Voltech DCS-1240 DC to DC Charger

Specifications

Charge Control

Safety Precautions

For safe operation and ideal performance, the DC TO DC charger Intelligent Battery Charger must be installed and operated correctly. Please carefully read, understand, and follow all instructions and guidelines in this User Guide.

Voltech recommends that the DC TO DC charger be installed by a certified technician.

Failure to follow these instructions may result in damage to the unit, property, death, or serious injury.

Disclaimer: While Voltech has taken every precaution to ensure the accuracy of the contents of this user guide, Voltech assumes no responsibility for any errors or omissions.

FURTHERMORE, ALL SPECIFICATIONS AND FUNCTIONALITY MAY CHANGE AT ANY TIME WITHOUT NOTICE.

1. WARNING: People with physical disabilities, visual, sensory, or mental impairments (including children) should not use this device. Children should be supervised to ensure they do not play with battery chargers.
2. DANGER: Do not disassemble or modify the charger, doing so may result in a risk of electrical shock, fire, death, or serious injury.
3. DANGER EXPLOSION HAZARD: Do not use the charger in an environment where flammable fumes or gases are present (such as gas bottles, petrol engines or lead acid battery compartments).
4. DANGER: This charger is only suitable for battery types listed in the manual. Do not use it for other purposes.
5. WARNING: Please select the correct battery charging profile applicable to the auxiliary battery. If the incorrect battery charging profile is selected, it may cause damage to your auxiliary battery or result in fire. If you are unsure of the correct battery charging profile to use, please consult your battery's manufacturer.
6. WARNING: Please use the fuses and wires recommended in this user guide, otherwise, it may result in damage to the charger, risk of electrical shock, fire, death, or serious injury.
7. WARNING: Ensure that the selected battery charging profile's charge voltage does not exceed the battery's recommended maximum charging voltage. If you are unsure of the maximum charging voltage of your battery, please consult your battery's manufacturer.
8. WARNING: Ensure that the continuous output current of the charger does not exceed the battery's recommended maximum charging current. If you are unsure of the maximum charging current of your battery, please consult your battery's manufacturer.
9. Warning: When using the charger to charge a lithium battery, ensure that it contains an inbuilt battery management system (BMS) that features under and over voltage protection with cell balancing. Failure to do so may result in fire, death, or serious injury.
10. DANGER: Never smoke or allow a spark or flame in vicinity of battery or engine. This may cause the battery to explode.
11. LIMITATIONS OF USE: Do not use in connection with life support systems or other medical equipment or devices.

Product Function

Introduction

The DC TO DC charger is suitable for charging all common types of automotive or recreational lead acid and LiFePO4 Lithium 12-volt batteries. The DC TO DC charger can operate on 12- or 24-volt alternators and unregulated 12-volt nominal solar input. The DC TO DC charger features a Maximum Power Point Tracking (MPPT) solar regulator. This allows for the maximum power to be harvested from the connected solar panels, which increases charging efficiency. The DC TO DC charger has been designed with high efficiency in mind, this allows the charger to be compact and suitable for limited space installations. Furthermore, the DC TO DC charger is also designed to isolate the auxiliary battery from the cranking battery, this is to avoid over-discharging the cranking battery.

Key Features:

• Suitable for charging all common types of automotive or recreational 12-Volt lead acid batteries, such as Standard Lead Acid, Gel, AGM, and Calcium, or LiFEPO4 (Lithium Iron/Ferro Phosphate) Chemistry 12-Volt Lithium batteries.
• For 12V Lead Acid based and Lithium LiFePO4 Batteries recommended battery capacity (25A DCDC Model-80-250 Ah) (40A DCDC Model-120-400Ah). For other Lithium-Ion batteries refer to section "Charging Voltage Limits" to confirm if charging Voltage is applicable.
• Suitable for unregulated solar panels 9-32 Volts, up to 300 Watts for 25A mp model and 500 for 40Amp model
• 25A/40A MPPT Solar Regulator
• Dual input from both solar and alternator
• Charging efficiency of up to 95%
• Excellent performance in harsh environments
• IP68 rated, for resistance to dust, water, and shock damage.
• Smart alternator compatible
• In-built Low-Voltage, Over-Voltage, Over-Temperature and Reverse Polarity Protection

2.1 Display Panel:

Image shows the charger's display panel, featuring indicators for SOLAR PRIORITY, ALTERNATOR, SOLAR, CHARGING, FULLY CHARGE, a MODE button, and selectable battery types (STD, AGM/GEL, CAL, LiFePO4). It also shows the current rating (25A/40A) and voltage options (12V, 24V).

