13
FREQUENTLY ASKED QUESTIONS
Q.
When charging batteries what should I observe?
A.
If you want to see what’s going on then go to the CALIBRATION screen and you will be able to observe the
“Charge mA”.
With a relatively flat set of batteries when you first start charging you should observe a constant current of
around 22
0mA and “CHG” will be displayed (and a similar message on the MAIN screen). It will stay this way
for some time until the charging system switches to constant voltage. When this happens you should observe
the Charge mA slowly dropping. Eventually, when the mA drops below the
“Charge Full mA” preset (see
SETTINGS) the charging will cease and “OFF” will be displayed. At this point the MAIN screen will display
“FULL”. The charger disconnects from the batteries completely (DC pass-through), no trickle charging.
Q.
Why does the charge current suddenly drop to 0mA from 200mA+ when I am charging the batteries in the
PDVS2mini?
A.
The Lithium-Ion PP3 batteries are charged in series, as are the two cells within each battery. It is important for
successful charging that the batteries are the same capacity & type and have the same capacity of charge in
them before trying to charge them. Failure to do this can mean the internal protection circuit of one of the
batteries can detect a possible over charge and shutdown. The symptom of this is that when you are charging
batteries within the PDVS2mini that it suddenly stops charging and the charge current drops to 0mA.
To fix this, remove the batteries from the PDVS2mini and charge them separately in a standalone charger.
This will match them again and you can return them to the PDVS2mini.
If this problem persists then you may have a faulty/weak battery.
Q.
Can I run the PDVS2mini without any batteries fitted?
A.
You can, but depending on the accuracy and stability you are looking for on the output it’s not recommended.
External DC supplies can sometimes generate noise and ground loops into a system. Running on batteries
negates this.This is also true when running with batteries and with the external DC Input connected.
Q.
What power source can I use to charge the batteries?
A.
Using the DC connector (tai
l) supplied you can use any electronic linear bench power supply that’s capable of
at least 250mA. Just set it to 20Vdc. At this voltage you can also run the unit permanently off the bench power
supply. You can safely run it like this with the batteries installed because once the batteries fully charge the
charging circuit becomes disabled.
It is strongly advised to be very careful when using wall plug type power supplies since especially the linear
type can output a much higher voltage than is printed.
Also, it is advised not to use wall type switch mode type power supplies as these can be notoriously noisy.
Q.
Is there an Apple or Linux version of the PDVS2mini Windows app?
A.
Unfortunately not, I am only able to write code for the Windows desktop. However, the ascii based serial
protocol is available on request if you want to write your own.
Q.
There’s a blob of sealant on my Pcb covering some components?
A.
This isn’t a quality issue, but is infact protecting the DAC filter components from possible humidity issues.
The sealant used is non-corrosive and designed for electronics.
Summary of Contents for PDVS2mini
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