Bosch C7 Battery Charger

Introduction

This user manual provides instructions for the Bosch C7 battery charger. The following pictograms and symbols are used:

• ?️ Do not dispose of electrical devices in household waste!
• ⚠️ Observe warning and safety instructions!
• ⚡ Caution: Risk of electric shock! Dangerous electrical voltage - Risk of death.
• ? Explosion hazard!
• ? Fire hazard!
• ?‍?‍?‍? Keep children and other persons away from the battery charger during use.
• ? For indoor use only.
• ? Dust and waterproof (IP65).
• ☣️ Corrosion hazard!
• ? Read the user manual!

Read this user manual carefully and unfold the page with the illustrations. Keep the manual accessible and pass it on if you give the device to a third party.

The Bosch C7 is designed for charging and maintaining 12V and 24V lead-acid batteries (with electrolyte, AGM, or gel). Operate the charger in a well-ventilated area. The device is not suitable for charging lithium-ion batteries. The manufacturer is not liable for damages resulting from improper use. The device is not intended for commercial use.

Scope of Delivery:

• 1 x Charger
• 1 x Power cable with plug
• 2 x Connection clamps (1 red, 1 black)
• 1 x Charging cable with 2 ring terminals
• 1 x User manual
• 1 x Wall mount

Parts Description

The Bosch C7 charger features the following components:

• 1. Charger: The main unit.
• 2. Mounting Hook: For hanging the charger.
• 3. Power Cable with Plug: Connects the charger to the mains.
• 4. Charging Cable with Ring Terminals: Connects the charger to the battery. Includes red and black cables.
• 4a. Fuse: Protects the device.
• 4b. Plug: Connector on the charging cable.
• 5. (+) Pole Connection Clamp (red): Connects to the positive battery terminal.
• 6. (-) Pole Connection Clamp (black): Connects to the negative battery terminal or vehicle chassis.
• 7. Standby/Power Indicator: Shows the device's power status (blue when in standby).
• 8. Mode Selection Button: Used to cycle through charging modes.
• 9. Polarity Protection LED: Illuminates if the battery clamps are connected in reverse.
• 10. Charging Status Indicator: Shows the current charging status.
• 11. Charging Status "OK" Indicator: Lights up when charging is complete.
• Maintenance Charging Indicator: Blinks when in maintenance charging mode.
• 12. Mode 1 LED: Indicates 12V (Motorcycle/Car) normal charging.
• 13. Mode 2 LED: Indicates 12V (Winter, AGM) charging.
• 14. Mode 3 LED: Indicates 12V (Power Supply) mode.
• 15. Mode 4 LED: Indicates 12V (Regeneration) mode.
• 16. Mode 5 LED: Indicates 24V (Truck) charging.
• 17. Mode 6 LED: Indicates 24V (Winter, AGM) charging.

Technical Data

Primary

• Input Voltage: 230 V / 50 Hz
• Inrush Current: < 50 A
• Input Current: Max. 1.2 A (RMS)
• Power Consumption: 135 W

Secondary

• Rated Output Voltage: 12 V, 24 V
• Charging Voltage: 14.4V/14.7V (±0.25 V) for 12V; 28.8V/29.4V (±0.6 V) for 24V
• Charging Current: 7 A (±0.7 A), 5 A (±0.5 A), 3.5 A (±0.35 A), 1.5 A (±0.3 A)
• Rated Output Current: 3.5 A / 7 A
• Ripple 1: Max. 150 mV
• Battery Type: 12 V + 24 V Lead-acid batteries (AGM, GEL, MF, Open, VRLA)
• Battery Capacity: 12 V: 14 Ah - 230 Ah / 24 V: 14 Ah - 120 Ah
• Reverse Current 2: < 5 mA (no AC input)
• Protection Class: IP 65 (dustproof, waterproof)
• Internal Fuse: 10 A
• Noise Level: < 50 dBA
• Ambient Temperature: 0 to +40 °C
• Dimensions (L x W x H): 197 x 108 x 65 mm

