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Quick Charge notes about Amperage requirements misleading

In the Quick Charge section, it indicates that the Pinecil requires a minimum of 3a to work, which just isn't true.

Many Quick Charge or QC3 phone chargers are not recommended as Pinecil V2 is rated for a minimum of 3 Amps or more to work properly

I'm successfully using a QC2 charger at 9v. The solder tip included with my Pinecil v2 is measures about 6.7ohms cold, which at 9v should result in a draw of only 1.33a. But powered from a QC2 charger at 9v, IronOS reports 10w (~1.1a). This is fine for surface mount caps, etc, but it's unable to maintain the tip temperature when soldering something large like a 14ga braided wire.

I've also successfully used a QC3 charger at 12v. My QC3 charger does have current and thermal limiting built in as well as an 18w max. At 12v, sure enough, IronOS reports 18w and it heats up quick enough for my needs. This is 1.5a. With the supplied tip, the Pinecil can't (due to ohms law!) draw 3a until the supply voltage is at least 20.1v!! At 12v it should be trying to draw ~1.79a (21.5w), so it's possible the advertised over-temp and over-current protection built into my power supply are kicking in. (This is easy to verify using a bench supply + barrel connector and is described in the IronOS documentation. At 12v the bench supply only reports about 1.8a. At 16v about 2.5a. At 20v it finally draws almost 3a. At 24v, it would use more than 3a, but my bench supply current limits there and lowers the voltage to compensate.)

The way this wiki is written makes it sounds like things will break if using any supply that can't provide 3a, but IronOS even provides a setting for maximum average wattage. I can set my bench supply to 24v, 3A and set IronOS to 18w. And I can watch the bench supply's current limit LED blink on/off rapidly while the display reads <1a draw

The reality as the IronOS documentation describes: peak current draw is governed by the tip resistances and the supply voltage. Through pulse-width modulation (turning the tip on/off really fast), software can limit the average current but peak current (every instance the tip is on) is controlled by Ohms law. If a given power supply can't supply the needed current for your tip/voltage, generally the voltage will sag and power will cap at the supply's power limit. This can cause some supplies to overheat (and that's what the Power Limit setting in Iron OS is there to prevent). For other supplies (esp some cheap USB supplies), this voltage sag can cause the supply to shutdown or drop back to 5v. But there's certainly no hard requirement that only supplies providing at least 3a are needed for a functional setup. BobPaul (talk) 16:53, 25 April 2023 (UTC)