[RM2488]

Originally Posted by i74js

I think this is tapped at the battery terminals only and no other wiring. When the car is off, it shows the potential difference between two terminals and when the car engine is running, it shows the increased potential difference due to working of alternator.

There can't be special arrangements in these kind of small devices. Please correct me if I am wrong.

Cheers

In fact, there can be- which is why I'm curious. And it appears this device uses it- there are two different buttons to see the battery and alternator voltage. I'm guessing it hooks up between the rectifier and battery charge controller- or else to something that is directly alternator driven.

Or perhaps it hooks up via OBD.

[i74js]

Originally Posted by RM2488

In fact, there can be- which is why I'm curious. And it appears this device uses it- there are two different buttons to see the battery and alternator voltage. I'm guessing it hooks up between the rectifier and battery charge controller- or else to something that is directly alternator driven.

Or perhaps it hooks up via OBD.

No buttons / switches only LED indicators and none of them is glowing (if it is not the fault of the photographor) while the reading of 14 V is there.

I rest my doubts, simple wiring connected to the battery terminals.

Connection through OBD - serious docubts, its bad quality plastic and quite cheap device with seven segment display (no LCD).

Let the owner of this device comment please

[RM2488]

Originally Posted by i74js

No buttons / switches only LED indicators and none of them is glowing (if it is not the fault of the photographor) while the reading of 14 V is there.

I rest my doubts, simple wiring connected to the battery terminals.

Connection through OBD - serious docubts, its bad quality plastic and quite cheap device with seven segment display (no LCD).

Let the owner of this device comment please

You're probably right. Those are not buttons.

Guess: if the voltage at battery terminals (I would guess it plugs into the cigarette lighter port) > 13.5, it switches to 'alternator'.

[kamal.sn]

Originally Posted by RM2488

How is it wired up? As in, the battery voltage is simple... how did you hook it up to the alternator? As far as I know, there are rectifier and control stages between the alternator and battery.

It is connected to the cigarette lighter and measures the voltage at the battery terminals. When the engine is on, the voltage displayed is that of the alternator and when it is off, the voltage displayed is that of the battery.

It is a simple device and serves its purpose.

[JustCause]

Finally, it happened to me

It was raining yesterday and I switched on the parking lights while returning home at about 11am. At about 10pm, I found the lights to be still glowing. Switched off everything and tried cranking this morning. The starter ran lethargically, and died later. The battery is not fully dead as all lights come on and glow bright.

My home UPS has a charging current of 9A while the battery has a Rated Charging current of 2.5A.

Is it a good idea to charge it for an hour or so at 9A and try cranking?

I've already called for the batmobile but it will take a while as it is raining heavily and due to Eid.

[Aroy]

Originally Posted by JustCause

Finally, it happened to me

It was raining yesterday and I switched on the parking lights while returning home at about 11am. At about 10pm, I found the lights to be still glowing. Switched off everything and tried cranking this morning. The starter ran lethargically, and died later. The battery is not fully dead as all lights come on and glow bright.

My home UPS has a charging current of 9A while the battery has a Rated Charging current of 2.5A.

Is it a good idea to charge it for an hour or so at 9A and try cranking?

I've already called for the batmobile but it will take a while as it is raining heavily and due to Eid.

There should be no problem, as the 2.5A charging rate is the nominal rate for long charging duration - 20 hours. In cars the initial charge is quite high and may even exceed 20A for a short duration. Hence charging your battery at 9A for 4 hours will give it about 36*.9 ~ 33AH (0.9 is assumed to be the efficiency factor), well short of the smallest car battery.

Also keep in mind that a smaller capacity battery may not charge at 9A, unless the charges is a constant current type.

[JustCause]

Originally Posted by Aroy

Also keep in mind that a smaller capacity battery may not charge at 9A, unless the charges is a constant current type.

Thanks for your inputs. Exide batmobile guys drove 25 km to get to my place in around 1 hour. Extremely good service. Car started but the battery needs a 4-5 hour charge.I'm hooking up the UPS to the battery now.

[saket77]

Originally Posted by JustCause

Thanks for your inputs. Exide batmobile guys drove 25 km to get to my place in around 1 hour. Extremely good service.

Would like to know about the Exide Batmobile? Seems like on-road service by Exide, but please divulge the details. Is it chargeable/ available to other than Exide customers, etc?

[archat68]

Originally Posted by saket77

Would like to know about the Exide Batmobile? Seems like on-road service by Exide, but please divulge the details. Is it chargeable/ available to other than Exide customers, etc?

It is a free of cost service. Applicable to *ANYBODY*. Call them up at 3271 1111 (prefixed by your city STD code).
http://www.exidereachout.com/about-u...batmobile.aspx

[saket77]

Originally Posted by archat68

It is a free of cost service. Applicable to *ANYBODY*. Call them up at 3271 1111 (prefixed by your city STD code).
http://www.exidereachout.com/about-u...batmobile.aspx

That is an excellent intiative; I didn't know that it's free and available to even non-exide customers. Its really helpful as its available in my city too. Hope the execution part is available here too!

Thanks,
Saket

[lapis_lazuli]

Hi all,

Today, as part of my monthly under the hood check, I noticed the following:

1) The terminal voltage of the battery is 12.2V. It is an Exide, 12V 45AH, for the Punto. It is about 18 months old. (Car engine OFF. No user controllable items ON.)

2) When I start the car, and leave it at idling, the terminal voltage is 14.5V. I guess the alternator is OK.

Are these healthy figures, especially, the one in (1) ?

(Multimeter is fairly accurate)

Regards

[saket77]

Originally Posted by lapis_lazuli

Hi all,

Today, as part of my monthly under the hood check, I noticed the following:

Yes, Lapis. They are perfect figures: 12.2 V.

On the alternator, it can be anything in the range of 13-15 Volts.

You can test it by going a step forward, purely for your interest. Switch on the headlamps and rev the engine a bit. You should still get +13V.

Are you facing any issue with the electronics?

[lapis_lazuli]

Originally Posted by saket77

Are you facing any issue with the electronics?

Thanks Saket. No issues at all, except, sometimes, may be once in 3-4weeks, the car would fail to start at the first crank. Need to crank once or twice more, after a gap of a few seconds. Mine's a petrol, so much less demanding!
But, I was expecting something in the range of 12.5+ (at 2.1V/cell at optimum charge). If you say its OK I will go by it

The experiment you suggested: I will give it a try. It makes perfect sense!

[saket77]

Originally Posted by lapis_lazuli

Thanks Saket. No issues at all, except, sometimes, may be once in 3-4weeks, the car would fail to start at the first crank. Need to crank once or twice more, after a gap of a few seconds. Mine's a petrol, so much less demanding!
But, I was expecting something in the range of 12.5+ (at 2.1V/cell at optimum charge). If you say its OK I will go by it

The experiment you suggested: I will give it a try. It makes perfect sense!

Lapis, surely its not a new battery. 12.6V is the output of a 100% charged healthy battery- Open circuit. Most likely the battery when you tested was hooked to the car's terminals. Hence, there was some standing load on it like the ECU/ Music system and resistance of some wires too. Even in that case, your battery should be holding around 70% of charge. Also, the ambient temperature can affect the reading.
A more pointing test can be the specific gravity check which can be done at a battery shop. Would hardly take 5 mins of time.

Regards,
Saket

[ramzsys]

They gave a 'health sheet' from Ford during my last service, in which battery CCA was mentioned.

What am i to infer from this data?