Tuesday, December 10, 2013

To the beach, for work, honest!!!

Last week i went to Castlepoint beach with technician Sam, this beach is one of my favorites and i have some great childhood memories here, i also spent my birthday here and blogged about the beach / holidays and tsunami risk in April.

On this day though we were here to fix the cGPS (continous GPS), so we turned away from the beach and went up onto Castlepoint Station farm.

After a bumpy ride we were up on top of a hill, with a great view, at the site. This site 'CAST' is a combined cGPS and seismic site, so we get earthquake information as well as ground deformation information.

We had stopped receiving data from the GPS part of this site, and our monitoring system 'Big Brother' told Sam it was due to a broken Net RS.

Old yellow RS and the new Grey R9
 So Sam had brought out a shiny new Net R9 (latest model) to replace it. The Net R9 is a GPS reciever, it gets the data from the GPS and then sends it back to us at GeoNet HQ.  

After swapping the instruments Sam discovered that the site was still not receiving data, so it was investigation time!

Sam investigating

He discovered that water had gotten into the conduit that takes the cable from the cGPS to the receiver, this had then caused a short and killed the Net RS, the water had also caused the lightning arrester to corrode and stop working.

Now usually when our team go and check on sites they take a box of spare bits! Unfortunately, due to unforseen events <read:memory lapse>, this box was still in the lab back at the office!  But being good kiwis we made do and got it back up and running!

So to start with Sam created a drain hole in the conduit and got to removing the water in there -  a really fun job as you can see in the pic below ... 
High-tec water removal method
While i cleaned the lightning arrester with a hairclip!

Sam then replaced the special waterproofing tape on all the joins and everything was back up and running.

This is only a temporary fix to get the data coming back in, so next time one of our technicians are in the area (we have a tsunami gauge out here too) they can replace the cables and pipes, for a more long term fix.
Lightning Arrester

No comments:

Post a Comment