Rebody Pingu's Kit Car Project

Pingu

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I've found the battery drain. It's the "Veglia" clock. 60mA. Doesn't seem very much, but there is already a 75mA background drain, so the extra 60mA makes it an excessive 130mA. That's enough to drain the battery to about 50% in a fortnight.


I've thought of several options

  1. A second battery
  2. A simple switch that I use to switch the clock on and off
  3. Get a clock that uses less current
  4. Connect the clock to the radio or the ignition circuits
  5. A set-up that switches off the power to the clock when the voltage drops below a certain level

  1. Not practical.
  2. If I forget to flip the switch to off, the battery will go flat.
  3. I would need to find one that I can butcher, and I would need to butcher the "Veglia" one.
  4. I would need to reset the clock EVERY time I use the car.
  5. This would be some sort of Zener diode set-up.

I'm going to go with option 5. I may need to use the Zener as the switch for a transistor, but I may get away with just using the Zener diode on its own. Wish me luck. o_O
 
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Zephyr

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No idea of what a Zener is, but you sound so scientific and full of confidence that I really think this will work. Good luck. (Googling Zener now).
 

Pingu

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No idea of what a Zener is, but you sound so scientific and full of confidence that I really think this will work. Good luck. (Googling Zener now).
A Zener diode is a diode that allows current to flow when the voltage is higher than a certain level. So, a 12v Zener diode will allow current to flow as long as the voltage is above 12 volts.
 

jaguartvr

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Worth asking ETB about the drain. It does seem to draw too much, they may have a solution or there could be a fault with the clock.
 

Pingu

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Worth asking ETB about the drain. It does seem to draw too much, they may have a solution or there could be a fault with the clock.
I've spoken to ETB, and he confirms that its a characteristic of the clock. He thinks the Zener may work.

Zeners have a ±5% tolerance, so I'll need to test each one in the £2.99 pack of ten to see which one is best.
 

Piran

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Oct 21, 2022
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9
I've found the battery drain. It's the "Veglia" clock. 60mA. Doesn't seem very much, but there is already a 75mA background drain, so the extra 60mA makes it an excessive 130mA. That's enough to drain the battery to about 50% in a fortnight.


I've thought of several options

  1. A second battery
  2. A simple switch that I use to switch the clock on and off
  3. Get a clock that uses less current
  4. Connect the clock to the radio or the ignition circuits
  5. A set-up that switches off the power to the clock when the voltage drops below a certain level

  1. Not practical.
  2. If I forget to flip the switch to off, the battery will go flat.
  3. I would need to find one that I can butcher, and I would need to butcher the "Veglia" one.
  4. I would need to reset the clock EVERY time I use the car.
  5. This would be some sort of Zener diode set-up.

I'm going to go with option 5. I may need to use the Zener as the switch for a transistor, but I may get away with just using the Zener diode on its own. Wish me luck. o_O
Could you not get a rechargeable battery which you charge when the ignition is on and run the clock from that - when off it just uses the battery for the clock (so 1 in your list but use a small rechargeable?)
 

Pingu

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Could you not get a rechargeable battery which you charge when the ignition is on and run the clock from that - when off it just uses the battery for the clock (so 1 in your list but use a small rechargeable?)
Yes, but 60mA is lots. I reckon that four 10,000Ah 3.7v powerpacks would last about 8½ days. A second 12v 80Ah battery, just to run the clock would last less than two months.

The only solution is to switch the clock off when the engine is not running. The only question is how long do I leave the clock running after I switch the engine off. At the moment, I'm planning to switch the clock off when the battery voltage drops below 12volts.
 

MisterP007

German-Italian-British Mix - What could go wrong?
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Remove the power from the Veglia/ETB clock permanently. At least it will be correct twice a day! =))

No idea why i am laughing as mine also drains down in a couple of days if not run. I have not investigated the voltage drop yet but could be the clock (ETB/Veglia) or i also suspect the audio sub below the seat wired for power into the old electric seat wiring (i am going to remove this over the weekend and eBay it as I never listen to music anyway, the exhaust is glorious so why bother!).

Have fun.
 

Pingu

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Remove the power from the Veglia/ETB clock permanently. At least it will be correct twice a day! =))

No idea why i am laughing as mine also drains down in a couple of days if not run. I have not investigated the voltage drop yet but could be the clock (ETB/Veglia) or i also suspect the audio sub below the seat wired for power into the old electric seat wiring (i am going to remove this over the weekend and eBay it as I never listen to music anyway, the exhaust is glorious so why bother!).

Have fun.
IT IS the clock. The Zener diodes arrived today. I'm just about to go up stairs and start playing with my variable voltage supply. I may get distracted by my train set, though :ymdevil: .
 

IanA

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Oxon
I use solar power battery "chargers" on cars I don't use frequently.
I also have Bluetooth battery monitors so I don't even have to open the boot.
 

MisterP007

German-Italian-British Mix - What could go wrong?
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I use solar power battery "chargers" on cars I don't use frequently.
I also have Bluetooth battery monitors so I don't even have to open the boot.
Tell us more with the links to where to get them please!
 

MisterP007

German-Italian-British Mix - What could go wrong?
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IT IS the clock. The Zener diodes arrived today. I'm just about to go up stairs and start playing with my variable voltage supply. I may get distracted by my train set, though :ymdevil: .
Train-sets, at your age?

Say's me with my hi-fi and camera obsession. Just sitting down to photograph all my spare and vintage cameras and some older hi-fi gear eBay is beckoning. So far adds up to £2500 just sitting in boxes and cupboards. Taking all my old vinyl to a local shop tomorrow probably another £1500 sitting there. May have to get onto the CD's next another £1000 of those all never used.

Hobbies, who needs them?
 

IanA

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I got the 100W solar chargers and the monitors from eBay.
 

Pingu

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IT IS the clock. The Zener diodes arrived today.
Looking at google tells me that it is much more than just sticking a Zener diode in series with the load.

I've just spent £15 getting together enough electronics to last me a few more years.

I could have bought a module for £5.50, but where's the fun in that?

 
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