Specifications are subject to change. See bluesea.com/P12 for current information.
* Consult battery manufacturer specifications for other batter y types to avoid damage. Do not mix battery types.
** Battery bank sizes are recommended for optimal charging efficiency-see bluesea.com/P12 for details. Larger and smaller size banks could charge well, but consume slightly
more power over the charging cycle.

Regulatory

Designed and constructed for compliance to UL-1236 Marine, CSA 22.2 No. 107.2, and ABYC A-31 standards. Ignition Protection per ISO 8846, and SAE J1171.
Meets FCC Part 15, Class B requirements. To view current regulatory specifications visit www.bluesea.com/P12.
Specifications

7521 7522

Total Output Current 25A 40A
Input AC Current 4.5A @ 100V AC / 2.25A @ 200V AC 7.5A @ 100V AC / 3.75A @ 200V AC
Nominal Output Voltage 12V DC 12V DC
Output Connections 3 positive, 1 negative 3 positive, 1 negative
Universal AC Input Voltage 90V–265V AC 90V–265V AC
Input Frequency Range 45–65 Hz 45–65 Hz
Typical Float Voltage 13.5V DC 13.5V DC
Maximum Available Voltage 16.0V DC 16.0V DC
Output Voltage Accuracy 0.05V DC 0.05V DC
Minimum Operating Temperature −20°C (−4°F) −20°C (−4°F)
Maximum Operating Temperature 70°C (158°F) 70°C (158°F)
Minimum Storage Temperature −30°C (−22°F) −30°C (−22°F)
Maximum Storage Temperature 80°C (176°F) 80°C (176°F)
Warranty 5 Year 5 Year
Battery Types* Flooded, Gel, AGM, TPPL (Thin Plate Pure Lead) Flooded, Gel, AGM, TPPL (Thin Plate Pure Lead)
Recommended for Battery Bank Sizes** 160Ah Minimum, Example: 2 x Group 27
330Ah Maximum, Example: 3 x Group 31
220Ah Minimum, Example: 2 x Group 31
440Ah Maximum, Example: 4 x Group 31
Conductor Length in feet (meters) Charger Rating
25A 40A
6 ft (1.83 meters) 14 AWG (2.5mm²) 8 AWG (10mm²)
10 ft (3.05 meters) 12 AWG (4mm²) 8 AWG (10mm²)
15 ft (4.57 meters) 10 AWG (6mm²) 6 AWG (16mm²)
20 ft (6.09 meters) 8 AWG (10mm²) 6 AWG (16mm²)
25 ft (7.62 meters) 6 AWG (16mm²) 4 AWG (25mm²)
Recommended Battery Fuse 30A 60A
Region Line Neutral Ground (Earth)
North America Black White Green
Europe Brown Blue Green-Yellow
Australia/ New Zealand Brown or Red Blue or Black Green-Yellow

Table A: Minimum Recommended Wire Size*

Appropriate Fuses and Fuse Holders Charger Rating
Fuse Type Fuse Holder 25A 40A
MRBF Terminal Fuses 5191 Terminal Fuse Block 5175 (30A Fuse) 5178 (60A Fuse)
AMI®/MIDI® Fuses 7720 Safety Fuse Block 5250 (30A Fuse) 5253 (60A Fuse)

Table B: Recommended DC Circuit Protection

Table C: Typical AC Regional Wire Colors

Table D: AC Wire - Circuit Protection Selection Chart

7521 (25A) 7522 (40A)
Input Watts 450 750
120V AC Application 4.5A @ 100V AC 7.5A @ 100V AC
Minimum AC Wire Size 18 AWG (0.75mm²) 16 AWG (1.5mm²)
Circuit Breaker 10A 15A
230V AC Application* 2.25A @ 200V AC 3.75A @ 200V AC
Minimum Wire Size 18 AWG (0.75mm²) 18 AWG (0.75mm²)
Circuit Breaker 5A – 10A 5A – 10A
* Typical of Europe
Type Absorb Volts Float Volts
FLA – Flooded Lead Acid 14.5V 13.5V
AGM – Absorbed Glass Mat 14.35V 13.3V
Gel – Gelled Electrolyte 14.1V 13.5V
TPPL – Thin Plate Pure Lead 14.7V 13.6V¹
User Adjustable 12.5V Default 12.5V Default
¹ Taken from Odyssey Tech Notes, Northstar operation Manual

Table E: Default Voltages by Battery Type

Batteries should match in chemistry, although many AGM’s and flooded batteries are
compatible. Based on 25°C (77°F)
5
* Based on 3% voltage drop. If fast charge recovery is important, use larger wire. Double the conductor
length entry to get a 1.5% drop, triple the conductor length to get a 1% voltage drop.
P12
7521 AND 7522 BATTERY CHARGERS