Wednesday, December 30, 2015

buoy power failure

This is a back-dated post describing what was known about a power failure at the CWDR1 buoy at the end of 2015. The buoy was deployed on December 10th and lost power just under three weeks later on December 30th. It remained offline for a period of about three months.

The buoy's loss of power on December 30th was preceded by three shorter outages: three hours offline on December 26th, thirty hours from December 27th - 28th, and six hours on December 29th.

The following is an excerpt of an email message that I wrote on December 28th, shortly after the buoy had come back online after the 30-hour outage:
The buoy became unreachable yesterday morning at about 5:30am Miami time (6:30am Dominican time).  It remained unreachable for roughly 30 hours before connecting again some time in the last hour.

However, this was NOT simply a failure of cellular service.  The buoy appears to have been entirely non-operational during this time.  When NOAA reestablished contact, we downloaded all data records that had been created in the intervening time, and we can tell by their record numbers whether our downloads are complete.  Our downloads are complete, but record timestamps jump from UTC 10:50 yesterday to UTC 16:40 today.  This applies to datatables in both dataloggers, Met and Main.

I can't quite explain this, except if perhaps there were a temporary power failure to all systems.  But I don't know what kind of power failure could be remedied except through direct intervention, and I would guess that one day offline is not enough time (especially at this time of year) to be noticed, much less to prompt some kind of boat visit.

The Main datatables that are copied from the Met datatables are now full of duplicated records, which is an artifact of the dual-datalogger programming, and another sign that a power failure might be the cause.

I don't know that I would suggest any immediate action in response but I am curious whether anyone knows anything about this buoy's testing.  Now that I think of it, I remember looking over its pre-deployment data and having to edit out a lot of duplicate records, indicative of power ups and downs like this one.  I just assumed that the buoy's power systems were being manually connected and disconnected in that period, as things were moved around.

There were seven such duplications, now that I look at the pre-deployment records more carefully.  The oldest was Nov 12th, and they continue Nov 22nd, 27th, 28th, 29th, Dec 1st, and Dec 5th.  If these are not traceable to times when the buoy's power systems were intentionally cut by human hands, then this might indicate some kind of power problem that could be expected to cause more intermittent outages.
In retrospect I will note that all four of these power outages (as short as 3 hours and as long as 3 months) began at the same time of day, sometime in the hour after UTC 1000 (approximately 6am local time), which could relate to the time of local sunrise.

A subsequent posting on this maintenance log will discuss what what is known about the buoy's return to power.

Thursday, December 10, 2015

Deployment

The Catuan Wreck (Boca Chica) CREWS buoy was deployed on December 10, 2015. Its coordinates are said to be:
18° 25.924' N
69° 34.802' W
The following photographs were supplied to me by Juan Salado of ONAMET, Dominican Republic.





(posted by Mike Jankulak)