Redarc LFP1225, LFP1225-LV, LFP1240, LFP1240-LV User Manual

In-vehicle 12V LiFePO4

Battery Charger

LFP1225, LFP1225-LV,

LFP1240 & LFP1240-LV

THE LFP1225(LV) & LFP1240(LV)

The LFP series In-vehicle Battery Chargers feature technology designed to charge your Lithium
Iron Phosphate (LiFeP04) batteries to their optimal level, regardless of their size. By providing
a unique charging profile, the LFP series In-Vehicle Battery Chargers are able to achieve and
maintain an optimal charge in your auxiliary battery, at all times.
The LFP series In-vehicle Battery Chargers also feature a Maximum Power Point Tracking (MPPT)
solar regulator, allowing you to deliver the maximum amount of power from your solar panels to
your auxiliary battery.

WARNING & SAFETY INSTRUCTIONS

Do NOT disassemble the LFP1225(LV)/LFP1240(LV) - the internal circuitry contains hazardous
voltages.Attempting to service the unit yourself may result in electric shock or fire and will void
the unit warranty.

Do NOT use the LFP1225(LV)/LFP1240(LV) to charge non-rechargeable batteries.
Doing so may result in harm to the user and/or damage to the LFP1225(LV)/LFP1240(LV)

This appliance is not intended for use by persons (including children) with reduced physical,
sensory or mental capabilities, or lack of experience and knowledge, unless they are supervised
or have been instructed on how to use the appliance by a person responsible for their safety.
Children should be supervised to ensure that they do not play with the appliance.

Only use the LFP1225(LV)/LFP1240(LV) for charging REDARC approved Lithium Iron Phosphate
type 12V batteries that feature an inbuilt battery management system with under and over voltage
protection and cell balancing functions.

Check the manufacturers data for your battery and ensure the maximum voltage of the
LFP1225(LV)/LFP1240(LV) does not exceed the manufacturers recommended maximum charging
voltage.

Ensure that the battery management system is capable of allowing the battery to be charged with
25A for the LFP1225(LV) or 40A for the LFP1240(LV). Please contact REDARC if you are unsure if
your battery is compatible.

The LFP1225(LV)/LFP1240(LV) will achieve best results when proper battery maintenance is
regularly performed.

SAL.FOR.Instruction Manual.LFP - DOC952 – Version 2

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CONTENTS

Table of Contents Page

Warnings and Safety Instructions 01
Contents 02
Specifications 02
1 Product Function 03

1. Display Panel 03

2. Charging Algorithm 04

3. Turn On/Off Thresholds 04

4. Error Codes 05
2 Installation 05

1. RED wire - Input Source Positive 05

2. BLUE wire - Source Select 06

3. ORANGE wire - Not Used 07

4. BROWN wire - Auxiliary Battery Positive 07

5. BLACK wire - Common Ground 07

6. GREEN wire - Optional External LED Indication 07

7. Cable Sizing 08

8. Wiring 08

9. RK1260 Relay Kit 11
3 Troubleshooting 12
4 Frequently Asked Questions 13
5 Two Year Warranty 14

Specifications

Part Number LFP1225(LV) LFP1240(LV)
Continuous Current Rating 25A 40A
Input Fuse Rating 40A (Not Supplied)
Output Fuse Rating

Output Power 375W 600W
DC Input Voltage Range 9-32V (9V-16V for LV models)
Solar Panel Open Circuit Voltage 17.5V-28.0V
Battery Type LiFePO4
Constant Current Stage Voltage level 14.6V
Constant Voltage Stage Voltage level 14.5V
No Load Current <100mA
Standby Current <8mA
Ambient Temperature -20°C to +80°C
Minimum O/P Battery Volts 4.2V
Weight 680g
Dimensions 150x120x37mm
Warranty 2 years
Standards CE, C-Tick, AS/NZS CISPR11:2004

REDARC FK40
recommended

60A (Not supplied)

REDARC FK60
recommended

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1 PRODUCT FUNCTION

CHARGE MODE

12V 40A DC/DC
LiFePO4 type
battery charger

LFP1240

Designed and made in Australia

Battery Charger

CHARGE STATUS

Designed and made in Australia

The LFP1225(LV)/LFP1240(LV) is a two stage, 12V DC-DC battery charger that operates
from an alternator input of 12V nominal or a 12V nominal solar panel input. The LFP1225/
LFP1240 will also charge from an alternator input of a 24V nominal vehicle*1. The input
voltage of the LFP1225(LV)/LFP1240(LV) can be above, below or equal to the output
voltage making it ideal for charging an auxiliary 12V battery where the distance from the
main battery may cause a significant voltage drop. The LFP1225(LV)/LFP1240(LV) is also
designed to isolate the main battery from the auxiliary battery, to avoid over-discharging
the main battery.

1.1 Display Panel

The front panel features 2 LEDs to display the charge mode and charge status.

LED State ‘Charge Mode’ LED ‘Charge Status’ LED

Off Unit has no Power Output is off

Blinking Unit is in Standby

On Unit is on and can supply power

Unit is supplying power

When blinking, the flash duty-cycle of the ‘Charge Status’ LED will increase to
reflect the amount of current being supplied - If the LED is ON solid, the unit is
supplying full power (e.g. 25A for a LFP1225).

Figure 1.6.1 - The LFP1225(LV) and LFP1240(LV) Front Panels

*1 LV Versions not suitable for use in 24V vehicles

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1 PRODUCT FUNCTION

1.2 Charging Algorithm

When the LFP1225(LV)/LFP1240(LV) is turned on, it will move into the

Current

stage. This stage maintains a constant current until the battery voltage
reaches its set point. The current may vary during operation in order to maintain
safe operating temperature, or to limit the difference between input and output
voltage.
The charger will then move to
on the output battery, keeping the battery topped up. This stage also counteracts
the battery’s self discharging. When a load applied to the battery causes it to lose
charge, the charger will move back into the

1.3 Turn On/Off Thresholds

Input
Open Circuit
Low voltage

conditions *

Input
Loaded Low

voltage

conditions*

Turn ON above 13.2V 12.0V 17.5V 26.4V

1

Turn OFF below 12.7V 11.9V 17.2V 25.4V

Turn OFF

instantly below

Turn OFF after

2

20 secs below

Constant Voltage

12V

LFP1225 &

LFP1240

LFP1225-LV &

9V N/A 18V

stage. This stage maintains 14.5V

Constant Current

12V

LFP1240-LV

8V 17V

stage.

Solar

All Models

(standard)*

Constant

24V

LFP1225 &

LFP1240

3

Turn ON below 15.5V 28V 32V

Input
Over voltage

shutdown

Output

Under voltage

shutdown

*1Tested every 100 Seconds.
*2 Constantly tested.

*3 LV Versions not suitable for use in 24V vehicles

Turn OFF

instantly above

Turn OFF after

20 secs above

16V 29V 32.5V

15.6V 28.2V 32.1V

Shutdown if Output Battery < 4V

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