@sync:
The suply stays in both positions in high voltage mod.
At the time I baught it, the maximum was 15.9V, now its 17.4
The low voltage range delivers the same voltage like the high voltage range but the CV and the CC mode LED are in this mide both dark.
My (full working) E3610A goes up to 17.57V in the high voltage mode and the output stays stable at this voltage from 0A to 2.1A (when the current limit kicks in).
On the low voltage mode it depends on the load:
15.5V no load
13.7V @ 1A
12.5V @ 2A
11.2V @ 3A
And the output is not clean. It has ripple. It's basically unregulated.
On my E3610A (and my actual mains voltage) the low voltage mode is usable up to 10V @ 3A. But HP/Aglient only guarantees that it will work up to 8V. This is how these power supplies are designed.
That both CV and CC LEDs glow can happen when the voltage is set higher that the power supply really can deliver (low voltage mode).
To check your E3610A you should make tests with different loads like above.