Mastervolt ChargeMaster 12/25-3, 24/12-3

1 General Information

1.1 How to Use This Manual

This manual contains important operating and safety instructions for effective and safe maintenance and operation, and for the possible correction of minor malfunctions on the ChargeMaster. Therefore, it is mandatory that anyone operating the ChargeMaster, or with it, is fully aware of the contents of this manual and carefully follows the instructions and important safety information contained herein. Copyright © 2011 Mastervolt. All rights reserved. Any reproduction, assignment, distribution, or saving, in whole or in part, of the contents of this document, in any form, is prohibited without prior written authorization from Mastervolt.

1.2 Validity of This Manual

All specifications, provisions, and instructions contained in this manual apply exclusively to the standard versions of the ChargeMaster distributed by Mastervolt. This manual is valid for the following models:

Throughout the manual, these models will be referred to simply as "ChargeMaster". For information regarding other models, consult the corresponding manuals available on our website: www.mastervolt.com

1.3 Warnings and Symbols

In this manual, instructions and safety warnings are marked with the following icons:

⚠️ PERIL: This is a WARNING referring to possible personal injury or material damage to the battery charger if the user does not (carefully) follow the indicated procedures.

❗ ATTENTION!: Information, directives, and special prohibitions for preventing damage.

A procedure, circumstance, etc., that warrants particular attention.

1.4 Identification Label

The identification label is located on the right side of the ChargeMaster (see Figure 1). This identification label provides important technical information necessary for service, maintenance, and secondary parts ordering.

Figure 1: Identification Label (Diagram showing the label with Part No., Type, Input, Output, Serial No., Design by Mastervolt, Made in PRC)

❗ ATTENTION!: It is strictly forbidden to remove the identification label.

1.5 Responsibility

Mastervolt assumes no responsibility for:

• Damage resulting from the use of the ChargeMaster;
• Any errors in this manual and the consequences thereof.

2 Important Safety Norms

READ CAREFULLY AND KEEP THESE INSTRUCTIONS

❗ ATTENTION: This chapter illustrates the main safety norms and instructions for using the ChargeMaster in residential, recreational vehicle (RV), and marine applications.

2.1 General Norms

1. Before using the ChargeMaster, carefully read all instructions and warnings related to the system and batteries, as well as all relevant sections of this manual.
2. To reduce the risk of electric shock, do not expose the ChargeMaster to rain, snow, splashes, humidity, excessive pollution, or environments with a high risk of condensation. To reduce the risk of fire, do not cover or obstruct ventilation openings. To avoid the risk of overheating, do not install the ChargeMaster in unventilated areas.
3. Using accessories or spare parts not recommended or sold by Mastervolt risks causing fire, electric shock, or personal injury.
4. The ChargeMaster is designed to be constantly connected to AC (Alternating Current) or DC (Direct Current) electrical systems. Installation of the ChargeMaster and any work on it must be performed by qualified, authorized, and competent electricians or technicians, in accordance with applicable regulations and standards.
5. The electrical system must be correctly installed and in good condition. Furthermore, the cable length must be sufficient to handle the ChargeMaster's AC current. Regularly check the condition of the cables, at least once a year. If the cables are too short or have been damaged, do not use the ChargeMaster.
6. If the ChargeMaster has been subjected to a sharp impact, dropped, or damaged in any way, do not put it into service; instead, return it to the technical service department.
7. Except for the connection compartment (see Chapter 4), no part of the ChargeMaster is permitted to be opened or disassembled. There are no user-serviceable parts inside the unit. Therefore, any maintenance or repair must be carried out by qualified, authorized, and specialized technical personnel. Incorrect component assembly can cause fire or electric shock. The connection compartment must only be opened by qualified electricians.
8. To reduce the risk of electric shock, disconnect the ChargeMaster from both the AC and DC electrical systems before performing any maintenance or cleaning. Turning off the control knobs does not eliminate this risk.
9. The ChargeMaster must be equipped with a ground wire connecting it to the AC system's ground terminal. Grounding and all wiring must comply with all national laws and regulations.
10. Short circuits or reverse polarity can cause serious damage to the ChargeMaster, wiring, and accessories. The use of fuses does not prevent damage caused by reverse polarity. Consequently, the warranty does not cover such cases.
11. In case of fire, use the most suitable extinguisher for the type of electrical material.
12. For marine applications in the United States, external connections to the ChargeMaster must comply with the U.S. Coast Guard Electrical Material Regulations (33 CFR 183, Subpart I).