2.2 Battery Charging Profile

To change the battery charging profile, press and hold the "Mode" button for at least 3 seconds then release. The battery type indicator will advance one LED to the right. Please note that the next battery type indicator will not illuminate until the "Mode" button is released. Please note it may take up to 2 minutes after any changes for the charger to start charging.

2.3 Solar Priority

The DC TO DC charger is set up with alternator priority as default, as the power from solar can be very unstable, and the charging efficiency can be impacted. However, if you prefer solar charging regardless of its charging efficiency, or your auxiliary battery has a very small load connected and you want to use solar charging as much as possible, you can enable the "Solar Priority" function. The DC TO DC charger will now always select input power from the Solar in connector if the solar input power is above the minimum required power. Please note it may take up to 2 minutes after any changes for the charger to start charging.

To turn "Solar Priority" ON, please press and hold the "Solar Priority" button for at least 3 seconds then release; the "Solar Priority" indicator will now illuminate.

To turn "Solar Priority" OFF, press and hold the "Solar Priority" button for at least 3 seconds then release; the "Solar Priority" indicator will turn off.

LED Indicators

2.4 LED Charge Indicator

The DC TO DC charger will start to charge from solar input if the panel supply voltage is above 9 Volts.

DC TO DC charger Input Voltage

2.6 Fault LED Indicators

Installation

3.1 Install Location

The DC TO DC charger has been designed for installation in a variety of locations on a vehicle, such as the chassis rail, engine bay and in the vehicle cabin. If the charger is mounted externally, please ensure that the charger does not become covered by a build-up of mud. If the charger is to be installed in the engine bay, try to locate the charger away from components that generate high heat (such as Turbochargers and exhaust manifolds) as this will greatly impact the performance of the charger and may cause the charger to overheat and shutdown.

If the charger is to be installed in the vehicle cabin, please ensure there is adequate ventilation around the charger, and that it is not installed in an enclosed space where airflow is restricted.

The temperature of the charger case can typically be 20-30 degrees Celsius above ambient temperature; it is normal for the charger to feel hot and for you to not be able to keep a finger on the surface for more than a couple of seconds as the case can exceed 60 degrees Celsius.

The DC TO DC charger should be installed as close as possible to the battery being charged (auxiliary battery), this allows for more efficient charging of your auxiliary battery. The DC TO DC charger can be mounted with 4 screws (Not included); there are cut outs on the heatsink of the charger where the screws can be affixed.

3.2 Selection of Cable Size

The DC TO DC 25Amp charger cables may not be long enough for your application. If the Anderson connectors need extending, please refer to the table below with the recommended wire sizes. You can select wires that are equal to or larger than the recommended sizes.

Mounting Diagrams

Diagrams show mounting dimensions for the 25A model (163mm height, 70mm width, 118mm depth) and the 40A model (188mm height, 70mm width, 118mm depth), indicating screw cut-outs on the heatsink for mounting.

3.3 Wiring

Before any connections are made during installation, please disconnect the main cranking battery to prevent any short circuits. Please note down any radio anti-theft codes before the battery is disconnected.

Diagram shows wiring connections: Solar (Green), Output (Red), Input (Yellow), Ignition (Blue).

1. Output Anderson connector (Red and Black wires) goes to the battery being charged (the auxiliary battery).
2. Alternator Input Anderson connector (Yellow and Black wires) goes to the main cranking battery.
3. Solar Input Anderson connector (Green and Black wires) connects to an unregulated solar panel.
4. The ignition wire (Blue) is optional, it depends on the vehicle alternator type. For standard alternators, leave this wire disconnected and please ensure that the wire is well insulated to ensure it does not short out. For vehicles with a smart alternator, please connect this wire to a switched ignition source (i.e., a point that supplies 12V only when the key is in the 'ON' position and disconnects when the key is in the 'OFF' position). Usually, this can be found in the vehicle's fuse box and a fuse tap can be used.

3.4 Typical Setup

Diagram illustrates a typical setup showing a solar panel, 12V or 24V starter battery, the Voltech DC to DC battery charger, and an auxiliary battery, all connected within a vehicle.

3.5 Fuse Specifications

All recommended fuses should be connected in series in circuit, and as close as possible to power sources. Bolt down fuses are preferred as they ensure a low resistance connection. Blade type fuses are not recommended as they can result in a high resistance connection which can cause excess heat generation and may damage the fuse holder and/or the wiring. Self-resetting circuit breakers are not recommended as they may prematurely trip due to the heat generated by the large current flowing through the wires.

Please refer to the table below for the recommended fuses. (PLEASE NOTE FUSES ARE NOT SUPPLIED)