Safety

Safety Instructions

• ⚡ Damaged power cables pose a risk of electric shock. Do not operate the device with damaged cables, power cords, or plugs. Have damaged cables repaired only by qualified personnel.
• Do not operate the device with damaged cables, power cords, or plugs.
• Have damaged power cables repaired only by qualified personnel.
• ?‍?‍?‍? Keep children and other persons away from the battery charger during use.
• This device can be used by children aged 8 and above, and by persons with reduced physical, sensory, or mental capabilities or lack of experience and knowledge, if they are supervised or have been instructed on the safe use of the device and understand the resulting hazards. Children must not play with the device. Cleaning and user maintenance must not be carried out by children without supervision.
• ⚠️ Risk of Injury!
• If the battery is mounted in the vehicle, ensure the vehicle is switched off. Turn off the ignition and set the vehicle to park position, with the parking brake engaged (e.g., car) or secured (e.g., electric boat).
• When connecting the charger, use screwdrivers and wrenches with insulated grips.
• ? Explosion Hazard! Protect yourself from a highly explosive hydrogen gas reaction!
• Hydrogen gas (knallgas) can escape from the battery during charging and maintenance charging. Knallgas is an explosive mixture of hydrogen and oxygen gas. Contact with open flames, glowing embers, or sparks triggers the so-called knallgas reaction!
• Perform charging and maintenance charging in a weather-protected area with good ventilation.
• Ensure that there are no open flames, glowing embers, or sparks present during the charging and maintenance charging process!
• ? Explosion and Fire Hazard!
• Do not use the charger to charge dry or non-rechargeable batteries.
• Do not use the charger to charge lithium-ion batteries.
• Ensure that explosive or flammable materials, such as petrol or solvents, cannot be ignited when using the charger!
• The charging connection cable must not come into contact with any fuel line (e.g., petrol line).
• Ensure adequate ventilation during charging.
• Place the removed battery on a well-ventilated surface during the charging process.
• Do not use the charger to charge or maintain a damaged or frozen battery!
• Before connecting to the mains, ensure that the mains supply is properly equipped with 230V ~ 50 Hz, an earthed neutral conductor, a 16 A fuse, and an RCD (Residual Current Device).
• Do not expose the charger to fire, heat, or prolonged exposure to temperatures above 50°C!
• Do not cover the charger during operation!
• Protect the electrical contact surfaces of the battery from short circuits!
• Do not place the charger on or directly next to the battery!
• Position the charger as far away from the battery as the charging cable allows.
• ☣️ Corrosion Hazard!
• Wear safety goggles! Wear protective gloves! If battery acid comes into contact with eyes or skin, rinse the affected area immediately with plenty of flowing, clear water and seek medical attention promptly!
• ⚡ Electric Shock Hazard!
• Never disassemble the charger. An improperly assembled charger can lead to a life-threatening electric shock.
• Perform assembly, maintenance, and care of the battery charger only when disconnected from the mains!
• Only touch the insulated parts of the (-) and (+) pole connection clamps!
• Never touch both connection clamps simultaneously when the charger is in operation.
• Before connecting or disconnecting the charging cable to/from the battery, always disconnect the power cable from the socket first.
• After completing the charging and maintenance charging process, if the battery remains connected to the vehicle, always disconnect the charger's (-) connection clamp (black) from the battery's (-) pole first.
• In case of operating malfunctions or damage, immediately disconnect the charger from the mains!
• Have the charger repaired only by qualified personnel!
• Disconnect the charger from the mains and the battery when not in use!

Product Features

This device is designed for charging open and various types of closed lead-acid batteries used in passenger cars, motorcycles, and other vehicles. This includes WET (with liquid electrolyte), GEL (with gel electrolyte), or AGM batteries (with electrolyte-absorbing mats). Battery capacities range from 12V (14 Ah) up to 12 V (230 Ah) or 24 V (14 Ah) up to 24 V (120 Ah).

The device's special design allows for recharging batteries to almost 100% of their capacity.

The charger features a total of 6 charging modes for different batteries and states, enabling more efficient and safer charging.

Unlike conventional products, the charger offers a special function to recharge nearly discharged batteries. Maintenance Charging: The charger can remain connected permanently to maintain the battery's full charge state. The charger automatically switches to maintenance charging mode after the charging process is complete.

High safety precautions against incorrect use and short circuits ensure safe operation. An integrated circuit ensures that the charger only starts the charging process a few seconds after the charging mode has been selected. This prevents sparks that often occur during the connection process.

Furthermore, the battery charger is controlled by an internal MCU (Micro-Computer Unit).

Operation

Before Operation

• Before connecting the charger, consult the battery's user manual.
• Also, observe the vehicle manufacturer's regulations for batteries permanently connected to the vehicle.
• Clean the battery terminals. Be careful not to get dirt in your eyes.
• Ensure adequate ventilation. Hydrogen gas (knallgas) can escape from the battery during charging and maintenance charging.

