3008 currently does not include any d.c. values.
For CCC, the 50 Hz values will be close enough, and the citation in 5033 provides bum-cover to ignore any differences.
There are d.c tables widely available, but rather than using Vc values that allow us to calculate actual VD; they generally tabulate max run vs current to provide the standard size of cable that will not exceed a stated amount of VD.
So a different table for each VD limit, and for each nominal voltage.
Typically they are available for 12 V & 24 V; and the VD limits generally used are 3 % for voltage-sensitive equipment1 (eg winches) and 10 % for general loads.
Also the distance axis of these tables is typically not "route length" but total circuit length, ie there & back again (via any switching detours)
Just to complicate matters further, many use AWG cable sizes (as commonly used for automotive electrical work)
But FirstFlex have one that uses CSA in mm2; they also provide d.c. resistance data (ohms per km)
www.firstflex.co.nz/information/technical-information/
The tabulated format for VD works OK for single circuits at the nominated voltages; but difficult for composite circuits where different sizes of cable are used for various parts and no use of you happen to be using a different nominal voltage.
So if dealing with those, need to back-calculate the Vc values from the data given - and the results will be close to the single-phase 50 Hz values in "3008".
I've only found one source to date that directly gives Vc values for d.c. circuits, in a UK book on wiring for boats; and the values are all a bit below those for single-phase derived from Table 42 in "3008.1.2" .
While single-phase values for mV/A/m derived from 3008 will be close enough (in fact conservative); what's missing is the limit for max VD.
In the absence of any specific rule for d.c. circuits; clause 3.6 applies; so max = 5 %.
As above, auto-sparkies generally work on 3 %. Noting that when you start with only 12 V, 3 % is SFA.
And that makes the variations in resistance (and therefore Vc) for temperature more significant.
If you regard solar power as "free" energy, maybe losses in the d.c. cabling can be disregarded compared to the cost of reducing losses by using bigger cables. But volt drop is essentially using the harvested energy to heat the environment, when it would be better used to do what we want it to do.
Due to d.c being increasingly used in installations, d.c values are being added to "3008" for next edition.