Frequently Asked Questions
Help! I can't communicate with my 2D-ACM.
If the instrument has been programmed to operate in "interval"
mode, the instrument may be in a low-power "sleep" state between
intervals. The communications issue may be solved by cycling the
kick-start switch several times before trying to communicate. If this
still does not work, the power to the instrument will need to be turned
off and back on again. This means opening the unit and disconnecting and
re-connecting the battery if installed, even if the instrument is
currently being powered by the test cable power supply.
When I unload the data from my 2D-ACM, the data is scrambled.
The scrambled data file may be caused by a conflict between the
current configuration in the instrument and the configuration in ACMPro.
If you have an instrument connected to your computer, and the
configuration in ACMPro does not reflect how the attached instrument was
originally programmed, the offloaded data may be unreadable. For
example: if you offload a 2D-ACM with a CTD installed using ACMPro, and
then, when completed, disconnect this 2D-ACM from the computer and
connect a second 2D-ACM with a different configuration (for example,
without a CTD) and do not perform the CHECK INSTRUMENT routine before
offloading the memory, ACMPro will try to use the previous configuration
as a format for this data offload, and the data will be unreadable.
Using the terminal routine shown in the video on the FTP site will avoid
this problem. Also, open a new session of ACMPro and CHECK INSTRUMENT
every time an instrument is connected to the computer.
I have tried to update the time and date in my 2D-ACM, but the system won't store the new time/date. What is the matter?
2D-ACM time and date are stored in volatile memory powered by a
coin-cell battery. If the coin-cell is bad, it is possible that the
instrument will lose its constants, or will not save the time and date
and so will not work in delayed start or interval mode.
A good way to test this is set the time and date in the instrument,
either through ACMPro or in a terminal program using the TIME and DATE
commands and then cycling power to the 2D-ACM (if a main internal
battery is installed be sure to cycle to disconnect/reconnect this to
cycle power to the CPU. Now check the time and date in the 2D-ACM. If
they are still correct, the coin-cell battery is OK. Contact FSI about
how to replace the coin-cell battery.
My 2D-ACM accepts a time and date, but there are no system constants.
The constants can be reloaded from the CD-ROM that was supplied
with the unit. Or contact FSI for the most recent list of constants (we
will need to know the unit serial number).
Do you have a Quick Start guide for the 2D-ACM?.
We recommend the following videos to help get you started with
deploying and configuring your 2D-ACM Current Meter. These videos can be
found on Youtube at the following link:http://www.youtube.com/user/HermanFSI#p/u
How
deep can I deploy my FSI Wave Meter?
FSI Wave Meters use the PUV method of measurement, meaning that wave
height and direction are calculated from pressure and horizontal velocity
measurements. The depth of deployment is related to the period of the
waves being measured. Following is a chart showing the minimum wave period
that can be accurately measured at the corresponding depth.
| Deployment
Depth (M) |
Min.
Wave Period (Sec.) |
| 20 |
4.4 |
| 18 |
4.2 |
| 16 |
4.0 |
| 14 |
3.7 |
| 12 |
3.4 |
| 10 |
2.8 |
| 6 |
2.4 |
| 4 |
1.9 |
| 2 |
1.1 |
See the
application note on Wave
Post Processing for more information on how the FSI 3D Wave meter
measures wave direction and height. Other considerations in mounting the
wave meter are:
The
maximum depth correction possible with an RPT-based (Resonant Silicon
Pressure Transducer) wave meter is 31.63 meters; the 3D-WAVE meter will not
provide accurate directional wave data if installed below this depth.
How
can I determine the expected battery/memory life of my current meter?
FSI supplies a BatLife software program that calculates these parameters
for a given configuration. Please contact FSI for more information.
If
my 2D-ACM data provides a current direction of 180.121 and speed of
10.034, what exactly does this mean?
Current direction (unlike wind) is measured in the direction to which it
is flowing. In this case, the current is 10 cm/sec, and it is flowing to
the South.
Does
my current meter require calibration? If so, how often?
The initial current meter calibration comprises three aspects - tilt,
compass, and velocity. FSI recommends that all three parameters be
recalibrated after one year of use.
I
want to add a Turbidity/Fluorometer/Oxygen sensor to my current meter. Can
this option be retrofitted?
2D-ACM and 3D-ACM current meters include A/D inputs which accept signals
from external sensors with 0-5V output. Integration of these sensors can
typically be accomplished by adding a connector and internal wiring
changes. For more information please contact FSI.
What does "Timeout Error, no data received" mean?
Certain laptop computer users may experience errors during the high speed Memory Retrieval.
The error message that occurs is called "Timeout Error, no data received". Normally this problem occurs when other programs are running during Memory Retrieval. Most laptop computers run power management or battery monitoring drivers that reduce the CPU time available to receive high-speed serial data. Downloading data from an instrument at high data rates requires almost all the CPU time. Interrupt latencies caused by other drivers can cause the receive buffer in the 16550 UART to overflow. When this occurs, data is lost, causing a timeout error in the retrieval process.
To avoid this error, close or disable all applications before running the Memory Retrieval. If you still experience problems during the Memory Retrieval you may have to disable the Power Management option in the PC BIOS. To determine how to change your PC BIOS consult your PC Manual. If you still cannot resolve this problem please contact FSI.
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