I happen to own two android devices, a Huawei P30 Pro and a Samsung Galaxy Tab S5e. Both devices came with a charger, the specifications can be seen here
I'd like to charge both devices with one charger, is this safe to do and which one should I use? Does it make a difference?
Both tablets support fast charging, which means they are capable of charging faster than the earlier standard USB charging of 5V,2A.
"Samsung uses "adaptive fast charging", while Huawei uses "super charging". They are proprietary technologies of respective OEMs, with specifics not made public (how fast can your device charge has become a selling point) . OEMs always advise that one uses the charger supplied with the device only, because fast charging is a complex interplay between the charger, device, battery level and cable. Using them interchangeably is not recommended. It's not likely to cause an explosion or something like that if you use the same charger but it would not charge with the same speed as designed. If this is fine with you, I would suggest using Samsung charger for both devices since it has a lower maximum power rating (approximately 15 Watts = 9V x 1.67A) compared to Huawei rating of 40W (10V x 4A).
However, if fast charging is not a priority , it is perfectly safe if you charge at 5V,2A. To do this, you would need to buy or use an old 5V 2A charger from pre-fast charging era and use that for both devices. It will charge much, much slower. Alternatively, see if Huawei P30 has a setting to disable fast charging (Samsung devices have this option from Android 6.0 onwards). I couldn't find it on internet but it may well be available. You can disable fast charging on both devices and use any of these two chargers to charge both devices safely.
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