2.2 Explosive Gases

❗ ATTENTION: RISK OF EXPLOSIVE GASES. WORKING NEAR LEAD-ACID BATTERIES IS DANGEROUS. IN FACT, DURING NORMAL OPERATION, BATTERIES EMIT EXPLOSIVE GASES. FOR THIS REASON, BEFORE USING THE CHARGEMASTER, IT IS ESSENTIAL TO READ THIS MANUAL CAREFULLY AND STRICTLY FOLLOW THE INSTRUCTIONS CONTAINED THEREIN.

2. To reduce the risk of battery explosion, please read these instructions carefully, as well as the information provided by battery manufacturers and all equipment intended for use near them. Consult the warnings related to these products.
3. PERIL: To reduce the risk of explosions, never use the ChargeMaster where there is a risk of gas or dust explosions or where anti-flammable protections are required.

2.3 Warnings Regarding Battery Use

1. When working near lead-acid batteries, it is advisable to have someone else nearby who can hear any requests for help and provide assistance.
2. Ensure that there is always a supply of fresh water and soap in the area in case battery acid comes into contact with skin, eyes, or clothing.
3. Wear complete eye and clothing protection. During contact with batteries, avoid touching your eyes.
4. If battery acid comes into contact with skin or clothing, wash immediately with soap and water. In case of eye contact, flush immediately with cold running water for at least 10 minutes and seek immediate medical attention.
5. It is FORBIDDEN to smoke or create sparks or flames near batteries and the engine.
6. Do not short-circuit the batteries, as this could cause explosions and fire hazards! Exercise extreme caution to avoid dropping metal tools onto the battery. Indeed, there is a risk of sparks, short circuits of the batteries, or other electrical parts that could cause explosions.
7. When working with lead-acid batteries, remove any personal metal objects, such as rings, bracelets, necklaces, and watches. A lead-acid battery can produce a short-circuit current capable of melting a ring or similar metal objects, causing severe burns.
8. Use the ChargeMaster in fixed installations, exclusively for charging LEAD-ACID batteries and for power devices dependent on these batteries. Do not use the ChargeMaster to charge dry batteries, commonly used in household appliances, as these batteries could burn and cause injury to persons and damage to property.
9. NEVER recharge a frozen battery.
10. Discharging or charging batteries with excessive voltage can cause serious damage to them. Do not exceed the recommended discharge limit for the batteries in question.
11. Before removing the battery, the ground terminal must be removed first. Ensure all accessories are turned off to avoid electrical discharge.
12. Ensure that the area around the battery is well-ventilated during charging. Consult the battery manufacturer's instructions for this.
13. Batteries are heavy! Consequently, if involved in an accident, they can become projectiles! Ensure they are mounted correctly and securely. Always use appropriate devices for their transport.

2.4 Notice Regarding Life-Support Applications

ChargeMaster is not supplied for use with medical equipment applications designed for life-support systems, unless a specific agreement is signed between the manufacturer and Mastervolt. Such an agreement will involve further reliability testing of the ChargeMaster by the equipment manufacturer and/or a commitment to perform such tests as part of the production process. Furthermore, the manufacturer must indemnify and hold Mastervolt harmless from any claims arising from the use of the ChargeMaster with life-support equipment.

2.5 Warranty Details

Mastervolt warrants that this product has been manufactured in accordance with current regulations and technical specifications. Use not in line with the guidelines, instructions, and specifications contained in this user manual may damage the appliance or, in any case, cause it not to meet the technical specifications. Such eventualities are not covered by this warranty. The warranty is limited to the repair and/or replacement costs of the product. Costs for labor required for installation or for shipping defective parts are not covered by the warranty.

