MCA527
The remaining battery life time is sufficient to transfer the measured spectrum to a
computer. It is recommended, before reading out the MCA527, to connect it to an external
power source.
In the case that the battery voltage drops below its lowest value, the battery itself switches
off. This can be, for example, the result of a lasting short circuit at the preamplifier power
supply. As a consequence the internal setup and the measured values are lost. The
MCA527 has to be connected to an external charger to recharge the battery.
2.2.4 Charging the MCA527
Charging the MCA battery is usually done by connecting the wall adapter to the power
input connector and power it from the mains supply. The wall adapter is able to deliver
enough power to operate the MCA527 stationary under a maximum load condition (HV
on, detector draws up to 2W preamplifier power). If the MCA527 is operated on a high
power USB hub and the wall adapter isn’t connected, it can be charged from the USB
port. But there is a limitation of 2,5W nominal input power which is the maximum power
that can be drawn from a high power USB port (real usable input power depends on hub
voltage, voltage loss on USB cable and connectors and efficiency of internal charger; it is
usually about 2W). This is enough power to operate the MCA527 without detector or with
a low power detector (e. g. CdZnTe or NaI). If a detector draws to much power from the
MCA527 (e. g. some HPGe), charging via USB is still working but the battery runs out
slowly.
There are two different variants of behavior when the MCA527 is connected to a working
high power USB hub. Each variant has advantages and disadvantages. The variant is
hard coded within the MCA527.
Variant 1:
Charging keeps switched off when the MCA527 is connected to a working high
power USB hub. This saves the laptop battery from potential discharge, however, the
MCA battery will be potentially emptied.
Variant 2:
Charging is started after 6 seconds automatically when the MCA527 is
connected to a working high power USB hub. This saves the MCA battery from potential
discharge, however, the laptop battery will be potentially emptied. One advantage of this
variant is that a MCA527 that battery is fully discharged can be operated without a wall
adapter.
Since the most users prefer the first variant, it is the standard variant. It is however
possible to get the second variant on request.
It is possible to enable or disable USB charging by newer application programs such as
WinSPEC. Connecting the wall adapter to the MCA527 and supply it with power will
always turn off USB charging.
The old battery chargers supplied with the MCA166 (3 pin LEMO connector) or
the MCA166-USB (2 pin LEMO connector) are not compatible with the MCA527!
Don’t try to connect them to the MCA527. The connectors are mechanically
different.
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