Battery Charger Repair

Thread Starter

RodneyB

Joined Apr 28, 2012
697
I have a 12 Volt 10 Amp battery charger which I would like to repair.

The full specifications of the charger can be found at

http://www.powermaster.com.tw/PM-1012F.htm

When I apply 220 Volts to the charger the following happens

1. The LED goes orange and the cooling fan begins to turn.
2. Within a second the fan stops and the LED goes Green.

I have looked for a circuit diagram and failed to find one and not sure if the short circuit circuit is where the fault is

Any assistance will be greatly appreciated
 

Externet

Joined Nov 29, 2005
1,411
From the behavior and the specifications, seems to me it is behaving as it should.
Something as ... at power up, cycles on lights and fan tests and then proceeds to charge if the battery is found healthy. It displays green as it is charged; or there is no battery connected and the voltage rises to 13.7V as of no-load.
But it is just my opinion...

Have you connected a proper battery in not defunct state before plugging it in ?
Can you show/read its user manual ?

The days of 'dumb brute-force chargers' are gone, many people still believes there is always over 14V at the terminals and any battery in any state can have them applied; frequently damaging the charger. The chargers are built with smart protections now.
 
Last edited:

shortbus

Joined Sep 30, 2009
6,987
The days of 'dumb brute-force chargers' are gone, many people still believes there is always over 14V at the terminals and any battery in any state can have them applied; frequently damaging the charger. The chargers are built with smart protections now.
That's been my finding with modern "smart" chargers too. But have had success with a known good battery that was too discharged to charge, by connecting the discharged battery firs to a running car to put enough charge into it so the "smart" charger would then finish charging. Like a "pre-charge" to wake it up.
 

Reloadron

Joined Jan 15, 2015
4,517
My read is that it sees the battery as fully charged:
* LED1: RED
Power On
* LED2: ORANGE
Charging; GREEN
Full charged

That being about how my battery maintainer displays on my motorcycle. Your User Manual also covers:
Instruction of charging procedure
(1) Connect correct polarized clips to battery terminals.
(2) Connect to mains and switch on. Then charging starts – Red (2A) / Orange (3A~12A) LED light.
(3) At green light keep charging for a couple of hours for complete charging.
(4) When charging finished (Green LED), disconnect from mains and remove clips from battery.
(5) Charging can continue in "Float stage" without harming the battery.

Why do you think something is wrong?

Ron
 

Externet

Joined Nov 29, 2005
1,411
Yes, usually if the 12V discharged battery is under -say 9V- (or whatever manufacturer sets the comparator for) the charger will not enable its circuitry.

Forcing some charge to overcome the enabling voltage level tricks the charger to believe the battery is healthy. Same thing happens with Li-ions under 2.5V in a dedicated charger. Have to be pushed past the point somehow else for the charger to accept them.
 

Externet

Joined Nov 29, 2005
1,411
Have never read the instructions of a newer charger, but suspect they are labeled just as 'smart charger'
What the manufacturer misses is instead of a decal saying 'Smart' , it needs one saying 'Will not charge an overdischarged battery, do not insist!' :rolleyes:

I suppose exploded chargers from abuse overfilled warranty claims and industry went to 'smarts' Now they may be having too many warranty claims for 'non-working' chargers. Because the 'smarts' are not explained. Not very 'smart'

The underdischarged batteries can be brought to tricking the charger by raising their voltage pass the limit, with any protected 14, 16 V source for a short time.

Anyway, an abandoned battery is not resurrection prone. If left discharged over 24 hours, will never recover to a reliable performance.
 

Thread Starter

RodneyB

Joined Apr 28, 2012
697
I have read all the comments and advice and will try and answer everything in this reply.

dl324 The battery is relatively new i am using a 12 Volt 7 Ah battery for testing. I have searched the internet and have found no schematics. I have emailed the manufactures but am not holding my breath.

Reloadron I think the charger is faulty as it was connected to a battery with an inverter. After running for several hours the power was restored and the battery charger immediately showed it was fully charged

shortbus and Externet

I have since done the following test.

1. Connected a 21 Watt 12 volt lamp to the battery I am using for testing.
2. After 15 minutes the terminal voltage was 12.3 Volts
3. After 20 Minutes the battery voltage was 12.12 Volts
4. At this stage I connected a Manson DPM-3232 digital power meter to the battery charger +Ve and -Ve terminals. No connected to the battery and the red LED power on was on and the charge indicator LED was Green.
5. After About 30 minutes ( I made a mistake and reset my stop watch) the voltage on the terminals was 11.99 Volts
6. I then connected the Battery charger with the load still connected.
7. The charger started to charge at 6.3 Amps and the Charge indicator light was orange
8 I removed the load and the charge current drooped to 4.3Amps

I now after reading everything above suspect that new battery I bought may either be faulty or had not discharged enough because the charger is working correctly.

I will leave it on charge over night and then do the above test again.

Thank you everyone for your help
 

Thread Starter

RodneyB

Joined Apr 28, 2012
697
Hi

The conclusion is that the battery charger is working perfectly. It fully charged the battery over a 24 hour period. I then put a load onto it and then charged it again.

Everything is working as it should

Thank you for all the advice and help
 
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