Victron Energy Cyrix-i 400 Intelligent Battery Combiner

Introduction

The Victron Energy Cyrix-i 400 is a microprocessor-controlled, heavy-duty battery combiner designed to automatically connect and disconnect batteries in parallel. It ensures that batteries are charged when voltage is high and isolated when voltage drops, preventing discharge of the starter battery.

Key Features

• No Voltage Loss: Acts as a replacement for diode isolators, offering virtually no voltage drop.
• Prioritizes Starter Battery: Ensures the starter battery is always charged first, then connects other batteries for parallel charging.
• Bidirectional Voltage Sensing: Monitors voltage on both connected batteries, allowing charging from alternators or battery chargers.
• Intelligent Battery Monitoring: Offers four selectable connect/disconnect profiles to suit various requirements.
• Auto-Ranging Voltage: The Cyrix-i 12/24 automatically adjusts to 12V or 24V systems, and the Cyrix-i 24/48 adjusts to 24V or 48V systems.
• Bicolour LED Status Indicator: Provides clear visual feedback: Red (contactor open), Red/Green (timer active), Green (contactor closed).
• Remote Monitoring: Features a micro switch for external status indication.

Installation

Follow these steps for proper installation:

1. The Cyrix is designed for installations with a common negative ground.
2. Disconnect the negative terminal from both batteries.
3. Mount the Cyrix as close as possible to the smallest battery (typically the starter battery).
4. Connect the positive terminals of both batteries to the brass bolts on the Cyrix (labeled Battery 1 and Battery 2). Install a fuse in series with the positive connections, sized appropriately for the wire gauge but not exceeding 400A.
5. Connect the common negative battery terminal to the "battery -" terminal on the Cyrix, and then reconnect the negative terminals to their respective batteries.
6. An optional "Start Assist" button can be wired to the "start assist" connection. Activating this button will close the relay for 30 seconds, allowing for emergency starting. Alternatively, a parallel connect switch can be used to keep the relay closed for the duration the switch is active.
7. An auxiliary micro switch is available for remote status monitoring.

Wiring Diagram Description

The system diagram illustrates the Cyrix-i 400 connecting a starter battery (Battery 1) to a domestic battery bank (Battery 2). An alternator is connected to the starter battery. A charger is shown connected to the domestic battery bank. The Cyrix-i unit has terminals for Battery 1, Battery 2, and a "Start Assist" input. A maximum fuse rating of 400A is indicated. The diagram also shows a "Profile Select Switch" which is accessible by removing a cover on the unit.

Specifications

Connect/Disconnect Profiles

The Cyrix-i offers four configurable profiles to manage battery connection and disconnection based on voltage thresholds and time delays. Voltage values indicated are for 12V systems; multiply by 2 for 24V systems and by 4 for 48V systems.

Profile 0 (Default)

Profile 1

Profile 2

Profile 3

Notes and Warnings

• After 3 consecutive connection cycles, a minimum delay of 1 minute is enforced to prevent rapid switching ('rattling').
• The Cyrix will not connect if the voltage on either battery terminal is below 2V* (to prevent unexpected switching during installation).
• The Cyrix will always connect if the "Start Assist" function is activated, provided the voltage on at least one battery is sufficient to operate the unit (approximately 10V*).
• *Multiply voltage values by 2 for 24V systems and by 4 for 48V systems.