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Appendix B: Trouble Shooting Guide
Power Supply Issues
For reliable operation the camera input supply must be 12 V to +24 V DC.
The power supply to the camera should be suitably current limited as per the applied input voltage
of b12 V to +24 V. Assume a worst case power consumption of 24 W and a 150% current
rating for the breaker or fuse. Note that the camera will not start to draw current until the input
supply is above approximately 10.5 V and 200 msec has elapsed. If the power supply stabilizes in
less than 200 msec, then inrush current will not exceed normal operating current.
It is important to consider how much voltage loss occurs in the power supply cabling to the
camera, particularly if the power cable is long and the supply is operating at 12V where the current
draw is highest. Reading the input supply voltage as measured by the camera will give an
indication of the supply drop being experienced.
The
camera tolerates “hot” unplugging and plugging.
The camera has been designed to protect against accidental application of an incorrect input
supply, up to reasonable limits. With the following input power issues, the status LED will be OFF.
•
The camera will protect against the application of voltages above approxi28 V. If
the overvoltage protection threshold is exceeded, then power is turned off to the camera’s
internal circuitry. The power supply must be recycled to recover camera operation. The
input protection circuitry is rated up to an absolute maximum of +30 V. Beyond this
voltage, the camera may be damaged.
•
The camera will also protect against the accidental application of a reverse input supply up
to a maximum of -30 V. Beyond this voltage, the camera may be damaged.
Causes for Overheating & Power Shut Down
For reliable operation, the camera’s f
ront plate temperature should be kept below +65
°
C and the
internal temperature kept below +70
°
C.
Many applications, such as in clean rooms, cannot tolerate the use of forced air cooling (fans) and
therefore must rely on convection. The camera’s body has been designed with integrated heat fins
to assist with convection cooling. The fins are sufficient to keep the camera at an acceptable
temperature if convection flow is unimpeded. The camera also benefits by conducting heat away
via the front plate into the lens extension tubes and camera mount. It is therefore important not to
restrict convection airflow around the camera body, especially the fins and the lens assembly and
camera mount. Lowering the ambient temperature will equally lower the camera’s temperature.
If the camera’s internal temperature exceeds
+80 °C, then the camera will partially shut down to
protect against damage.
Commands can still be sent to the camera to read the temperature, but the image sensor will not
be operational and LVAL in response to line triggers will not be generated. Additionally, the
camera’s power will reduce to approximately
+
70% of normal operation. If the camera’s
temperature continues to rise, at +90°C the camera will further reduce it power to approximately
30% of normal operation and any communication with the camera will not be possible. The only
means to recover from a thermal shutdown is to turn the camera’s po
wer off. Once the camera
has cooled down, the camera data can be restored by re-applying power to the camera.
