Quick Pedal PSU Amp Rating Question

TDubs

I have a pedal that is rated at 15v 0.3A. I had to order a replacement PSU for it and so ordered an exact 15v 0.3A PSU. A 15v 2A PSU has tuned up. Raised this with the store to be told ‘amperage is allowed to be higher’ I know a piece of equipment is only supposed to draw the amount of current it requires from a supply but have also been told that having significantly too much current available can be damaging.

Can anyone confirm either way please?

ICBM

If the supply is properly regulated it’s fine. Modern supplies of that sort of current rating are since they’re switch-mode types which are fairly sophisticated.

The problem is with older unregulated supplies where the correct voltage is only produced when enough current is being drawn, and drawing less results in the voltage being higher, by up to about 50% in extreme cases - it’s the high voltage which is then the risk to the pedal, not the current capacity itself.

There is a more hidden danger with very high-current supplies too, which is that they can be capable of overriding the reverse-voltage protection if it’s just done with a single diode - a lot of pedals are. So make *certain* that the supply is the right polarity, and turn off immediately if the pedal doesn’t seem to power up normally. If it does, it’s correct.

TDubs

Thanks for clearing this up @ICBM I have updated my PSU knowledge!