Lenovo Power Manager correctly reports it as a 65W PSU.
20.2 V potential between inner and outer cylinders. Not that it matters.
The third-party PSU I bought has a detachable tip. It has infinite resistance between tip and ground, regardless of whether it is joined to the PSU cable or not. This would suggest that there is no contact between center pin and earth anywhere.
Lenovo Power Manager reports it as a 90W PSU, while it is actually a 150W unit.
zsero writes:
What is a "normal TP adapter"? 65W?The resistance between the pin and the outside metal is 10K on a normal TP adapter. It is 1.5K on the W520 adapter!
Anyone with a 135W unit around care to make a measurement?
Thanks in advance
/Some guy