If anyone can tell me what the power requirement for the dash-mounted clock is in (mA), I would be grateful. JasonAndreas was kind enough to explain how one can measure this, but I simply have not had the time to fiddle with the car.

Thank you in advance for any guidance.

Andreas

 

How many ma just to make the hands go round ?
Or how many ma for every function ?

 

Just for the quartz clock mechanism.

Andreas

 

It has to be really really low... I would think a 50ma ac adapter would do it...

The Porsche battery maintainer puts out 500ma and it has to charge the batt. and keep the computer happy along with the clock.

I know you are probably looking for exact power specs... sorry... hope this helps.

 

Sure, that helps. What is the rule with these figures? In other words, as long as the AC adaptor puts out more in (mA) than the items requires, all is well?

I read somewhere that if the (mA) rating for an AC adaptor is less than the item requires, it can heat up and fail. This is probably common sense, but I'd rather be safe than sorry

Andreas

 

Yes, you need more mA than the clock draws or the transformer will "melt down".
The general rule is to have a 10% buffer... meaning the adapter puts out 10% above the rated power consumption.
To get that close we would need the real specs on the clocks power needs.

I wouldn't be surprised if someone here can get this.
I suspect it is well under even the smallest plug-in AC transformer.

 

Mark,
Thank you. So in this case, bigger is better. Naturally it makes sense to get the transformer's output closer to what the device requires. I'll wait to see if others chime in with an actual (mA) value.

Andreas

 

Do you have a dvm ?

 

The clock current demand should be less than 10ma. The total battery
current demand with the key "off" should be less than 60-80ma max.
Ideally, it should be around 30-40ma for a good cranking battery after
a no-charge (e.g. not running) for a month.

 

Indycam - yes.

Loren - Thank you. PM sent.

Andreas

 

If you remove the cabriolet top warning bulb the approximate draw should be 3.0mA, an unmodified clock should draw 14.0mA. - TSB Group 2, 9204 (March 29, 1994) Diagnosing Discharged Battery and that doesn't include the back-lighting.

 

Thanks for the continued assistance. Any thoughts on where to purchase AC adaptors that have a very low mA rating? I've only been able to find companies that sell adaptors that start at 500 mA.

Andreas

 

"yes"
If you hook your dvm up to your desk clock you should be able to see how many ma its using .

 

"Any thoughts on where to purchase AC adaptors that have a very low mA rating? "
How about a 9 volt battery ?

 

I'd rather employ an AC adaptor and have the clock always function.

Andreas