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from 25 reviewsIt’s been great to further explore projects in the RV sector thanks to products like the ARCO Zeus range. There seems to be a huge demand for off grid overlanding adventure, which is made far easier by products from these great suppliers!
You are going to like how quick your battery bank charges after you crank up the engine
An external alternator regulator that's Lithium ion battery aware is a good thing.
The Zeus is a very good piece of equipment. More important, when a problem arise, the customer service is excellent!!!!!!!
This is very exciting! Nothing else comes close to this I hear!
RV owners can achieve charging efficiency through the ARCO Zeus 250A 48V alternator with a Bluetooth-enabled smart regulator. With this feature, they can charge the vehicle while it operates, minimizing generator reliance and downtime.
The ARCO Zeus alternator regulator is connected to the Lynx Smart BMS NG, allowing it to receive real-time battery data, such as voltage and current, and adjust charging accordingly. This also enables real-time monitoring of alternator output and battery charge status on the Cerbo GX touch display, or from anywhere in the World via the VRM Portal.
One of the most exciting integrations we’ve seen has been with the Zeus Alternator Regulator. The combination of Expion360’s intelligent battery management system (BMS) and Zeus’ advanced regulation technology has proven to be an outstanding pairing, offering precise control and optimized charging performance. With CANBus communication, our batteries seamlessly relay critical data—such as state of charge (SOC), voltage, temperature, and charge/discharge status—to the Zeus Regulator, ensuring a more efficient and safe charging process.
We’ve seen overwhelmingly positive feedback from users who have adopted this system, particularly in high-demand applications like marine, RV, and off-grid energy setups. The combination of Expion360’s CANBus and SmartTalk-enabled batteries with the Zeus Alternator Regulator has set a new standard for intelligent energy management, delivering unmatched performance and reliability.
They’ve developed an incredible app that makes navigation and programming exceptionally user-friendly. With a slight adjustment, Renogy's REGO 12V 400Ah Battery is now a pre-set profile on the Zeus Bluetooth Regulator app, enabling seamless monitoring and charging. We’re excited to collaborate in driving the growing adoption of the Zeus regulator while expanding our own 12V battery charging capabilities through alternator regulators.
When you wake up in the morning and the batteries are shut down it doesn't take the Zeus regulator long to top up batteries for the coffee maker.
We are underway on the Salish Sea and Zeus is performing perfectly with the EPOCHs and Victron!
Since Spring I have been part of a technical advisory board to help ARCO MARINE develop a new alternator regulator. The concept was to keep it simple to use and program while offering all the features of the most demanding boater or technician. We worked directly with ARCOs engineers to create state of the art charging, for any battery chemistry, while able to protect small engines with large alternator output. There are many new features included, that I have personally been testing on my own cruising sailboat this season, and the ARCO Zeus regulator has been spot on for my LiFePO4 batteries. I know of nothing in the industry that compares to the functionality of the ARCO ZEUS Regulator.
I have recently purchased an ARCO alternator from you and am very pleased with the appearing quality and function. I am a full-time auto mechanic and your quality is far above anything I see from auto parts stores. So far, I am very impressed with your products.
The performance of this unit really has lived up to the impressive test results ARCO has published. Really amazing power at idle RPMs, and it runs really cool when doing it. The smaller size of the frame (compared to other large frame units) should make install easier (it did on this install for sure).
Certainly the core design (windings/rectifier) appear to be state of the art, and I have high hopes for the cerakote.
This is the first time trying out 2 of your Zeus regulators on a customers boat. The quality looks great and I'll be using them in the future if all goes well.
ARCO Zeus A275L High Output Alternator
- Price
- $1,136
Description
High Output / High Amperage Alternator: The Highest Power Output in Its Class
- Replace your noisy generator!
- Engineered for high energy production.
- Suitable for marine, RV, military, and commercial applications.
- Rapidly charges large battery banks.