3 Operation

3.1 Characteristics

The Mastervolt ChargeMaster is a fully automatic battery charger, meaning it remains on under normal circumstances when the AC power system and batteries are connected. The ChargeMaster is suitable for charging the following types of batteries: lead-acid, AGM, spiral, gel, or deep cycle. It also features an automatic input system allowing it to operate worldwide, being compatible with almost any AC power source. It functions seamlessly with both 230V and 120V currents without compromising output current. The three-stage Plus charging method ensures batteries are always 100% charged. However, in some cases, a two-stage charging method may be more convenient. This option can be configured in the setting mode. If an external AC source is connected, the ChargeMaster acts as an AC-DC converter to power DC loads connected to the batteries.

❗ ATTENTION!: Charging voltages suitable for Mastervolt Lithium-ion (MLI) batteries and not necessarily for other Li-ion batteries.

3.2 Display

The ChargeMaster is equipped with a multi-color LED display. Below are the different colors and LED combinations, along with their meanings. The display indicates the current charging method: Float, Absorption, and Bulk.

Figure 2: ChargeMaster Display Operation (Diagram showing LED indicators for ALIM, Current, Error, Battery Type, Charging Mode: FLOAT, 2-step, Wet, Gel/AGM, BULK, ABS)

ALIM LED (NO BUTTON): Green illuminated = ON, Red = standby.

Setting Button: Press the Set button for 5 seconds to enter setting mode (see paragraph 3.3).

3.3 Setting Mode

To enter setting mode, press the Set button for 5 seconds. Subsequently, another LED will flash next to the current parameter. To cycle through parameters, press Set again. To save the selected parameter, press and hold the button for 5 seconds. To keep parameters unchanged, do not touch the button for 60 seconds. To view the next parameter, briefly press the Set button.

❗ ATTENTION!: It is recommended to check the system voltage for high Li-ion charging voltage levels.

3.4 Faults

The ChargeMaster is protected against overloads, short circuits, overheating, overvoltage, and undervoltage. In case of a fault, a segment of the charge bar will illuminate red. The LED position indicates the fault condition. Refer to sections 3.3 and 7.1 for further clarification.

❗ ATTENTION!: The ChargeMaster is NOT protected against:

• Reverse polarity of the DC output,
• Three-phase AC connection at the AC input.

3.5 Three-Stage Charging Algorithm

Figure 3: Three-Stage Plus Charging System (Diagram showing voltage and current curves over time for Bulk, Absorption, and Float stages)

Observe Figure 3. The battery is charged automatically in three stages: BULK, ABSORPTION, and FLOAT. The first stage, BULK, involves the charger outputting 100% current, rapidly charging most of the battery's capacity. The current charges the batteries, and the voltage gradually increases to reach an absorption voltage of 14.4V (Li-ion: 14.6V) or 28.8V (Li-ion: 29.2V) at 25°C / 77°F. The duration of this phase depends on the battery's capacity relative to the charger and how discharged the batteries were initially. The BULK phase is followed by the ABSORPTION phase. Absorption charging begins when the battery voltage reaches 14.4V (Li-ion: 14.6V) or 28.8V (Li-ion: 29.2V) at 25°C / 77°F and ends when the battery is fully charged. The battery voltage remains constant at approximately 14.25V (Li-ion: 14.6V) / 28.5V (Li-ion: 29.2V) at 25°C / 77°F throughout this phase, with the charging current depending on the initial battery discharge level, battery type, and ambient temperature. For a liquid battery, this phase can last nearly four hours; for gel and AGM batteries, about 3 hours. When the battery is fully charged, the ChargeMaster automatically switches to the FLOAT phase. During the FLOAT phase, the ChargeMaster unit switches to 13.25V (Li-ion: 13.5V) or 26.5V (Li-ion: 27.0V) at 25°C / 77°F and stabilizes this voltage to maintain the batteries in optimal condition. Connected DC loads are powered directly by the charger. If the load exceeds the charger's capacity, the necessary additional power will be supplied by the battery, which will gradually discharge until the charger returns to the BULK phase. When the consumption decreases, the charger returns to the normal three-stage charging system operation. Since the ChargeMaster unit is equipped with a three-stage Plus charging system, batteries can remain connected to the ChargeMaster even in winter. Once every 12 days, the charger automatically switches to the absorption phase to ensure proper battery maintenance and prolong its lifespan. The three-stage Plus charging system is also safe for all connected equipment.

