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Georgen Guru Joined: 13/09/2011 Location: AustraliaPosts: 462
Posted: 03:44pm 05 Sep 2012
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Have a solar powered meter
(Had a look inside and battery is actually capacitor, small one 1F, 5.5V and my very first capacitor as means of stored power, unless there are other capacitors that I don’t know about)
(It can be charged from 12 – 36V DC battery and 250V AC mains should it run out of charge in the evening)
It has 2 fuses one is 315mA and the other one is 10A
315mA looks like a good choice as it measures 200mA current.
Not too sure regarding the 10A one, as meter measures up to 10A current, so small overloading and it goes.
Looking at the other one (315mA) being good 60% over-rated for the 200mA measurement.
Shouldn’t the 10A be actually 15A to give some room before it blows?
(Looks that I recycle parts of this picture a lot)
George
Wombat Regular Member Joined: 27/05/2011 Location: AustraliaPosts: 72
Posted: 07:09pm 05 Sep 2012
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Hi George,
I have a few 9V battery powered meters and find they can become inaccurate
when the battery gets low. Have you found this with yours?
As for the 10A fuse, I always carry spares. You will find they will take 12-15A for a short time before they blow due to there hysteresis curve.
If you increase them to 15A, I'm sure you will damage the meter.
Russ.
Georgen Guru Joined: 13/09/2011 Location: AustraliaPosts: 462
Posted: 01:15am 06 Sep 2012
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Hi Russ,
I didn't see any strikingly wrong results to question accuracy when "low battery" sign was flashing.
Few times had screen blank, when I left it running overnight by mistake.
Couple of minutes in sunshine makes it work again.
I think I leave it baking is the Sun for too long, only because I don't want it to run out of power.
Would be great if meter had some kind of indicator how much power there is, like my rechargeable shaver that has 20% red LED and 4 green ones for 40%, 60%, 80% and 100%
Thanks for advice on fuse.George
Georgen Guru Joined: 13/09/2011 Location: AustraliaPosts: 462
Posted: 03:20pm 16 Sep 2012
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Got 10 fuses of each at JayCar.
Also found fuse wire 10A and scraped caps of the blown fuse, so have now something like material for few hundred fuses, as I only need 32 - 35mm of wire to repari blown fuse.
Didn't look for 315mA fuse wire, as this one seems to 'last longer'George