UH LADCP Documentation


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LADCP Deployment and Recovery

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Hardware Installation (LADCP and cables)

Rosette and Hangar setup

All images on this page are thumbnails: click on the image to see a larger version.

Special notes on the BB150 are in a separate section.

Before Installing

Before installing the LADCP on the rosette, test the cables and computer you will be using. Talk to the instrument and adjust the communication and baud rates. It is important to know everything is working before you install the LADCP on the rosette.

LADCP installation

The ADCP is installed in the CTD rosette. The transducers are pointing down, and are oriented to minimize backscatter from rosette frame elements. Proper staging of the instrument. Transducers are delicate, so make sure to put a piece of stiff foam under the transducers if you set the instrument down (eg. from the LADCP box). Make sure also to put the foam back!!

  • mounting WH300, Scripps rosette:

    wh300 mounted on rosette

  • Always put foam under transducers:

    bb150 on PMEL rosette

Safe Orange Battery (SOB)

The battery that powers the ADCP during deployments is known as an “S.O.B.” (for Safe Orange Battery). It consists of an open orange plastic shell containing a flexible, oil-filled bladder, which in turn contains the elements of a normal lead-acid battery. The SOB is set into the rosette frame at the bottom, opposite the ADCP. It should reside in a basket or tray of some sort.

DO NOT put pressure on the top of the SOB, as that may deform the plastic or box or urethane bladder and cause leakage.

  • SOB in wire basket

    BB150 on Scripps rosette

  • SOB on the PMEL rosette

    SOB on PMEL rosette

  • SOB basket made of expanded metal for Scripps rosette

    Scripps rosette

UH LADCP cabling diagrams

The RS232 Y-cable layout for the WH300 or WH150 is shown below

UH WH300 cable layout

The cabling diagram for two-LADCP set-up is shown in this note.

Two ends of the Y-cable in the hangar attach directly to the instrument and to an adapter (going to the battery). The remaining end should be attached to an extenstion cable, so the day-to-day plugging and unplugging occurs on an extension, not the Y cable directly.

For either LADCP used, the extension from power+communication cable should be made accessible to the outside of the rosette. These cables will be dummied off and secured during deployment, and attached to the long pigtails that go into the wet lap during download (where the computer and power supply are).

secured t-cable dongle

The long pigtails should be secured out of the way when the package is deployed, and should be able to be bungied up, out of the way, when download and charging are underway. We do not want the cable to get in anyone’s way.

Do your best to protect the Y-cable: use extensions on it if there will be multiple plug/unplug instances. These are hard to manufacture in a reliable manner: consider them to be rare and fragile.

Laptop setup

Here is an example of the laptop setup on one cruise. The battery charger shown is the AMREL; the TDK-lambda could have been used. (The black cubical battery charger does not work with UH LADCP cables because we have a diode in the cable, and that confuses the charger. It can only be used to charge the SOB directly, i.e. not through a Y-cable or through the BB150 endcap).

wet lab layout

This picture shows the Amrel linear power supply display when it is toggled off.

power supply

Cables and connectors

7-pin rectangular plugs and connectors (WH300/WH150, RS232)

  • 7-pin plugs are delicate
  • BE CAREFUL to pull the connector not the cable
  • BE CAREFUL to brace the bulkhead connector when pushing
  • DO NOT FORCE it. If it is hard to connect the plug, add a little appropriate lubrication.
  • DO NOT BEND, DO NOT LIFT. The bulkhead connectors, especially, are vulnerable to breaking inside. Any twisting, bending, or lifting is liable to break the internal connections or perhaps weaken the seal against water.

LADCP power+communication cable

  • KEEP CLEAN AND DRY: “clean” means no lint, so dry the plugs and pins with kimwipes not paper towels. “Dry” means dry off the plugs if there are little beads of water.
  • POWER OFF FIRST: There’s alot of salt water out there.

Cables and communication

There are two models of LADCP that might be used:

Medium-sized (2’, 120lbs), BEST
  • WH150, communicating with RS232

  • “Y” cable, with ends for
    • WH150
    • laptop serial communication with WH150
    • battery
Small (1’, 40lbs), weaker
  • WH300, communicating with RS232

  • “Y” cable, with ends for
    • WH300
    • laptop serial communication with WH300
    • battery

Serial cable conventions

This document contains serial cable pin conventions and a pinout diagram for a WH300 power/communication cable. It may come in handy.

Serial notes:
  • UH LADCP ‘Y’ or ‘Star’ cables have a diode in the segment that goes to the computer. You cannot do a continuity test (or pin out) the line(s) with a diode.
  • You cannot pin out a cable that goes through an RS232-RS422 converter

Battery info

Purging gas buildup

  • For the plastic (oil-filled) battery, venting should be done when there is a noticeable buildup of gas inside the chamber. Loosen but do not remove the cap on the valve, and press on the gas bubble.
  • DO NOT let any oil get out. Someone is sampling hydrocarbons.
  • NOTE: Barely finger-tighten the nozzle, just enough for the o-ring to grab.

Power supply and charging

We have several chargers, with different ages and purposes.

  • AMREL Programmable Linear Power Supply, with these settings:
+VSET = 28.300
-VSET = 29.010
+ISET = 2.0
-ISET = 1.8
 The other 2 settings are
  • Max voltage is 57.31 V; max current is 1.8 A.
  • When charging is initiated, the battery draws the max current (1.8A). and is current limited. After some time (less than a minute when the SeaBattery was new, now about 10 minutes) the current drops and it beeps as it switches from current-limited to voltage-limited charging. It can switch back and forth a couple times between CC (constant current) and CV (constant voltage) before settling down for good. We let it charge until the current draw has dropped to 0.65 A (about 40min for a full-depth BB150 cast). If you charge much longer or allow the current draw to drop lower than this, the outgassing increases and you have to purge every cast. Toggle off the power output using the righthand on/off button (leaving the machine on but not charging). Power supply display shows “ALL OUTPUT OFF”. see picture
  • TDK-lambda Programmable Power Supply

    Settings are similar; concept is the same

  • Commercial Battery charger can only be used to charge a battery directly. Our cables have a diode in them which makes the commercial charger NOT WORK with the Y-cable or the BB150 cables.