(Apologies for copy and pasting this into a new thread but I was getting no replies)
I was in Maplin yesterday all ready to buy a power supply, only to be confused by the variety on offer.
They nearly all had selectable voltages. So that was ok
But they had different current settings. some 300mA , some 900mA, some 1200mA. Which is best? Or does it not matter? Which current should I try to get as close to?
Also could someone clear up the issue of whether these power supplies convert the UK mains AC to a DC output? If so is this what I want? Or do I need one that keeps the power at an AC output because the x0x will change it to a DC ? I'm confused about this. As I understand it I need to feed an AC into the x0x so any power supply that converts to DC is not much usefull. Or am I totally wrong?
Thanks..
Ian
Current for power supply?
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- controlvoltage
- Posts: 242
- Joined: Tue Aug 09, 2005 12:17 am
The "official" (US Robotics) power supply for the x0x is rated for 500 mA of current... at least, mine is. There is a thread on this forum where the current usage of the x0x is specified in excruciating detail. As I understand it the current rating on a powersupply simply means that it is good for devices which draw less than or up to the rated current. So, you want a power supply that is putting out 9V AC (not DC of any sort) and is rated for 500 mA, minimum... if you find one that has a higher current rating, it won't hurt to use it although don't pay extra for higher current rating if you are only going to use the adaptor for the x0x, as it would be wasted capacity in that case....
the only possible problem with too high of a current rating
for the 9v ac adapter
is that it might produce too high of a voltage
as current is drawn off of a wallwart
the voltage output drops
so to make a higher current rating they just up the voltage
so if youre purchasing your own wallwart
make sure that the voltage across c8 does not exceed 30v
for the 9v ac adapter
is that it might produce too high of a voltage
as current is drawn off of a wallwart
the voltage output drops
so to make a higher current rating they just up the voltage
so if youre purchasing your own wallwart
make sure that the voltage across c8 does not exceed 30v
-
- Posts: 12
- Joined: Thu Oct 13, 2005 5:29 am
Power supply
Hi,
lol...yes Maplin is confusing sometimes!!
I bought the:
500mA Variable Voltage AC/AC plug top adaptor.
made or supplied by sunpower
www.sunpoweronline.co.uk
cost about £8
However I haven't used it yet as I've been too busy to get on with building my x0xb0x so far.
Hope that helps
Ian
lol...yes Maplin is confusing sometimes!!
I bought the:
500mA Variable Voltage AC/AC plug top adaptor.
made or supplied by sunpower
www.sunpoweronline.co.uk
cost about £8
However I haven't used it yet as I've been too busy to get on with building my x0xb0x so far.
Hope that helps
Ian
Please be positive and constructive with your questions and comments.