- Coolest operating temperatures for increased performance:
- Heat shedding coatings
- Rectifier located on housing exterior
- Dual cooling fans
- OEM components
- Optimized for performance at idle speeds.
- Reduces the need for a generator by creating additional power with your engine.
- Unleash peak performance with E-Coat/Cerakote, keeping the A275L cooler for sustained amperage output.
- For maximum performance or lithium battery charging, use the ARCO Zeus Bluetooth Alternator Regulator.
- SAE J1171 Certified.
- Models available with internal/external voltage regulator.
- Proudly made in the U.S.A.
Technical Specifications
Voltage | 12V |
Field Type | P |
Rotor Poles | 16 |
Stator Size | 138mm |
Frame Size | Large |
Weight | 14.9 lbs / 6.7 kg |
Regulation | Internal/External (IE) or External Only (EX) |
Output Voltage | 14.1V (default) |
Finish | (Black) Cerakote or E-coating |
Cut-In RPM | 1,061 Alternator RPM |
Maximum Alt RPM | 19,000 |
Battery Post | M8 Thread Post, Side Mount |
Standard Pulley | 49K6 (6-groove, 49mm) |
Pulley Mount | 17mm diameter shaft, 25mm long, threaded M17 x 1.5 |
Pulley Hardware | M17 x 1.5 x 24mm nut, w/ 18mm ID x 29mm OD washer (Included) |
Diodes | 6 positive, 6 negative, 50A Rated, Avalanche |
Max Output (Cold, 9,000 RPM) | 311 Amps |
Sustained Cruising Output (Hot, 6,000 RPM) | 227 Amps |
Sustained Idle Output (Hot, 3,000 RPM) | 198 Amps |
Max Continuous Operating Temperature | 110°C / 230°F |
Mounting Options and Applications
Mounting | ARCO Part Number | Application |
1-2” Single Foot | 4027 4028 4029 4030 | Replaces most domestic styles using a single 1" or 2" mounting foot (e.g., Motorola, Prestolite). Requires Standard single "V" belt upgrading to a double "V" belt or Serpentine System |
3.15” Saddle | 4019 | Replaces most small case styles using a 3.15" saddle style mount (e.g., Hitachi, Lucas, Mitsubishi). Most Yanmars. Requires Standard single "V" belt upgrading to a Serpentine System |
3.15”R Saddle (Rear exit B+ post) | 4020 4021 | Must be used on Yanmar Common Rail introduced after 2013 (JH-CR, 3JH40, 4JH45, 4JH57, 4JH80, 4JH110) |
4” J180 Saddle | 4022 4023 4024 4025 | Replaces most Volvo Penta alternators using a 4” J180 saddle style mount |
Vortec | 4033 4034 | Replaces Mando type alternators using Vortec/GM pad mounting feet (Found on many Mercruiser and Volvo Penta 3.0GLM, 3.0GLP, 4.3GXi, 5.7GiL, 5.7GXiL Marine Engines.) (GM Blocks) |
Transit | 4031 4032 | Replaces Ford Transit alternators for 3.5L & 3.7L Gas engines 2015-2022 |
N62 (Clutch Pulley) | 4026 | Mercedes Sprinter 1999-2006 alternators, Mercedes Sprinter Factory dual alternator 2007-Up Replacement, Replaces Roadtrek Mercedes Dual alternator |
Regulation
External Only (EX): These units will come with a terminal block and a P-Type harness. They will only work with an external regulator, such as an ARCO Zeus Bluetooth alternator regulator.
Internal/External (IE): Internally regulated with adaptor for optional external regulation.
Transparency - How We Test For Output
To measure sustained output, the alternator is run at 3,000 RPMs for 60 minutes with a plexiglass shield covering the units. Testing shows that after 60 minutes in these conditions, alternators reach their maximum operating temperature, or the conditions under which the unit will produce the least output.
It is under these harsh conditions where we measure the “hot” output of the units at various RPMs. The complete power curve is shown above.
