The ARCO Zeus A8000-48V is a 48V high-output alternator that makes up to about 9.6 kW. That is enough to recharge a large 48V house bank from the engine. It uses a native 48V rotor, rather than a 12V rotor pushed to 48V, so the regulator is not fighting the alternator to hold voltage down.
Ratings are at 53.5V and at the alternator shaft (engine RPM × pulley ratio):
| Peak, cold (9,000 alt RPM) | 180 A (about 9.6 kW) |
|---|---|
| Sustained hot, cruising (6,000 alt RPM) | 138 A (about 7.4 kW) |
| At 4,000 alt RPM | about 111 A (almost 6 kW) |
| At 2,500 alt RPM | about 55 A (over 3 kW), continuous |
| Starts charging at | about 1,920 alt RPM |
| Max continuous operating temperature | 212°F (100°C) |
From ARCO’s examples: a marine diesel at 1,200 RPM with a 3.13:1 pulley ratio gets just over 5 kW, and a Sprinter at a 750 RPM idle (3.21:1) still gets over 3 kW.
External regulation only: it needs an external regulator such as the ARCO Zeus regulator, which also handles lithium charge profiles. This listing’s default housing is the 3.15″ J180 saddle with an isolated ground (ARCO part 4601); other housings are in the options above. Not sure 48V is right for you? Read 24V vs 48V: which is right?
Choose the housing that matches the alternator you are replacing:
| 1–2″ single foot | Most domestic single-foot alternators (e.g. Motorola, Prestolite). |
|---|---|
| 3.15″ J180 saddle | Most small-case saddle alternators (e.g. Hitachi, Lucas, Mitsubishi) and most Yanmars. |
| 3.15″ saddle, rear-exit B+ (common rail) | Required on Yanmar common-rail engines after 2013. |
| 4″ J180 saddle | Most Volvo Penta 4″ J180 mounts, and many larger industrial-based engines. |
| Vortec / GM pad | Mando-type alternators with Vortec/GM feet (many MerCruiser and Volvo Penta gas engines). |
| N62 with clutch pulley | The factory second alternator on many Sprinter-based RVs. |
| Ford Transit | Ford Transit dual-alternator setup, 3.5L and 3.7L gas, 2015–2022. |
Not sure? Send us a photo of your current alternator’s mounting feet and we will match it.
Like every Zeus alternator it is built in the USA by ARCO Marine of Pensacola, Florida, and is SAE J1171 certified (ignition-protected for marine engine rooms). Inside: a 16-pole rotor, a large-frame 138 mm stator, dual cooling fans and avalanche-rated diodes, with the rectifier outside the housing to keep heat away from it.
Planning a 48V system? Call us on (410) 216-2907 or start with the Power Guide.