Logging Data; Power-On Mode - Measurement Computing WebDAQ 316 User Manual

USB connectors
The two high-speed USB ports can be used for connec ons to a mass storage device and approved WiFi
adapter.
When removable media is plugged into the WebDAQ, the opera ng system opens it for wri ng. Use the FUNC
bu on or web interface to unmount the USB device before removing.
Use a self-powered hub when external media requires higher current
USB-powered hard drives may use an excessive amount of current during opera on. The WebDAQ
device could shut down or experience other errors if the power requirements of a connected device
exceed the power available. Use a self-powered hub if the current requirement of external media
exceeds 500 mA.
We recommend that you connect USB-powered hard drives before powering up the WebDAQ.

Logging data

You can log up to 3 GB of data to internal WebDAQ storage. To generate larger data files, log data to external
media with a storage capacity suitable for the acquisi on. USB drives and SD cards are available in different file
formats, and OS support for each format varies. WebDAQ supports FAT32, exFAT, ext2/3/4, NTFS file systems.
When genera ng large data files with Windows or Mac, or transferring files between opera ng systems, we
recommend using external media forma ed with the exFAT file system, such as an SDXC memory card. When
running Linux, use external media forma ed with the ex2/ex3/ex4 file system. Refer to the WebDAQ help FAQ
for more informa on about file formats.
File too large error
If you generate data that exceeds the capacity of the selected storage loca on, a "File too large" error is
returned and the acquisi on stops. To avoid interrup ons, select a storage loca on with a large capacity.
Logging data to external media
Acquiring data at high speeds can generate large file sizes. If you expect to acquire a large amount of
data to a single file when logging to external media, do not use media forma ed with the FAT32 file
system. FAT32 is limited to a 4 GB maximum file size. If the log file on FAT32 media grows beyond that
size, a "File too large" error is returned and the acquisi on stops. Before star ng a logging session of
this type, reformat the media using a different file system such as NTFS. Refer to the Frequently Asked
Ques ons help topic for more informa on about file systems.

Power-On Mode

WebDAQ Series hardware can be configured to start automa cally when power is applied, instead of requiring
users to press the POWER bu on. This is useful if the WebDAQ is opera ng in a remote loca on and a power
loss occurs. This "power-on mode" is enabled by removing a 2-pin jumper (labeled W1) from the WebDAQ
circuit board.
When jumper W1 is removed, the device does not shutdown completely unless the power adapter is
unplugged from the device or power source.
Perform the procedure below to remove jumper W1 from the WebDAQ circuit board and enable power-on
mode.
Cau on! The discharge of sta c electricity can damage some electronic components. Before removing
the WebDAQ device from its housing, ground yourself using a wrist strap or touch the computer chassis
or other grounded object to eliminate any stored sta c charge.
1. Power down the WebDAQ device and disconnect the power supply.
WebDAQ 316 User's Guide
page 16