Optimate Start battery charging

[StratosFearXX]

So my starter battery got a bit low so I plugged the Optimate smart charger in, positive to battery positive, negative to body side of the shunt. It charges fine but then errors when it's checking battery condition.

Is the shunt (or the van electrics) interrupting the charging when it gets to 80% or something? Even when the van is locked up and powered down?

 

[Dellmassive]

What error?

After how long?

What model charger?

A few pics will help

 

[StratosFearXX]

Optimate 5 Start Stop OptiMate 5 Start/Stop

Red light comes on solid, not flashing, mannual says this!

6. LED #6 flashing / blinking - BATTERY is not holding charge.
If the red LED #6 lights a significant problem exists. The battery’s voltage is not being
sustained above 12.2V (equal to 50% charge in a standard wet cell battery) or could not be
sufficiently recovered. In the case of a battery still connected to the electrical system it
supports, the red LED #6 may be signalling a loss of current through connected wiring or
'always on' current-consuming accessories. A sudden load such as vehicle headlights being
switched on while the charger is connected can also cause the battery voltage to dip
significantly. The OptiMate will try recharge the battery again and then repeat the health test as described in point 5 above.

Not sure how long it takes to get to that point, will put it on again today and check.

Cheers

 

[Dellmassive]

Hmmm.. that's only a 4A charger.

Which is very low power.

That will take days to charge a flat starter battery..

I'd recommend selling that on eBay and buying a more modern charger in the 10 to 20A range.

 

[Dellmassive]

Have a look at these...

Thread 'Battery Chargers - How I Did It -'

7 Feb 2019

Battery Chargers - How I Did It -


So its that time of year again, cold, rainy. . . . . . . flat battery =[


This time we look at Battery Chargers.

Our vans will most likely come with a AGM style starter battery, for this type of battery we need a "Smart Charger" . . . . but what does this mean?

well, chargers of old were of the constant voltage constant current type affair.


They would put out 13.8v at say 5amps and that was it . . . . . . . .


Modern AGM batteries need a much smarter way of being charged properly.


Here’s an extract from OPTIMA:


Here are a couple of things to...

• Dellmassive
• charging how to guide
• Replies: 87
• Forum: Electrics, Lighting, ICE, Security

• 
• 

 

[Dellmassive]

Also see here is you have a leisure battery...



[Guide] Battery Maintainer (for Starter battery) -- How I Done It --

Thread '[Guide] Battery Maintainer (for Starter battery) -- How I Done It --'

25 Nov 2020

[Guide] Battery Maintainer (for Starter battery) -- How I Done It --

Right so its that time of year again . . . . . . . . Winter & (Lockdown 2020)




The van might be layed up not being used, which will lead to a flat battery in around 3 weeks.

The cold weather doesn't help the battery's either.






This Thread is about using "what you have" to "back charge" the starter battery...

lets look at some options. . . . . . . .

1# Connect a 240v/EHU charger to the starter battery and leave it connected, that's fine if you have a drive way etc, have a look for the...

• Dellmassive
• battery drain dellmassive how to guide vehicle battery
• Replies: 108
• Forum: Electrics, Lighting, ICE, Security

• 

 

[Salty Spuds]

I had an Optimate charger fitted when I changed to a Lithium LB, that also threw up errors and wasn’t suitable for the purpose. They (Optimate) seem to have some sort of pre-charge test sequence where a small metered charge is applied to the battery and then a pause of around 5 mins. If the battery voltage drops in that pause period, the charger decides that the battery is faulty and throws the teddy out of the cot. Now this is all well and good for a battery that’s sat on a bench and disconnected from any loads. Where the system falls down is when the battery is “in situ” and supplying a load as it’s also being charged. So what happens is the Optimate starts the test sequence, applies a small charge and measures the battery voltage, then waits. Meanwhile your starter battery is still connected to the van, and assuming that you’re working around the van and opening doors/bonnet etc, the van has “woken up” and is doing its stuff, all this takes battery power causing the voltage to drop. 5 minutes later the charger completes its test cycle and sees the battery voltage is now lower than at the start of the test and decides the battery is Fubar. The charger isn’t as smart as it thinks it is.
Victron chargers don’t do this.

 

[StratosFearXX]

Thanks yeah that makes sense.

 

[StratosFearXX]

I usually charge with the Optimate under the bonnet, it may be throwing the error when I unlock the van to open the bonnet I suppose.

 

[StratosFearXX]

Update, if you leave it on and connected for three days straight the charger carries on charging/conditioning the battery and doesn't throw the error.