The Victron Cyrix-ct is a microprocessor-controlled battery combiner for 12V and 24V systems carrying up to 230A continuous current. It joins battery banks in parallel while a charging source is active and separates them again once charging stops, so a starter battery cannot be drained by auxiliary loads. It suits marine, vehicle and off-grid setups where two battery banks need managing without a manual switch.

Key features

• Automatic combining, the relay closes and opens based on voltage thresholds, with no manual switching needed.
• Current rating, 230A continuous at 12V or 24V DC.
• Starter protection, disconnects the auxiliary bank once system voltage drops below the set threshold.
• Chemistry compatible, works with lead-acid, AGM, gel and lithium batteries as it responds to voltage rather than chemistry.
• Compact build, weighs 0.3kg for installation in tight spaces.
• Charger compatible, works alongside alternators, solar chargers and shore power chargers without extra configuration.

How it works

The Cyrix-ct monitors the voltage of both battery banks. When either reaches a pre-set charge voltage, the internal relay closes and the banks are connected in parallel so both receive charge current. When voltage falls back below the threshold, the relay opens and the banks separate again, stopping a discharged auxiliary bank from pulling down the starter battery.

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