While there are many unique environmental monitoring applications and sensor/mooring configurations, all buoy deployments require attention to detail to proceed smoothly and with minimal issues. The checklist below discusses basic items to check vital to the stability and longevity of any NexSens buoy system:
- Clean and greased O-rings must be present on all threaded connections to the buoy. Check the following:
- All equipped X2-CB or iSIC-CB blank port plugs and each port receptacle must have an o-ring present
b. Each sensor cable connection must also have a clean plug (and receptacle if applicable) o-ring.
2. Verify that all sensor and plug port connections are dry and that none of the 8-pin connectors or sockets are bent, corroded, or moist.
3. Check that all sensor and plug port connections are hand-tight- any time a new connection is made and periodically during deployment, re-check all connections are secure.
4. For iSIC-CB buoys with RTU-x telemetry units, check the following:
a. The two interior o-rings are making continuous contact with the surrounding enclosure around the entire unit.
b. The COM port receptacle o-ring is in place and the blank plug o-ring is properly seated in its groove.
c. When tightened, the blank plug o-ring is not warped (as shown in the following image), and remains seated with the plug.
Data Logger Vent
5. Most iSIC/X2-CB buoy data loggers manufactured in March 2017 or later will have a removable cap protecting the equipped vent from impact damage. Verify that this vent is secure, clean, and void of any cracks. Any damage to the vent risks water intrusion into the sensitive logger electronics and system batteries housed below.
6. Verify that the any solar beacons are securely tightened down to the solar tower plate using a 9/16″ socket.
7. Verify that the solar tower plate is securely tightened down to the top of the solar tower using a 9/16″ socket.
8. Verify that any deployment pipes (912M, 914M- if equipped), are securely tightened to the 2 or 4″NPT threads of the buoy.
a. It is highly recommended to use a strap wrench to gain an additional 1/2 to full turn on the pipe past hand tight.
b. It is recommended to attach a backup tether between the deployment pipe and buoy frame to protect the sensor/pipe assembly should a storm event cause it to loosen.
9. If deploying in brackish or saltwater environments, ensure a sacrificial anode is securely installed on both the instrument cage as well as the buoy frame. Inspect these regularly and replace as needed.
10. Ensure that the instrument cage is securely attached to the buoy frame. If any sensors are mounted to the cage, it is highly recommended to install a CB-CCA cage clamp to prevent rotation during deployment from stressing any cables. In rough water, welding the cage to the frame is advised.
11. Secure and protect all sensor cables.
a. Attach separate tethers or strain-relief cables such that the sensor communication cable and buoy connectors bear no weight.
b. It is advised to install cable armoring (one option is to slit 3/8″ ID EPDM rubber hose and secure with cable ties) where a cable contacts or could potentially wear against irregular surfaces on the buoy or mooring equipment during deployment.
Power/ Communications Check (Perform on land prior to deployment)
- With all sensors connected to the X2 or iSIC-CB, connect the 6-pin solar panel plug to the SOLAR port on the logger and verify the internal batteries are sufficiently charged.
- Wait until a prescribed sample/transmission period to ensure data is coming through as expected.
- Verify that the reported battery voltage is at least 12.0V, the minimum requirement for most telemetry units and sensors.
- Battery voltage can also be measured using a DVM as explained here.
- Make sure the solar beacon is powered on by holding the power button on the the IR remote included in the X2/iSIC-CB maintenance kit for four seconds. Additional remote command information can be viewed here.
- When placed in strong sunlight, confirm that the battery voltage for the system rises. A slight downward trend in system voltage may indicate a solar panel or solar regulator issue that will need resolved before an unattended deployment. It is important to keep all three solar panels clean during operation to ensure battery recharging is optimal.