Consult paragraph 8.3 for detailed characteristics of the three-stage Plus charging system.

3.5.1 Temperature Compensation Charging

With the installation of the battery temperature sensor, charging voltages are automatically adjusted to temperature deviations.

Figure 4: Temperature Compensation Charging (Graph showing charging voltage vs. battery temperature for 12V and 24V systems)

Observe Figure 4. When the battery temperature is low, the charging voltage increases. Conversely, when the battery temperature is high, the charging voltage decreases. This method avoids problems of overcharging and boiling, thereby prolonging battery life.

3.5.2 Connecting a Second and Third Battery

The ChargeMaster is equipped with three identical outputs. The total output current is divided among these three outputs. For connection, refer to section 4.6.

3.6 Maintenance

No specific maintenance is required for the ChargeMaster unit. Periodically check your electrical system, at least once a year. Faults such as loose connections, burnt cables, etc., must be repaired immediately. If necessary, use a soft cloth to clean the ChargeMaster's housing. Never use liquids, acids, or degreasers.

4 Installation

During installation and commissioning of the ChargeMaster, always apply the important safety instructions. Refer to Chapter 2 of this manual.

4.1 Unpacking

After unpacking, check the contents for any damage. In case of doubt, contact your supplier. Check the identification label (refer to section 1.4) to ensure the battery voltage corresponds to the ChargeMaster's nominal output voltage (e.g., a 24V battery bank for a 24V charger).

4.2 Environment

During installation, the following prescriptions must be observed:

• The ChargeMaster is designed for indoor use only.
• Ambient temperature: 0 ... 60°C / 32°F ... 140°F; (derating above 40°C / 104°F to reduce the temperature of the internal heat sink).
• Humidity: 0-95% non-condensing.
• Mount the ChargeMaster vertically, with the connection cables facing downwards.
• Ensure that the hot air generated during operation can be discharged. The ChargeMaster must be mounted in such a way as to avoid obstructing airflow through the ventilation openings.
• It is prohibited to place objects within a 10 cm / 4-inch radius of the ChargeMaster.
• Do not store the ChargeMaster in the same compartment as the batteries.
• Do not install the ChargeMaster directly above batteries due to potential corrosive sulfur fumes.

4.3 Cables and Batteries

❗ ATTENTION!: The cable and fuse sizes indicated in this manual are examples only. The prescribed cable and fuse sizes may differ depending on local norms and regulations.

4.3.1 DC Wiring

It is important to remember that high current passes through the DC cables. Keep the cable length as short as possible to maintain the highest possible system efficiency. Recommended minimum cable cross-section for battery cables:

Use ring terminals on the cable ends. Terminals must be crimped with a suitable crimping tool. Use the following cable colors for DC wiring, or at least different colors to clearly distinguish the negative and positive battery cables:

Position the positive and negative cables close to each other to limit the electromagnetic field around the cables. The negative cable should be connected directly to the negative terminal of the battery bank or to the ground side of the current tap. Tighten securely. The positive battery cable must be fused and connected to the positive terminal of the battery bank.

4.3.2 AC Safety Ground

❗ ATTENTION!: The ground cable offers protection only if the ChargeMaster's cabinet is connected to the safety ground. Connect the ground terminal (PE / GND) to the chassis or frame.

❗ ATTENTION!: For safe installation, the ChargeMaster's AC input circuit must be equipped with a residual current device (earth leakage circuit breaker).