Note: The “hot” conditions are much less favorable than the conditions typically used in the industry. The temperature of the stator during our “hot” test was 305 °F. Incumbents measure the power curve at an ambient temperature of 140 °F. “Cold” testing was done at 71° F.
Cross-Reference
Unit Part #s | Superceeded Part Number | Voltage | Size | Housing | Regulation | Pulley | APS | Mechman | Balmar |
---|---|---|---|---|---|---|---|---|---|
4019 | A275L-12-DF315-EX-IG-49K6 | 12V | Large (138mm) | 3.15 | External Only | 49K6 | 360HSB1H652S9E4 | - | N/A |
4020 | A275L-12-DF315R-EX-49K6 | 12V | Large (138mm) | 3.15 | Internal or External | 49K6 | - | - | XT-CR-250-K6 |
4022 | A275L-12-DF4-EX-49K6 | 12V | Large (138mm) | 4.00 J180 | External Only | 49K6 | 42i-270-14JEXT/STA | - | N/A |
4024 | A275L-12-DF4-IE-49K6 | 12V | Large (138mm) | 4.00 J180 | Internal or External | 49K6 | 360HVOPRIG1H852S9E2 | - | XT-DF4-250-K6 |
4026 | A275L-12-N62-EX-50K6CP | 12V | Large (138mm) | N62 | External Only | 50K6CP | 360HN621H652S9CE4 | - | XT-MS-250-K6 |
4027 | A275L-I2-SF12-EX-49K6 | 12V | Large (138mm) | 1" Single Foot w/ 2" Spacer | External Only | 49K6 | - | - | N/A |
4029 | A275L-I2-SF12-IE-49K6 | 12V | Large (138mm) | 1" Single Foot w/ 2" Spacer | Internal or External | 49K6 | - | - | XT-SF-250-K6 |
4032 | A275L-12-TR-EX-62K4 | 12V | Large (138mm) | Ford Transit | External Only | 62K4 | - | 11630320 | XT-EB-250-K4 |
4033 | A275L-12-VT-EX-49K6 | 12V | Large (138mm) | Vortec | External Only | 49K6 | - | - | N/A |
4034 | A275L-12-VT-IE-49K6 | 12V | Large (138mm) | Vortec | Internal or External | 49K6 | 360H15RVC1H652S9C | M8206250 | XT-VT-250-K6 |
SKU Details
Voltage | Maximum Output (Amps) | Sustained Idle Output (Amps) | Housing | Regulation | Pulley | Unit Part # |
12V | 311 | 198 | Vortec (GM) | External Only | 49mm K6 | 4033 |
12V | 311 | 198 | Vortec (GM) | Internal or External | 49mm K6 | 4034 |
12V | 311 | 198 | Ford Transit | External Only | 62mm K6 | 4032 |
12V | 311 | 198 | Ford Transit | External Only | 49mm K6 | 4031 |
12V | 311 | 198 | 1"-2" Single Foot | External Only | 49mm K6 | 4027 |
12V | 311 | 198 | 1"-2" Single Foot | Internal or External | 49mm K6 | 4029 |
12V | 311 | 198 | 1"-2" Single Foot – Isolated Ground | External Only | 49mm K6 | 4030 |
12V | 311 | 198 | N62 | External Only | 50mm K6 OAP | 4026 |
12V | 311 | 198 | 3.15" J180 | External Only | 49mm K6 | 4020 |
12V | 311 | 198 | 3.15" J180 – Common Rail – Isolated Ground | External Only | 49mm K6 | 4021 |
12V | 311 | 198 | 3.15" J180 – Isolated Ground | External Only | 49mm K6 | 4019 |
12V | 311 | 198 | 4" J180 | External Only | 49mm K6 | 4022 |
12V | 311 | 198 | 4" J180 | Internal or External | 49mm K6 | 4024 |
12V | 311 | 198 | 4" J180 – Isolated Ground | External Only | 49mm K6 | 4023 |
12V | 311 | 198 | 4" J180 – Isolated Ground | Internal or External | 49mm K6 | 4025 |
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