Thread: D3 voltage levels.

Is the update to lower the output amps or just change the charge profile ?

Originally Posted by loanrangie

Is the update to lower the output amps or just change the charge profile ?

Hi and No, I have been testing charging of lithium batteries with a non SMART alternator operation.

While D3s have a SMART alternator, so far I have not come across one that charged at less than 13.5v.

This makes them ideal for charging lithium batteries.

BUT, I am aware of D3s overseas, have charging voltages as high as 15.4v and this is an absolute No-No for lithium batteries.

The Traxide DT90 and new UST-175 isolators have an Over-voltage safety shut down of 15.1v, but this again is still too high.

As I posted above, I have a few customers with Defenders, charging lithium auxiliary batteries with no problems.

But D1s, D2s ( I am not sure about the D2a ) Series, Defenders and Pumas do not operate above 14.7v

I am considering adding a customer selectable Over-Voltage shut down of 14.7v, to be set when ever someone is charging a lithium auxiliary in a D3.

I would still like to know the maximum voltage reached with Australian D3s and more importantly, how long they operate at the highest voltages.

Tim - I looked through all the trends that my BM2 has recorded, and from what I can see my ‘08 D3 always charges between 13.7-14.1V. Most of the time is probably around 13.8-13.9V.

I am more surprised I don’t see any higher voltages when charging (when the engine is running).

Edit: should note - I do have an 80W solar panel and this wired via the 15A fuse at the rear compartment but I am sure once the engine is running this contributes very little.

On a cold start when the temps are < 5C I often see charging setpoints on the GAP of > 15V, but in practice I've never seen much above 14V.

Originally Posted by DiscoDB

I can see my ‘08 D3 always charges between 13.7-14.1V. Most of the time is probably around 13.8-13.9V.

As did my D4 2.7,which i believe had a similar system and no smart alternator.

The 3.0L D4 was different.

I have seen 14.5V on my D3 but generally high 13 to low 14's.

Originally Posted by scarry

As did my D4 2.7,which i believe had a similar system and no smart alternator.

The 3.0L D4 was different.

Hi Scarry and the D3 and 2.7 D4 do have a version of a SMART alternator.

The primary difference is that the D3/2.7 D4 voltages never go down below about 13.5.

But unlike Variable voltage alternators, as found in Toyotas and the likes, where they do not monitor the cranking battery, D3s and 2.7 D4s do actually both monitor the cranking battery and adjust the charge algorithms to best suit the charge needed based on the condition of the cranking battery.

Originally Posted by loanrangie

I have seen 14.5V on my D3 but generally high 13 to low 14's.

Tim due to the issues I've had over the last couple of weeks the BM2 currently does not have much to offer. I too have had 14.5V on the live readings on the Nanocom (used while on longer trips) and regularly the same sort of consistency like loanrangie & DiscoDB. HTH.