by the end of the journey the voltage was regulating to 13.8 with no aircon on and just the radio. When I got back, I switched on the air con with front and rear blowers on full and the voltage started to decay until relay cut out at about 13.5 v.

I switched the aircon off and it clicked back in and the voltage rose and stabilised at 13.8.

I am guessing that this discrepancy in voltage has something to do with heat build up. I know an increase in heat will increase internal resistance in a conductor, so maybe there is an issue starting to develop with the alternator.

Bottom line is, is this really a problem, or am I just expecting too much from my alternator?

If anyone else fancies putting their aircon and front and rear blowers on full to see if they get the same, I would be most interested in the results.

Did I mention I have OCD?

[mikeonb4c]

Did I mention I have OCD?

Oh we've all got that on here mate.....especially me

Alternator figures sound roughly in range from the figures reported on a thread Haydn Callow ran a day or two back. Dreamwarriors point is an excellent one - I remember I had to adjust my VSR pot. (whilst checking with a voltmeter I think, but it was so long ago) until things clicked on and off properly. I doubt you've got much to lose playing about with it. It certainly sounds like the threshold is currently set a bit high

[BongoMTBer]

Cheers, I shall play!

[BongoMTBer]

Mike, I don't suppose you still have the instructions for setting up your VSR do you? I have had a play with the pot, but not entirley sure wheter it moves the upper and/or lower set points or changes the histeresis?

I would like to see what instructions say.

[mikeonb4c]

Mike, I don't suppose you still have the instructions for setting up your VSR do you? I have had a play with the pot, but not entirley sure wheter it moves the upper and/or lower set points or changes the histeresis?

I would like to see what instructions say.

I'll have a look and get back to you if I find them. PM me with a reminder if I haven't got back to you by the weekend