4.4 Battery Compartment Overview

Figure 5: Battery Compartment Overview (Diagram showing connections: 1. AC Cable, 2. Discharge Cable, 3. 3 positive charge output terminals, 4. 2 MasterBus connectors, 5. Common negative output terminal, 6. Temperature sensor socket)

4.5 Required Material

Ensure you have all necessary parts for ChargeMaster installation:

For further information, also consult Chapter 7 "Ordering Information". It is advisable to include in the minimum tool kit a flat-head screwdriver (1.0 x 4.0 mm) for securing screw terminals, as well as the necessary tools for fixing screws/bolts (Ø 5 mm) to the corresponding sockets to mount the casing to the desired surface.

4.6 Connection

⚠️ PERIL: Entrust installation to an authorized electrician. Before connecting cables, interrupt the AC and DC voltage supply.

❗ ATTENTION!: Short circuits or polarity reversals can cause serious damage to the batteries, the ChargeMaster unit, cable connections, and/or terminals. Fuses between the batteries and the ChargeMaster cannot prevent damage caused by polarity reversal. Damage caused by polarity reversal may be detected by the service department and is not covered by warranty.

❗ ATTENTION!: Cables that are too thin and/or loose connections can cause dangerous overheating of cables and/or terminals. Therefore, all connections must be securely fastened to limit the transition resistance as much as possible. Use correctly sized cables.

NOTE: If the battery temperature is between 15 and 25°C, the battery temperature sensor connection is optional.

4.6.1 Connection Example

The preceding diagram illustrates the general placement of the ChargeMaster within a circuit. It is not intended to provide detailed wiring instructions for any specific electrical system.

Figure 6: ChargeMaster Installation Diagram (Diagram showing AC input with RCD, DC fuse, DC distribution to batteries, MasterBus connection, and temperature sensor connection)

4.7 Step-by-Step Installation

❗ ATTENTION!: Check cable polarity before commissioning: positive connected to positive (red cables), negative connected to negative (black cables).

If all cables are correctly in place, insert the DC fuse(s) of the DC distribution to connect the batteries to the ChargeMaster.

❗ ATTENTION!: During fuse insertion, sparks may be produced due to capacitors used in the ChargeMaster. This is particularly dangerous in poorly ventilated areas; explosions may occur due to the functioning of the unit. Avoid flammable materials nearby.

At this point, the ChargeMaster is ready to operate. After connecting the AC power supply, the ChargeMaster will begin the charging process.

4.8 Removal

To deactivate the Chargemaster, follow these instructions in the indicated order:

1. Disconnect the ChargeMaster's AC power supply.
2. Remove the DC fuses and disconnect the batteries.
3. Disconnect all wiring.

4.9 Storage and Transport

If not installed, store the ChargeMaster in its original packaging, in a dry, dust-free environment. Always use the original packaging materials for transport. Contact your local Mastervolt Service Center for further information regarding the return of equipment for repair.

5 MasterBus

5.1 What is MasterBus?

All devices compatible with MasterBus are indicated by the MasterBus symbol. MasterBus is a fully decentralized data network that facilitates communication between various devices in the Mastervolt system. It is a communication network based on the CAN-bus protocol, which has proven to be a reliable bus system in automotive applications. MasterBus is used as the electrical power management system for all connected devices, such as inverters, battery chargers, generators, and many others. This facilitates communication between connected devices, allowing, for example, the generator to start if the batteries are low. All devices suitable for MasterBus are marked with the MasterBus symbol. MasterBus reduces the complexity of electrical systems by using UTP connection cables. All system components are practically daisy-chained. For this reason, each device is equipped with two MasterBus data ports. As only a few MasterBus cables are needed, installation and material costs are drastically reduced. New devices can be added to the network simply by extending it. This ensures the MasterBus network has a high degree of flexibility for an extended system configuration. Furthermore, Mastervolt offers numerous interfaces, such as Modbus, capable of making non-Mastervolt devices compatible with the MasterBus network. For central monitoring and control of connected devices, Mastervolt offers four different panels that quickly and easily provide complete information on the status of your electrical system. Four different panels are available, from the small 120 x 65 mm LCD display compatible with Mastervision to the MasterView System color panel. All monitoring panels can be used to monitor, control, and configure all connected MasterBus instrumentation.