Connecting

• Connect the (+) connection clamp (red) (5) of the charger to the (+) pole of the battery.
• Connect the (-) connection clamp (black) (6) of the charger to the (-) pole of the battery.
• The (-) connection clamp (black) (6) can also be connected to the vehicle's chassis, provided it is located away from fuel lines.
• Note: Ensure a secure connection of the (+) or (-) connection clamp.
• Only then connect the power cable to the mains.

As soon as the charger is connected to the mains, it automatically switches to standby mode. The "Power" indicator lights up blue.

Note: The charger features polarity protection. The LED (9) lights up if the (+) or (-) connection clamps (5) (6) are connected incorrectly.

Disconnecting

• Switch the charger to standby by pressing the Mode selection button (8).
• Always disconnect the power cable from the mains first.
• Remove the (-) connection clamp (black) (6) from the (-) pole of the battery.
• Remove the (+) connection clamp (red) (5) from the (+) pole of the battery.

Memory Function

If the device is disconnected from the mains during a charging process, it saves the executed mode. Upon reconnection to the mains with the same battery type (12 V or 24 V), the device automatically starts in the last mode. If the battery type is different (12 V and 24 V), it switches to standby.

Caution: If Mode 2 or 6 (battery in cold condition or AGM battery) was previously used, and then a WET or GEL battery is connected, it can lead to overcharging and damage to the battery. In this case, it is essential to adjust the mode to the battery being charged. No Memory Function for Mode 3 and 4!

Selecting Operating Mode

Press the Mode selection button (8) to select the desired operating mode. The LED for the selected mode will light up.

The following operating modes are available:

Mode 1 | 12 V (14.4V / 7A)

Suitable for batteries with a capacity of over 14 Ah in normal condition. Charging mode for WET and most GEL batteries.

• Press the Mode selection button (8) to select Mode 1. The LED indicator (12) lights up. If no further action is taken, charging will start automatically after a few seconds, and the LED indicator (10) will also light up. After successful charging, the LED indicator (11) lights up, and the LED indicator (10) turns off.
• The device automatically switches to maintenance charging mode after a short time; the LED indicator (11) blinks.

Mode 2 | 12 V (14.7V / 7A)

Suitable for batteries with a capacity of over 14 Ah in cold conditions or for many AGM batteries (with electrolyte-absorbing mats).

• Press the Mode selection button (8) to select Mode 2. The LED indicators (12+13) light up. If no further action is taken, charging will start automatically after a few seconds, and the LED indicator (10) will also light up. After successful charging, the LED indicator (11) lights up, and the LED indicator (10) turns off.
• The device automatically switches to maintenance charging mode after a short time; the LED indicator (11) blinks.

Mode 3 | Support Mode / Power Supply

Suitable for support mode, e.g., when replacing a battery, it is necessary for some vehicles that the vehicle's electronics are not interrupted in their power supply. The C7 can be used to supply power to the vehicle's electronics while the battery is being replaced.

Connecting to a Battery Installed in the Vehicle

• Press the Mode selection button (8) to select Mode 3; the LED indicator (14) blinks.
• Note: In support mode, turn off all electrical consumers (e.g., ignition, radio, lights).
• Note: If the circuit is interrupted, the charger automatically switches to standby mode.
• Caution: Do not charge the battery for extended periods in this mode. The battery can be destroyed.

Power Supply (Mains Adapter)

To use the device as a power supply without a connected battery:

• Press and hold the Mode selection button (8) for approximately three seconds. When the integrated switch engages, the LED indicator (14) lights up. The power supply starts with a current of 13.6V (± 0.25 V) / 5A (±10%).
• Note: Suitable as a power supply for 12 V consumers, e.g., a cool box.
• Note: The charger has an overload protection in this mode (max. 6.0 A).
• Note: There is no polarity protection in this mode (see "Connecting").
• Caution: In this mode, voltage is present at the connection terminals even without a consumer connected.

Mode 4 | Regeneration Mode (16V Boost)

Suitable for regenerating batteries that have been temporarily extremely discharged. The battery should be disconnected from the vehicle's electrical system. For batteries with a capacity of over 14 Ah.

