MONITORING STATION INSTRUMENTATION AND MEASUREMENTS - Wind Resource Assessment: A Practical Guide to Developing a Wind Project - page 51

Table 4-6. Data storage devices

Storage device Description Download method/needs

Memory card Independent memory chips in

numerous formats (e.g., MMC,
SD, microSD, SDHC, Memory
Stick, USB flash drive) used in
cameras and other devices

Read and erased on-site or
replaced. Reading device and
software required

Solid-state module Integrated electronic device that

directly interfaces with the data
logger

Read and erased on-site or
replaced. Reading device and
software required

Data card Programmable read-write device

that plugs into a special data
logger socket

Read and erased on-site or
replaced. Reading device and
software required

EEPROM data chip An integrated circuit chip
incorporating an electrically
erasable and programmable
read-only memory device

EEPROM reading device and
software required

Magnetic media Familiar floppy disk or magnetic

tape (i.e., cassette)

Software required to read data
from the media

Portable computer Laptop or notebook type

computer

Special cabling, interface device,
and/or software may be
required

4.6.1 Manual Data Transfer
Manual retrieval requires visiting the site to transfer data. Typically this involves two
steps:

1. The current storage device (e.g., data card) is removed and replaced and sent to
another location for download. Alternatively, the data can be transferred at the
site to a laptop computer. Many loggers use an RS-232 serial port to interface
with a computer. Computers that do not have an RS-232 port can use a USB
port and USB/RS-232 adapter.
2. The collected data are transferred to a central computer where the data are
analyzed and backed up.

The main disadvantage of manual data transfer is the need for frequent site visits to
ensure that all the equipment is operating correctly. If a sensor or logger malfunctions
between visits, data that would have been collected from that point forward until the
next visit may be lost. In addition, there is an increased risk of data mishandling (e.g.,
lost or damaged storage cards). For these reasons, most wind monitoring campaigns
these days rely on remote data transfer.