❗ ATTENTION: Never connect a non-MasterBus device directly to a MasterBus network, as this will void the warranty of all connected MasterBus devices.

5.2 How to Install a MasterBus Network

Each MasterBus device is equipped with two data ports. When two or more devices are connected via these ports, a local data network called MasterBus is created. Follow the guidelines below:

• Place a terminating device at both ends of the network.
• Connections between devices are made using standard UTP connection cables.
• At least one device on the network must have power supply functionality (see specifications). Since all power supply devices are galvanically isolated, using multiple power supply devices is permitted.
• Avoid ring networks.
• Avoid T-connections in the network.

5.3 MasterBus Functions

MasterBus parameters can be adjusted via the MasterBus network (via a remote control panel or a PC interface using MasterAdjust software).

❗ ATTENTION!: Incorrect parameter settings on the ChargeMaster can cause serious damage to batteries and/or connected loads. Parameter adjustment must be granted exclusively to authorized technical personnel.

5.3.1 Monitoring

5.3.2 Alarms

* Refer to section 8.4, Figure 10 for related characteristics.

5.3.3 History

This menu displays total historical readings (read-only).

5.3.4 Configuration

Below are the parameters that can be modified via the MasterBus network, using a remote panel or a PC interface with MasterAdjust software. For further details, refer to the respective user manuals.

Figure 12: Event Data (Diagram showing Input/Output states for On, Off, Copy, Copy Invert, Toggle)

Figure 12 shows the meaning of the event data. Input is a pulse followed by a longer signal (1/0). On changes the state to On at the first signal. Off changes the state to Off at the first signal. Copy makes the state follow the input. Copy Invert makes the state follow the opposite of the input. Toggle changes the status at the first signal and again at the second signal. It is often used in association.

5.3.5 ChargeMaster Event Sources (ChargeMaster as Event Source)

5.3.6 Event Targets (ChargeMaster as Event Target)

6 Troubleshooting

If you are unable to resolve a problem with the help of this chapter, contact the local Mastervolt Service Center. Refer to www.mastervolt.com. Ensure you have the following information readily available for communication with the local Mastervolt Service Center to resolve a problem: Article and serial number (see section 1.4). Firmware version (for MasterView System software).

6.1 Fault Identification Table

7 Technical Data

* Adjustable, refer to Chapter 5 for settings. Specifications subject to change without notice.

7.1 Dimensions

Figure 13: Dimensions in mm (inches) (Diagram showing the physical dimensions of the ChargeMaster unit)

7.2 Characteristics

Figure 14: Charge current vs. input voltage (Graph plotting charge current percentage against AC input voltage)

Figure 15: Charging characteristics with the three-stage Plus method (@ 25°C / 77°F) (Diagram showing voltage and current curves over time for Bulk, Absorption, and Float stages)

Figure 16: Temperature compensation characteristics (charging voltage vs. temperature) (Graphs illustrating the relationship between battery temperature and charging voltage)

8 Ordering Information

Mastervolt offers a wide range of products for electrical systems, AGM and gel batteries, Li-ion, ground power connectors, DC distribution kits, and much more.

9 CE Declaration of Conformity

Manufacturer: Mastervolt

Address: Snijdersbergweg 93, 1105 AN Amsterdam, The Netherlands

Hereby declares that the product:

• 44010250: Chargemaster 12/25-3
• 44020120: Chargemaster 24/12-3

is in conformity with EC directives, specifically the electromagnetic compatibility directive 2004/108/EC. Furthermore, it complies with the following harmonized standards: EN 55014, EN 55022, EN 61000-3-2, EN 61000-3-3, EN 61000-3-11, EN 61000-6-2, EN 60950, EN60335-1, EN60335-2-29, EN 68-2-6 Low Voltage Directive: 2006/95/EC

Amsterdam,

P.F. Kenninck,
General Director MASTERVOLT

Mastervolt
Snijdersbergweg 93, 1105 AN Amsterdam, The Netherlands
Tel.: +31-20-3422100
Fax: +31-20-6971006
E-mail: info@mastervolt.com