vacana

i planning to make a voltmeter and ammeter for this power supply, i will step down the output voltage from the power supply and step up the voltage from the shunt resistor using two opamps configured as differential amplifier. is the -1.3v from the power supply enough for the meter opamps? i will use tle2141 for the meter.

which would be a good AC input fuse value for a 115V country?