Alternator voltage control for Volvo D2 series

[Island Time 1,220]

When I did my engine replacement last year I was asked about how I got around the fixed (14.4v) single stage voltage regulator without voiding the engine warranty.  

 

At that stage I had not altered the factory setup in any way. However, I'd been used to a decent setup (80amp Balmar 6 series alt on a Next Step 3 stage reg), and eventually got around to sorting this out over winter.

 

The provided alternator with the D2-40f that I fitted is a 115a, internally regulated alt with external voltage sensing. This is common for the whole D2 series. The voltage sensing is a step forward, as for example if you are using the alt to charge dual banks thru a diode based splitter it will compensate for the voltage drop. The alt also has internal overheat control, backing off the charge rate before the alt melts. Good alts don't melt, even at full output for long periods, but this feature is better than nothing.

 

Volvo say that to modify the system in any way will void the warranty, which IMO is bollocks, and I don't think would legally stand up if challenged.

 

So, if you motor for extended periods on full batts, the std 14.4v is well above the float voltage for most batts, and will at least shorten their life expectancy, or at worst kill them off. If you want Lithium batts or some other tech, likely you cant have it at 14.4v.

 

This puts the owner in a difficult situation. Options are put up with poor battery management, or void the warranty.

 

Until now. NORDKYN Electronics have come up with a controller for externally sensed alts and chargers. Its called a VRC-200 Charge Reference controller. It needs NO modification to the alternator or regulator, and simply connects to the factory voltage sense wire from the alt. Its fully programmable, and if you have a battery computer with a shunt, it will connect to that as well so it knows what current the battery is receiving. 

 

This is a great bit of kit. No, I don't sell it, you can buy it online HERE. 

So, you can adjust

Bulk/Absorption voltage,

Absorption Time

Absorption cut out (Tail) current

Float voltage

Max Charge rate 

And it can have temp sensors for the batt and the alternator.

 

Setup requires a reasonable multimeter and a bit of understanding. I'd be happy to help anyone who needs it.

 

I've been running mine now for a few months with good results. The only issue I've had is that the stupid volvo alarms cant be re-set to the new voltages, and so I've had to drop the max charge voltage to 14.5 rather than the 14.7 my batts can take, to avoid the alarm triggering.

 

[CarpeDiem 430]

I just got the D1-30, pretty sure it's the same 115A alternator. I also had a Next Step and didn't want to butcher the alternator.

 

I went down the DC/DC route and settled on the CTEK250 coupled with the CTEK120. It includes solar, low voltage cut out and even float charges the starting battery from the house battery when the house is full. I currently use the solar input attached to a fixed 14.8v 10amp shore power supply whilst I decide on solar.

 

I dislike that I can't adjust or tweak any of the settings but the factory values are ok.