• Press the Mode selection button (8) to select Mode 4. The LED indicator (15) lights up. If no further action is taken, the regeneration mode will start automatically after a few seconds, and the LED indicator (15) blinks. If the battery is almost completely discharged, the LED (15) may blink for up to 3 hours. During this time, a constant current of 1500 mA flows into the battery to restore its performance. After a maximum of four hours, the regeneration mode switches off. If the battery is not yet fully charged, the charger switches to a normal charging mode. After successful charging, the LED indicator (11) lights up, and the LED indicator (10) turns off.
• The device automatically switches to maintenance charging mode after a short time; the LED indicator (11) blinks.
• Note: This mode is only suitable for 12 V batteries.
• Note: The battery must be fully charged in this mode! Do not interrupt the charging process prematurely.

Mode 5 | 24 V (28.8V / 3.5A)

Suitable for batteries with a capacity of over 14 Ah in normal condition. Charging mode for WET and most GEL batteries.

• Press the Mode selection button (8) to select Mode 5. The LED indicator (16) lights up. If no further action is taken, charging will start automatically after a few seconds, and the LED indicator (10) will also light up. After successful charging, the LED indicator (11) lights up, and the LED indicator (10) turns off.
• The device automatically switches to maintenance charging mode after a short time; the LED indicator (11) blinks.

Mode 6 | 24 V (29.4V / 3.5A)

Suitable for batteries with a capacity of over 14 Ah in cold conditions or for many AGM batteries (with electrolyte-absorbing mats).

• Press the Mode selection button (8) to select Mode 6. The LED indicators (13+16) light up. If no further action is taken, charging will start automatically after a few seconds, and the LED indicator (10) will also light up. After successful charging, the LED indicator (11) lights up, and the LED indicator (10) turns off.
• The device automatically switches to maintenance charging mode after a short time; the LED indicator (11) blinks.

Charging Status

The charging status of the connected battery is indicated on the charger as follows:

Visual Representation:

• OK Indicator: Shows charging is complete or in maintenance mode.
• Mode Button: Part of the display.
• Percentage Indicators: 75%, 50%, 25% show charging progress.
• Maintenance Charging: Indicated by a symbol (infinity loop).

Pulse Charging

This is an automatic function of the charger that cannot be selected manually. If, at the beginning of the charging process, the battery voltage is between 7.5 V (± 0.5 V) and 10.5 V (± 0.5 V) for 12 V mode, or between 16 V (± 0.5 V) and 21 V (± 1.0 V) for 24 V mode, the charger automatically switches to pulse charging. When a battery voltage above 10.5 V (± 0.5 V) / 21 V (± 1.0 V) is reached, the charger automatically switches to the previously selected charging mode. This results in better charging.

Device Protection Function

In the following abnormal situations, the charger switches to standby mode:

• Regeneration process > 7 hours
• Charging process > 41 hours
• Battery voltage < 7.5 V (for 12 V batteries)
• Battery voltage < 16 V (for 24 V batteries)
• Open circuit
• Reverse polarity connection

If the polarity is reversed, the LED (9) also lights up. If no other setting is made, the system remains in standby mode.

In case of a short circuit on the charging cable, the fuse (4a) protects the device and the electrical system from damage. If mode selection is not possible, check the fuse (4a).

Overheating Protection

If the device becomes too hot during the charging process, the output power is automatically reduced. This protects the device from damage.

Maintenance and Care

Always disconnect the power plug before performing any work on the charger!

• The device is maintenance-free.
• Switch off the device.
• Clean the plastic surfaces of the device with a dry cloth.
• Never use solvents or other aggressive cleaning agents.

Disposal

For EU Countries:

?️ Do not dispose of electrical devices in household waste!

According to European Directive 2012/19/EU on waste electrical and electronic equipment and its transposition into national law, non-functional electrical tools must be collected separately and subjected to environmentally sound recycling.

The packaging consists of environmentally friendly materials, which you can dispose of through local recycling facilities.

Information

Service

Have your devices repaired only by qualified specialist personnel and only with original spare parts. This ensures that the safety of the device is maintained.

Warranty

You receive a 2-year warranty on this device from the date of purchase. The device has been carefully manufactured and conscientiously tested before delivery.

Please keep your sales receipt as proof of purchase. In case of a warranty claim, please contact your point of sale. This is the only way to ensure free return shipping of your goods.

This warranty is valid only for the original purchaser and is non-transferable.

The warranty service applies only to material or manufacturing defects, not to wear parts or damage to fragile components, e.g., switches. The product is intended solely for private and not for commercial use.

The warranty is void in case of misuse, improper handling, force, or tampering. Your statutory rights are not restricted by this warranty.

Definitions:

• 1 Noise Value: Describes the interference values of current and voltage.
• 2 Reverse Current: The current that the charger consumes from the battery when no mains power is connected.

Available Spare Parts