Hi guys,
I have just taken delivery from FastTech of this item:
It should have been shipped with the power adaptor but was not. Does anyone know what is the output voltage of the AC power adaptor? FT takes at least one day to respond. Thanks
A quick search on Aliexpress showed an input of DC5.5V so I guess 5V should be working fine.
Yeah, an output of 5VDC is usual.
Also from FT, the one below looks the same but has 12VDC output. Is this for a different gadget?
http://www.fasttech.com/products/1421/10002716/1201200-dc-12v-1a-100-240v-ac-power-adapter
Oh no!
I made a mistake…Reviewing my order, this is the product that I ordered (no power adaptor-type):
It says input 100-240V AC. So if I have an AC line connected to a 5.5mm male connector, I can directly connect it to its 5.5mm female input port?
Not an expert in these things, but I seriously doubt that you can hook that directly to mains (110-240) voltage. The ML-103s appear to be the same. (Other variants have gotten different numbers.) I’d think it’s a copy/paste problem.
At the bottom of this charger, written are DC 5V. and below that is 4.2V. So I guess it needs a power adaptor with a 100-240ACV input with a 5VDC output to power it?
Do you have a soldering iron? If you add a usb jack or usb wire you could use any AC usb adapter.
Or just buy a USB to DC 5.5mm cable. Tmart has one, even cheaper on ebay.
I have been using a 6.5 volt adapter on mine for several months with no problems.
Well, I just tried my Pila’s power adaptor, (6VDC out, same 5.5mm barrel) and it’s working fine.
I was just trying to make sure…I was doubtful of FT’s website voltage figures, and indeed it’s not accurate
Thanks to you all
The charging chip in the Miller ML103 is tp4057.
They actually claim the tp4057 can take 4.5V-15V but its a tiny chip & pcb probably doesn’t have enough heatsinking.
I wouldn’t go much higher then 6.5 since its more its likely to drop the charging current to keep from overheating the higher you go.
Also you can’t absolutely trust the tp4057 specs, its a chinese clone of LTC4057. For one the charge curve that tp4057 claims is not true, it doesn’t match testing.
HKJ’s Review: ML-102 Charger (same tp4057 chip as ML-103)
So to be safe I will just limit the input voltage between 4.5 to 6.5VDC? Will using a 6.5V input yield a higher terminal voltage charged to the cell than on a 5V?
It should be fine & safe at 6.5v. Terminal voltage should be the same (~4.2v) regardless of input voltage. 
No worries.
I was just commenting that I personally wouldn’t trust it at the higher end of 4.5-15v. Like 9v for example. I haven’t tested it or anything.
It should be safe anywhere 4.5-15v. Voltage over 5v would be converted into heat in the two tp4057 chips. It should safely manage the heat by just reducing the charging current (resulting in longer charge time).
I have a laptop charger/power adaptor with an output of 12VDC, also I my C9000 power supply at the same voltage. Problem is, has anyone tried it?
Using 6.5 volts, mine terminates at 4.2v, and almost finished at 4.18v All ok.