Gunson G4138 - User Manual

MULTISTAGE AUTOMATIC
BATTERY CHARGER
INSTRUCTIONS FOR USE
BEFORE COMMENCING CHARGING
Conforms to: BS EN 60335-2-29, BS EN 50081-1, BS EN 50082-1
If you use a battery charger with just the basic features, it may be
adequate for emergency recharging but it may not give full charge or it
may overcharge causing damage.
This charger is a multistage automatic charger with temperature sensor
compensation. It is suitable for all types of lead acid battery, giving long life
and peak performance in summer or winter. It gives the ultimate in
battery care with simplicity of use.
Not suitable for non-rechargeable batteries
• Rapid charging to 100% capacity
• Automatic switching to a gentle standby mode
• Continuous sensing and adjustment of charge condition
• Responsive voltage regulation system
It is therefore ideal for
• Recharging from flat or partial discharge.
• Regular charge / discharge of traction batteries.
• Maintaining a battery in peak condition during storage.
TECHNICAL SPECIFICATIONS
This charger is a multistage automatic charger, suitable for all types of 12 V
lead acid battery. It has a voltage control system with temperature sensor
compensation. This gives continuous sensing and adjustment of charge
conditions to
• Avoid overcharging damage when hot,
• Avoid low charging capacity when cold.
INPUT: 230V 50Hz 100 W. DOUBLE
I
NSULATED
OUTPUT: 12V 4A DC(5.7A RMS) CONTINUOUS
BATTERY 10Ah TO 60Ah RECOMMENDED
FULL OVERLOAD, REVERSE POLARITY
AND THERMAL CUTOUT PROTECTION
PRODUCT / PARTS MADE IN CHINA
REGULATED VOLTAGES:
14.5V CHARGING 13.8V READY AT 20 DEG. C
TEMPERATURE SENSOR COMPENSATION:
- 0.3V PER +10 DEGREES C
CONFORMS TO BS/EN: 60335-2-29, 50081-1, 50082-1
1. PRECAUTIONS
• The battery charger should be stood on a flat, level, non inflammable
surface. Do not obstruct ventilation holes; a dry well ventilated area is
important for correct operation and safety.
• The charger has a safety cut-out which may arc, use only in an area free
from flammable materials and vapours. The charge will become quite
hot when in use, particularly when charging a battery from flat.
• When connecting to or removing connections from the battery, always
ensure that the AC power is off at the mains supply in order to prevent
sparking (faulty batteries can emit explosive gasses even with an
automatic charger)
• If charging a battery while connected to any electrical system, make
sure that all electrical loads are switched off. If the battery is fitted to a
vehicle with an engine/charging system see also section 4/5.
• Do not operate the charger for extended periods in an overloaded
state
. Ensure the charger is operating within its maximum rated charge
before leaving it unattended. E.g. thermal cut-out not operating on a
frequent basis, (this would give an audible click every few seconds).
Ov
erloading ma
y initiall
y occur with a large totall
y flat battery and may
also happen with a faulty battery as it draws a continuous very high
current from the charger. Take particular care if a battery has suddenly
discharged f
or some unkno
wn reason, this may indicate load from an
electrical fault.
• Before disconnecting the battery, check you have codes for audio,
security systems etc or use a Gunson Vehicle Memory Saver to retain
all codes and system settings.
• Battery electrolyte is a corrosive acid. In the event of accidental
contact, rinse repeatedly with plenty of cold water. Always seek medical
attention in cases of eye contact.
• Use only on 12 VOLT LEAD/ACID batteries (includes maintenance free,
gel electrolyte, valve regulated and wet electrolyte types.
See specification paragraph
2. CONNECTIONS
• Make sure the positive (RED) clip is always fitted to the positive (+)
battery connection and the negative (BLACK) clip is fitted to the
negative (-) battery connection
• If the battery is fitted to a vehicle with an engine/charging system –
With the AC power OFF, connect the battery power connection
(usually +) before the GROUND, make the ground connection on the
engine or body away from fuel lines and battery vents. Reverse the
order for disconnection.
• Follow vehicle manufacturers precautions see Section 4)
• A BUZZER IS FITTED FOR INCORRECT CONNECTION WARNING
Note:This buzzer will work even on a battery that appears to be totally
flat but it does actually need a voltage just over 1 volt to operate
Ensure the car is parked safely with the ignition OFF
3. COMMENCING CHARGING
• With AC mains power off, connect the DC output to the battery
(polarity as above)
• Connect to the AC power supply
• Observe the LED display, the charger should now be charging the
battery, indicated by the illumination of the yellow power output and
the red charging mode lights
IMPORTANT Do not leave the charger unattended if the cut-out
operates and continues to trip regularly (an audible click every few
seconds). This should quickly cease as the battery begins to charge.
See section 4/5
• When the battery is charged the charging LED will go out, replaced by
the green READY LED. The output LED may then flicker as the charge
level in the battery is being maintained.
• With the READY LED on, the charger can stay connected indefinitely as
the charger will continue to adjust to hold the ideal storage condition
this provides excellent care for a longer life. DO NOT LEAVE A
FAULTY BATTERY CONNECTED TO THE CHARGER
• When the battery is required for use, switch off at the main AC supply
before disconnecting the charger from the battery.
4
NORMAL CHARGING
• When the charger is initially connected and the AC supply is switched
on, the power output LED and the charging LED should both be ON.
The charger will s
witch to READ
Y when the batter
y r
eaches full
charge. The charger will switch almost immediately to READY if the
battery has been recently charged or it will switch within a few minutes
if the batter
y has been standing idle f
or just a week or two in a fully
charged state.
• If the battery connections are dirty or corroded and do not make a
good contact, the charger may switch to READY mode earlier than
G4138

Summary

Before Commencing Charging

General Safety Precautions

Ensure proper ventilation, disconnect power before connections, avoid overloading, and save system codes before disconnecting.

Battery Electrolyte Handling

Battery electrolyte is corrosive acid. Rinse skin with water and seek medical attention for eye contact.

Connections Procedure

Connect clips to correct battery terminals, ground first for vehicles, and ensure ignition is off.

Commencing Charging

Charging Process Steps

Connect DC output, connect AC power, observe LEDs, and do not leave unattended if cut-out trips frequently.

Charge Completion Indicators

Charging LED turns off, READY LED illuminates. Output LED may flicker for maintenance charge.

Normal Charging

Initial Charging State

Initially, power output and charging LEDs should be ON. Charger switches to READY when full.

Troubleshooting Poor Contact

Dirty or corroded connections may cause early switch to READY mode. Reconnect if issues persist.

Signs and Symptoms

Safety Cut-out Operation

Cut-out operates during early stages of charging a flat battery. Do not charge if it trips excessively.

Battery Capacity Issues

Quick charging from flat may indicate reduced capacity due to age or damage. Poor performance may result.

Gassing and Faulty Cells

Gassing indicates a faulty cell or short circuit. Do not use batteries that gas or overheat.

Testing the Battery

Normal Voltage Readings

Provides expected voltage ranges for charging, ready, and off-charge states for battery testing.

Charger Output Test

Test charger output without battery (approx. 11V). Check power output and charging LEDs.

Load Test Limitation

A 12V tester bulb is not suitable. Use a good battery for testing due to the charger's protection system.

Warranty Information

Return for Service

Details on how to return the product for service or repair, including contact information.

Gunson G4138 Specifications

General

Model	G4138
Type	Battery Charger
Battery Type	Lead Acid
Output Voltage	12V DC
Features	Short Circuit Protection