SV 104A USER'S MANUAL_______________________________________________________
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4
RUNNING AND OPERATING BASIC PROCEDURES
4.1
USB Charging
The battery inside
SV 104A
uses lithium-ion technology which requires special consideration and handling
techniques due to the extremely high energy density (see
“SPECIAL PRECAUTIONS WHEN USING AND
CHARGING LITHIUM BATTERIES
” clause on page 4).
Note that
SV 104A
dosimeter is equipped with an internal charger, so that the fixed internal batteries
can be charged directly from computer USB port or optionally provided charger (
SA 54:
universal micro-USB
charger).
Ensure the
SV 104A
is fully charged prior to use by connecting it to a USB port or to USB charger.
Ensure the power supply is connected and the supply is switched on. The
SV 104A
will automatically turn on
the display during charging and present how much charge is within the instrument. The
SV 104A
will display
‘Fully charged’ once charging is complete. This should take approximately 2 hours from a fully discharged
state. A charging time of about 30 minutes will be sufficient to perform greater than 8 hours of measurement.
A fully charged instrument holds enough charge to run for approximately 48 hours.
Note that once disconnected from USB power supply, the dosimeter will automatically switch off.
If returned to the USB connection or put again onto the docking station the dosimeter keeps trickle charging
regardless of whether or not it is fully charged. This keeps the battery performance in steady condition. If the
battery is fully discharged prior to being placed on a charger, the
SV 104A
trickle charges for a short time prior
to the fast charge cycle, this prevents damage to the batteries.
The number of hours you have used your dosimeter from your last charge will impact total charge time.
For example, if the battery clock indicator displays 40 hours remaining on the battery and you wish to charge
the battery, the approximate charging time is 1 hour.
Note: To charge a fully discharged battery, it would take approximately 2 to 2.5 hours or about
7-7.5 hours when using low power USB interface.
Note: To charge multiple dosimeters at the same time via the USB port, ensure your
computer or possibly the powered USB hub such as the SA 156 or switch is capable in terms of providing
enough current performance. Standard hub or switches without external power supply are not capable to
charge multiple SV 104A dosimeters due to insufficient current supply.
Current estimation: Assume the current consumption on 0.5A level, and calculate required power supply
requirement (N x 0.5A).
Power wattage estimation: With nominal voltage of 5V per USB, the power supply wattage should be 2.5W
per dosimeter (Nx2.5W).
For example, 5 dosimeters charged at once require: 2.5A/12.5W USB power supply
For example, 3 dosimeters charged at once require: 1.5A/7.5W USB power supply
For example, 1 dosimeter charged alone requires: 0.5A/2.5W USB power supply
Note: Use only high quality USB cables, such as SC 156. Many poor-quality cables do not
ensure low resistance of the cable, thus disabling proper charging of the internal cells.
