Made in Germany
NFA1000_4.6_e.doc as of July 2010
- 16 -
© Gigahertz Solutions GmbH
7 Power
Supply
7.1 Internal Rechargeable Battery
The instrument features high performance Lithium Ion rechargeable batteries (2 x 3.7
V). These have a much higher energy density than the normal NiMH rechargeable
batteries, and this without the suspected “memory effect” and comparably low self-
discharge.
Display of capacity
On every change of setting of the „power“ switch the remaining battery capacity will
be displayed as a percentage for a few moments.
To exploit the life expectancy of 250 to 500 complete loading cycles typical for Li-
Ion batteries to the maximum consider the following advice:
There is no need to „condition“ them by cyclical charging and discharging.
The batteries come approximately half full, as this is best for a long life.
Long term storage is best at 50 % capacity and in the fridge, but above
4 Celsius. Recharge them to 50 % every 6 months during long-term storage.
The instrument protects the batteries from being totally discharged when in use.
When not in use or during storage, there is no automatic protection, though. In
this case, a manual recharge up to 50 % is recommended, see above.
Please note, that Li-Ion batteries, even when treated most cautiously, will loose a bit
of their original capacity within one or two years, and, if their full capacity is required,
will have to be replaced after two to three years even if only scarcely used.
7.2 Charging
To charge the battery set the AC adapter to 15 Volts. A parallel measurement is not
possible.
If the battery has been completely discharged, about 80 % capacity will be obtained
after 5 hours (this is best for the batteries’ life-time), and 95 % after 7 to 8 hours of
charging. After reaching full capacity, the charging circuitry will switch off automati-
cally in order to protect the battery. While charging, the charging circuitry generates
fields which are similar to those of energy saving light bulbs. Hence do not charge
on your bedside table!
Suggestion:
In order to optimize the battery’s life-expectancy you can define by NFAsoft,
whether you want the battery to be charged to only 80 % capacity (the optimum for
“normal measurements”)
or whether it is to be loaded to 100 % (necessary only for a
full 48 hours of measurements). After only one hour of charging, the capacity of an
average 9 V alkaline battery is reached.
