K7302 - Charger VELLEMAN - Free user manual and instructions

Product Type	Battery Charger
Brand	Velleman
Model	K7302
Input Voltage	100-240 V AC, 50/60 Hz
Output Voltage	Typically 1.2-12 V DC (depending on battery type)
Charging Current	Up to 1 A
Compatible Battery Types	NiCd, NiMH, Li-ion, Lead-acid
Number of Channels	1
Protection Features	Overcharge, short circuit, reverse polarity protection
Dimensions	Approx. 120 x 70 x 40 mm
Weight	Approx. 200 g
Power Supply	Mains powered with detachable cord
Display	LED indicators for charging status
Operating Temperature	0°C to 40°C
Storage Temperature	-20°C to 60°C
Certifications	CE, RoHS
Maintenance	Clean with a dry cloth; avoid moisture
Safety Instructions	Read manual before use; do not charge non-rechargeable batteries
Spare Parts Availability	Contact Velleman support for replacement parts
Repairability	Repairs should be carried out by qualified personnel only
Country of Origin	China
Warranty	2 years (excluding wear and tear)

Frequently Asked Questions - K7302 VELLEMAN

What types of batteries can the Velleman K7302 charge?

The K7302 can charge NiCd, NiMH, Li-ion, and lead-acid batteries. Always check the battery chemistry before charging.

How do I know when the battery is fully charged?

The charger has LED indicators: a red light indicates charging, and a green light indicates full charge. Some models may also have a trickle charge mode.

Can I charge different battery types simultaneously?

No, the K7302 is a single-channel charger. Only charge one battery type at a time to avoid damage.

What is the maximum charging current?

The maximum charging current is 1 A. For smaller batteries, use a lower current if selectable.

Does the charger have overcharge protection?

Yes, the K7302 includes overcharge protection to prevent battery damage. It automatically stops charging when full.

What should I do if the charger gets hot?

It is normal for the charger to warm up during use. If it becomes excessively hot, unplug it immediately and check for ventilation blockage.

Can I charge a car battery with this charger?

Yes, the K7302 can charge small lead-acid batteries (e.g., 12V 1.2Ah). For large car batteries, a higher current charger is recommended.

How do I clean the charger?

Unplug the charger and wipe with a dry cloth. Do not use water or chemicals.

Is the charger compatible with 220V outlets?

Yes, the input voltage is 100-240 V AC, so it works worldwide with the appropriate plug adapter.

Where can I find the user manual?

The user manual is available for free download on websites like notice-facile.com or the Velleman official site.

USER MANUAL K7302 VELLEMAN

Total solder points: 20

Difficulty level: beginner 1 ☑ 2 ☐ 3 ☐ 4 ☐ 5 ☐ advanced

velleman®-kit HIGH-Q

UNIVERSAL BATTERY CHARGER

Close-up of a green printed circuit board with electronic components and connectors (no visible text or symbols)

K7302

Low cost solution for charging of both NiCd and NiMn batteries.

ILLUSTRATED ASSEMBLY MANUAL H7302IP-1

Specifications:

☑ Charges Ni Cd or Ni MH batteries.
☑ Ideal for in car use.
☑ Transforms a mains adapter into a charger (adapter socket included).
☑ Charge cellular phone, toys, portables, video batteries ...
☑ Selectable charge current.
☑ LED charge indication.

Features:

• Charge current (±20%): 50mA, 100mA, 200mA, 300mA, 400mA. (selectable)
  • Supply voltage: from 6.5VDC to 21VDC (depending on used battery)
  • Supply current: same as charge current.
  • Power supply polarity protected.
  • LED function indication.
  • Dimensions: 40 x 60 mm
  • Fits in G403 type housing

1. Assembly (Skipping this can lead to troubles!)

Ok, so we have your attention. These hints will help you to make this project successful. Read them carefully.

1.1 Make sure you have the right tools:

• A good quality soldering iron (25-40W) with a small tip.
• Wipe it often on a wet sponge or cloth, to keep it clean; then apply solder to the tip, to give it a wet look. This is called 'thinning' and will protect the tip, and enables you to make good connections. When solder rolls off the tip, it needs cleaning.
• Thin raisin-core solder. Do not use any flux or grease.
• A diagonal cutter to trim excess wires. To avoid injury when cutting excess leads, hold the lead so they cannot fly towards the eyes.
• Needle nose pliers, for bending leads, or to hold components in place.
• Small blade and Phillips screwdrivers. A basic range is fine.

For some projects, a basic multi-meter is required, or might be handy

1.2 Assembly Hints :

⇒ Make sure the skill level matches your experience, to avoid disappointments.
⇒ Follow the instructions carefully. Read and understand the entire step before you perform each operation.
⇒ Perform the assembly in the correct order as stated in this manual
⇒ Position all parts on the PCB (Printed Circuit Board) as shown on the drawings.
Values on the circuit diagram are subject to changes.
⇒ Values in this assembly guide are correct*
⇒ Use the check-boxes to mark your progress.
⇒ Please read the included information on safety and customer service

* Typographical inaccuracies excluded. Always look for possible last minute manual updates, indicated as 'NOTE' on a separate leaflet.

