Hi, the battery is inside the preamp.
The external power supply is just there to charge the battery, and it connects the preamp to AC ground (assuming that is the way you have set the jumper inside the preamp).
You can disconnect the power supply completely and the preamp will work (until the battery dies).
Be careful that this approach is not accepted by Dartzeel!!
The following are my previous inquiries about the Dartzeel factory and their answers:
Q1: Battery issue:
1>Whether the main unit is powered on or off, the PSU must be always turned on and cannot be turned off. right?
2>Can I turn off the PSU power while listening to music?
3>When the main unit is fully charged, and the PSU is also turned on, the main unit will keep for about 30 hours(the middle light is orange) .Then automatically turn off (the middle light is red),is this normal?
4>I believe that the new machine I purchased may be stored in the dealer's warehouse for at least 3- 4 years without use. Does this affect the stability and life of the battery? Or I need to ask the dealer to replace me with a new set of batteries.
A1:
1.It is better to always leave the PSU powered ON. Powering PSU off for longer than a single day may damage internal battery if repeated often.
2.This is not necessary to turn the PSU during listening sessions:
a.When batteries are full enough, I mean when the central LED is yellow, special optical communication between the preamp
and the PSU actually lifts all AC connections from AC wall,
exactly the same as if you would power the PSU off.
b. When batteries are empty and need to charged again, the
internal optical communication reactivates internal relays in
order to allow the charge; during charge, the PSU is physically
connected to AC, and the battery is then acting as
powerbuffer during the charge process.
3.This is not easy to say, so the reason why we updated the
firmware version. In this new version, central LED, when preamp
is off, behaves as follows:
a. Central LED is yellow, indicating a charge.
b. When battery is about 75-80% charged, central LED goes
green, for about 1-2 hours.
c. When charge is completed, then the central will completely go
off.Until you will have the new firmware installed, we cannot
make an accurate diagnostic of your battery.
4. When stored for a long time, there is special battery state, called
"SLEEP mode", in which batteries can be stored for a very long time.
Hope this information is helpful to you!!