ARCO Zeus A275L J-180 4-Inch Alternator, Terminal Block

Description

The ARCO Zeus A275L J-180 4-Inch Alternator with Terminal Block is a high-output 12V charging solution for marine, RV, military, and commercial systems that require rapid recovery of large battery banks and substantial current at both cruising and idle speeds. This version uses a 4-inch J-180 saddle-style mounting arrangement intended to replace many Volvo Penta alternators.

ARCO designed the A275L to sustain output by aggressively controlling heat. Heat-shedding E-Coat or Cerakote, an externally positioned rectifier, dual cooling fans, and OEM-grade components help the alternator run cooler than conventional high-output designs. Lower housing and rectifier temperature translates to more amperage being available for longer periods and can help reduce dependence on a generator.

This large-frame unit uses a 138mm stator, 16-pole P-type field, and external-only regulation. It is supplied with a terminal block and P-type harness and requires an external regulator such as the ARCO Zeus Bluetooth Alternator Regulator. That architecture also supports advanced lithium charging strategies. Default output voltage is 14.1V.

ARCO publishes a cold maximum of 311A at 9,000 alternator RPM, sustained hot cruising output of 227A at 6,000 RPM, and sustained hot idle output of 198A at 3,000 RPM. Cut-in speed is 1,061 RPM, maximum alternator speed is 19,000 RPM, and maximum continuous operating temperature is 110°C.

The alternator uses an M8 side-mount battery post, a 49K6 six-groove 49mm pulley, 17mm shaft threaded M17 x 1.5, included pulley nut and washer, and six positive plus six negative 50A avalanche-rated diodes.

This 4-inch J-180 configuration is intended to replace many Volvo Penta alternators using the same saddle-style mounting arrangement. The A275L is SAE J1171 certified and made in the USA. Look through the rest of our marine alternators.