Thank you for your help.
I am using a CR23x and loggernet. I am using pyranometer and temperature data for a weather station. I am experiencing a critical error and cannot get the CR23x to connect with my computer.
I wired the 5V output to power a microcontroller and the 12V output to drive a small stepper motor. Upon attaching the last wire to the 12V output there was a spark. The data logger displayed error message 13, "low 5V power". A multimeter showed 5V and 12V output was around .7V. When I attempted to connect the data logger to the computer, the computer could not communicate with the data logger because of a critical error. The error message read, “communications with the station have failed” and said “Classic::CmdClockSet.”
How can I remedy this problem? I can use external power supplies for the microcontroller and motor if necessary. My question is: How can I get the CR23X working and communicating with the computer properly? Is the communication error related to the low 5V power error? Thank you.
The 5V External power supply is also used to power the RS232 port. If it has been damaged and is no longer providing power then you will struggle to communicate with the logger through any interface.
If you have not done so already disconnect your connections to the 5V and 12V outputs. The 12V output in particular has a thermal fuse that will reset once any load is removed.
If the 5V is still low it is possible you have either damaged a protective zener diode built into the logger or burnt out a ground track. Either of those problems will require a factory repair although any data in the logger should still be recoverable as long as your ask for this up front.
Thank you for the quick reply. The data logger has been sent in for repairs.
I would like to know what went wrong and how I can avoid this in the future. I am surprised that I was able to critically damage the device accidently. Why are there not more robust overcurrent and overvoltage protections?
Any insights/advices would be greatly appreciated. Thank you.
The 12V output terminal has a 1.85A thermal fuse that cuts out if too high a current is drawn. It will reset when the load is removed so it is normally not possible to damage it.
The 5V output has a transzorb component connected across it to clamp fast transients and prevent damage to the power supply components in the datalogger. However if you connect a voltage much higher than +10V to that output by accident for a prolonged period the transzorb will overheat as it is trying to clamp the voltage to ~<7V to prevent damage. The transzorb is then designed to go short circuit so it continues to give some protection and hopefully blow a fuse somewhere. The transzorb needs to be replaced once it has gone short.
One futher failure state that can happen in combination with these is that if a high voltage is connected to the 5V output for a very prolonged period which causes the transzorb to short the current flowing can burn out a ground rail track associated with the 5V supply.
Generally we do not see many of these problems if a Campbell power supply is used as we take the precaution of adding a 3.5/5A thermal fuse in the output of the supply to prevent accidental shorts etc doing damage, although as thermal fuses take some while to trip you can still do some damage if unlucky.