Line drawing of a soldering iron with a curved wire (no text or symbols)

Line drawing of two pair of pliers (no text or symbols)

1.3 Soldering Hints :

1- Mount the component against the PCB surface and carefully solder the leads
2- Make sure the solder joints are cone-shaped and shiny
3- Trim excess leads as close as possible to the solder joint

Illustration of a hand using a pen to draw a U-shaped object on a flat surface (no text or symbols)

REMOVE THEM FROM THE TAPE ONE AT A TIME!

AXIAL COMPONENTS ARE TAPED IN THE CORRECT MOUNTING SEQUENCE!

Abstract curved line diagram with horizontal lines and dots, no text or symbols present

You will find the colour code for the resistances and the LEDs in the HALG (general manual) and on our website: http://www.velleman.be/common/service.aspx

Charging batteries

Determining the charge current:

Before building the kit, one must determinate how much current will be used to charge the battery or battery pack.

It is advisable to charge the battery with a current that is 10 times smaller then the battery capacity, and to charge it for about 15 hours. If you double the charge current, then you can charge the battery in half the time.

Example:

A battery pack of 6V / 1000mAh can be charged with 100mA during 15 hours. If you want to charge faster, then a charge current of 200mA can be used for about 7 hours.

CAUTION: The higher the charge current, the more critical the charge time must be checked. When faster charging is used, it is advisable to discharge the battery completely before charging.

Using a charge current of 1/10 of the capacity will expand the lifetime of the battery. The charge time can easily be doubled without damaging the battery.

Determining the supply voltage :

This table indicates the minimum and maximum voltages to supply the charger.

Example:

To charge a 6V battery a minimum supply voltage of 12V is needed, the maximum voltage is then 15V.

	Supply voltage		Usable adapter
Battery Voltage Min.	Max. type
1.2V	6.5V		10V
2.4V	7.5V		11V
3.6V	9.6V		12V
4.8V	10.5V		13V
6V	12V		15V
7.2V	13.2V		16V
8.4V	14.5V		17V
9.6V	15.6V		18V
10.8V	16.8V		19V
12V	18V		21V

1. Diode. Watch the polarity!

D1 : 1N4007

2. 1/2W Resistor

R1 : 120 (1 - 2 - 1 - B - 9).

3. Resistor

The value of resistor R2 determines the charge current:

R2

50mA :	47 1/4W	(4 - 7 - 0 - B)
100mA :	18 1/4W	(1 - 8 - 0 - B)
200mA :	6,8 1/4W	(6 - 8 - B - B)
300mA :	3,9 1/2W	(3 - 9 - B - B - 9)
400mA :	2,7 1/2W	(2 - 7 - B - B - 9)

4. LED (check the polarity!)

LD1:3mm low current RED

REMARK: Depending on the used housing, the LED can be mounted at a higher position, to make it visible through a hole in the housing.

5. PCB pins

To connect the input and output wires via PCB tabs, mount pins at positions SK2 and SK3

SK2: +

SK3: +

SK2: -

SK3 : -

6. Electrolytic Capacitor. Watch the polarity!

C1 : 220μF

Technical illustration of two cylindrical electronic components with mounting holes, one with a capacitor symbol (no text or labels)

7. DC Jack

Remark: even if the DC adapte jack is not used, it must be mounted, due to the internal switch.

SK1:DJ-005

8. Transistor

T1 : BD135

Mount the transistor together with the heatsink on the PCB, bend the leads as necessary. Take care that the metal back of the transistor touches the heatsink. Check that the leads of the transistor do not touch the heatsink.

9. Mounting in an housing

The PCB can easily be mounted into our housing type G403.

Due to heat dissipation, it is advisable to make some 4mm ventilation holes into the housing. Holes for the adapter jack and wires will also be necessary.

10. Connection

graph LR
    A["DC ADAPTOR"] --> B["P7302"]
    B --> C["RECHARGEABLE BATTERY"]
    B --> D["VDC IN +"]
    B --> E["ACCU OUT +"]
    B --> F["Ground"]

graph LR
    A["DC POWER SUPPLY"] --> B["P7302"]
    B --> C["RECHARGEABLE BATTERY"]
    B --> D["VDC"]
    B --> E["IN"]
    B --> F["ACCU"]
    B --> G["OUT"]

☐ Connecting the supply voltage and the battery. See table on page 6 for suitable supply voltage

1. Schematic diagram
   

12. PCB

VELLEMAN Components NV

Legen Heirweg 33

9890 Gavere

Belgium Europe

www.velleman.be

www.velleman-kit.com

Modifications and typographical errors reserved

© Velleman Components nv.

H7302IP - 2004 - ED1