Hi Jeff,
You may wish to consder one of the PicoLog 1000 series devices, the PicoLog 1012 or 1216 - information on them may be found on our website:
http://www.picotech.com/multi-channel-daq.htmlThe input voltage range is limited to 0 to +2.5V so you may require a resistor to drop the voltage down.
The PicoLog software will allow you to capture the time at which the data is recorded. You may need to sample at 5ms intervals in which case you may have to capture data for less than 24 hours and start recording again as there is a file limit of 1 million samples per channel.
I hope this helps.
Regards,