Head to head
Redarc 40A vs Victron 30A DC-DC Chargers
Both do the same job. The question is which one your boat is actually asking for — and on this site that is a number, not a preference.
| Redarc 40 A | Victron 30 A | |
|---|---|---|
| Charge current | 40 A | 30 A |
| Price band | $520–$720 | $380–$540 |
| Best suited to | A 90 A alternator feeding a 200–400 Ah bank — the commonest boat on this site. | A 60 A alternator, or a 200 Ah bank where 30 A is the cell-side ceiling. |
| Look elsewhere if | You want alternator temperature sensing as standard rather than as an add-on. | You have a 120 A alternator and a large bank — you are leaving charge on the table. |
Redarc 40 A
The unit most Australian installers fit without being asked, and the one whose wiring diagrams every auto-electrician already knows.
Victron 30 A
The smaller Victron, and the sensible answer on a boat with a modest alternator that talks to the rest of a Victron system.
Sized for your boat
40 A
Charge current for a 400 Ah bank on a 90 A alternator
This is a ceiling, not a target. A charger larger than your alternator can sustain is the failure this whole page exists to prevent, so we list what fits at or under it — biggest first.
5 options fit — the first is the one we would fit
The honest answer
Size it first, then choose.
A head-to-head between two ratings is the wrong question if neither matches your boat. Work out what the boat needs, then pick between whatever meets it — which is usually a decision about support and documentation rather than about amps.
Before choosing Redarc 40 A and Victron 30 A
Match the charger to the installed charging system
Check the input source, battery requirements and the alternator’s available continuous output under actual operating conditions. Include other engine electrical demand in the assessment. Maximum charger output is not a promise of output at every temperature or speed, and the design needs to account for control signals and protection behaviour as well as current.
Confirm specifications against the exact model and revision offered by the supplier. A listed price band is a planning reference; request a current written quote with installation and commissioning separated from equipment supply.