Hi,
I've just got a Crust Crawler 6 DOF and having searched through my collection of wall warts I found one with 7.5VDC 2.5A on the case. Long story short, I went to test the voltage on the jack and I'm reading just over 12V. Any reason for this difference?
I'm assuming that it's not safe to power the arm with.......
TIA,
Michael
Or try loading it slightly - 10Kohm across them and I normally find they drop to a fairly acceptable level.
I think that is most likely to work with a switching regulator style wall-wart. If it is big/heavy, it is likely to have just a transformer and rectifier inside and relies on the rated current to drag the voltage down to the rated value.
Pete
If there are spikes that might do something. You need a 3 ohm resistor to get 2.5 amps. Figure up to a 30% voltage increase on a normally cheapo supply. A good unregulated supply can get a 10-15% regulation. Regulated packs are so cheap and reliable, and low RF noise, that I buy them from Jameco all the time.
greg
Have something to add? Share your thoughts — no account required.
Ask the community — no account required