Reply by legg June 7, 20182018-06-07
biwecity currently has multiple listings for a 36V Li-Ion battery 
charger. One example is item 322458751129. All have the same 
listing illustration and description as a 42V 2A charger for 
110-240VAC input:

An observant purchaser could probably note irregularities in the 
product's labeling, but this is not unusual in off-shore sourced 

Unfortunately, the items shipped may not even resemble the image 
being evaluated:

The shipped device is actually a ~27W charger built around a 
typical applications circuit using the Kintago KTG7838 off-
line controller IC:
Actual load profile is characteristic of the application circuit:

As constructed, it cannot even be guaranteed to start up 
below about 140V, due to the device's start-up current spec 
and the selection of trickle-feed resistor value.

The unit tested here actually failed during the record (the 
zeros in the table and graph), with the chip assuming a low 
fixed impedance on it's supply pin.

If what you need is an ~80W device, don't bother with this one.

I'm sure that the seller, biwecity offers some excellent deals 
on other components, but they are unable to deliver on this one.