THORLABS SPCM A Series, Operation Manual

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SPCMxxA
© 2019 Thorlabs
5.3 Troubleshooting
When attempting to connect an SPCMxxA, no device is found
ð
Check if the SPCM is powered (power supply connected, SPCM switched on, green LED in
on).
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Check the USB connection.
ð
Make sure, that after 1
st
connect of an SPCMxxA the operating system recognized the
device, installed drivers and found the new device ready for operation.
ð
Click in the Device Dialog to "Rescan".
Minimum photon count is < 0
The minimum photon count serves as an error descriptor, see section " Functional Area "
Particularly, this happens if using the free running timed counter mode - if the measurement
speed is too high with regards to the USB data transfer rate, the SPCM internal buffer (max.
4000 bins) overflows and bin counts are lost. In the Graph display this appears as repeated "-2"
counts (see red marked area):
APD over temperature indicated
The temperature control circuit recognized that the actual temperature of the APD exceeded
the set point for more than 0.5°C. Under normal operation conditions this should not happen,
even after long term operation. However, increased beyond 28°C room temperature or incident
to the SPCM thermal radiation can cause overtemperature alert.
ð
Make sure the fan is switched on and operates (rotation and air stream)
ð
Make sure the SPCM heat sink is not covered and that the fan's air stream is not blocked.
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