BI 1203, 120 A, 12/24 V

Mastervolt’s BI battery isolators are based on conventional diode technology. The diode voltage drop (ca. 0.6 V) can be compensated for by adapting the output voltage of the connected charger or alternator. Mastervolt battery chargers and Alpha Pro MB charge regulators come as standard with automatic voltage drop compensation.

Compact and lightweight

The Mastervolt BI battery isolators are compact and fully solid state, preventing wear. The weight varies from 580 to 1300 grams.

Robust and durable

Completely corrosion-proof material with aluminium heat sinks. The electronic components are encased in synthetic materials, the BI models have molded diode splitters.

Fast installation

The synthetic end plates feature connection lugs, the solid bolt connections with nuts and locking rings ensure easy installation.

Product code: 83012030 This product is no longer available.
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General specifications
Dimensions, hxwxd 207 x 140 x 80 mm
8.1 x 5.5 x 3.1 inch
Weight 1.2 kg
2.6 lb
Technical specifications
Compensation diode no


User manuals

BI 1203, 120 A, 12/24 V

Users Manual Battery Isolator BI702, BI702S, BI703, BI1202, BI1202S, BI1203, BI1203S