GBS Elektronik MCA166-USB - Manual (Page 8)

MCA166-USB
2.2.3 Charging the MCA166-USB
Charging the MCAs battery is usually done by connecting the wall adapter to the ”Charger
In” connector and power it from the mains supply. The wall adapter is able to deliver
enough power to operate the MCA166-USB stationary under a maximum load condition
(HV on, detector draws up to 2W preamplifier power). If the MCA166-USB is operated on
a high power USB hub and the wall adapter isn’t connected, the MCA166-USB 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 MCA166-
USB without detector or with a low power detector (e.g. CdZnTe or NaI). If a detector
draws to much power from the MCA166-USB (e.g. some HPGe), charging via USB is still
working but the battery runs out slowly.
If the MCA166-USB is connected to a working high power USB hub, charging will start
after 6 seconds automatically. It is possible to disable USB charging by some newer
application programs such as WinSpec. This is very useful if the MCA is operated at a
laptop computer which runs on battery. Connecting the wall adapter to the MCA166-USB
and supply it with power will always disable USB charging.
The old battery chargers supplied with the MCA166 (3 pin LEMO connector) are not
compatible with the MCA166-USB! Don’t try to connect them to the MCA166-USB. The
connectors are mechanically different.
2.2.4 Connecting the MCA166-USB to a Computer
Communication between MCA166-USB and host computer is possible via a standard
serial connection (RS232) or via USB interface. For RS232 communication the RS232
cable with SUB-D9 connector must be connected between the MCAs PC-socket and the
computer, for USB communication the special USB cable with LEMO connector must be
used respectively. Two baud rates can be used for communication on both interfaces,
38.400 Baud and 307.200 Baud. Both baud rates are usable on both interfaces but most
computers doesn't support 307.200 Baud on the RS232 interface. The firmware of the
MCA166-USB is able to detect the baud rate and changes it accordingly. Newer
application programs tries to connect the MCA with the higher baud rate first, if it doesn't
work they try it with 38.400 Baud. This method guarantees that communication always
works on the highest possible baud rate without user interaction and maintains
compatibility to older MCAs (supporting only 38.400 Baud). Because the firmware of the
MCA166-USB is able to detect the baud rate, it is also possible to control this MCA with
older application programs which support only 38.400 Baud.
Running the MCA166-USB on a Palmtop computer or Pocket PC is principal possible but
needs a special communication cable. Please contact GBS-Elektronik for availability. For
proper wiring see Table 5: Wiring Diagram of the PC Interface Connector (female Lemo
0S-306) on Page 21.
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