The SG-Link®-OEM -LS is a miniature, wireless, low-power, two-channel analog input sensor node ready for OEM integration.
Product Highlights
- One differential and one single-ended analog input channel and an internal temperature sensor
- Ideal for short-range wireless measurement of many Wheatstone bridge and analog-type sensors including: strain, force, torque, pressure, acceleration, vibration, magnetic field, displacement and geophones
- Supports continuous, burst, and event-triggered sampling and datalogging to internal memory
- User-programmable sample rates up to 4096 Hz
- Comprehensive SDK and OEM form factor for rapid integration
- Smaller size and lower power consumption than the SG-Link-LXRS and SG-Link-OEM-LXRS
Wireless Simplicity, Hardwired Reliability™
High Performance
- Node-to-node synchronization up to ±32 microseconds
- Lossless data throughput under most operating conditions
Ease of Use
- Rapid deployment with wireless framework
- Optional web-based SensorCloud™ interface optimizes data storage, viewing, and analysis.
Cost Effective
- Out-of-the box wireless sensing solution reduces development and deployment time.
- Volume discounts
General |
|
---|---|
Sensor input channels |
Differential analog, 1 channel Single-ended analog, 1 channel |
Integrated sensors |
Internal temperature, 1 channel |
Data storage capacity |
2 M bytes (up to 1,000,000 data points, data type dependent) |
Analog Input Channels |
|
Measurement range |
Differential: full-bridge, ≥ 350 Ω (factory configurable) Single-ended: 0 to 3 V dc |
Accuracy |
± 0.1% full scale typical |
Resolution |
12 bit |
Anti-aliasing filter bandwidth |
Single-pole Butterworth -3 dB cutoff @ 250 Hz (factory configurable) |
Bridge excitation voltage |
+3 V dc, 50 mA total for all channels (pulsed @ sample rates ≤ 16 Hz to conserve power) |
Measurement gain and offset |
User-selectable in software on differential channels gain values from 104 to 2560 |
Integrated Temperature Channel |
|
Measurement range |
-40 °C to 85 °C |
Accuracy |
± 2 °C (at 25 °C) typical |
Resolution |
12 bit |
Sampling |
|
Sampling modes |
Synchronized, low duty cycle, datalogging |
Sampling rates |
Continuous sampling: 1 sample/hour to 512 Hz Periodic burst sampling: 32 Hz to 4096 Hz Datalogging: 32 Hz to 4096 Hz |
Sample rate stability |
± 3 ppm |
Network capacity |
Up to 2000 nodes per RF channel (and per gateway) depending on the number of active channels and sampling settings. Refer to the system bandwidth calculator: http://www.microstrain.com/configure-your-system |
Synchronization between nodes |
± 32 μsec |
Operating Parameters |
|
Radio frequency (RF) transceiver carrier |
2.405 to 2.470 GHz direct sequence spread spectrum over 14 channels, license free worldwide, radiated power 0 dBm (1 mW) |
Range for bi-directional RF link |
70 m line of sight |
RF communication protocol |
IEEE 802.15.4 |
Power source |
External: +3.2 to +9.0 V dc (9 V dc alkaline battery provided) |
Power consumption |
See power profile : http://files.microstrain.com/SG-Link-OEM- LS-Power-Profile.pdf |
Operating temperature |
-40 ˚C to + 85 ˚C (excluding 9 V battery) |
Acceleration limit |
500 g standard (high g option available) |
Physical Specifications |
|
Dimensions |
33 mm x 30 mm x 7 mm |
Weight |
8 grams |
Integration |
|
Compatible gateways |
All WSDA® base stations and gateways |
Compatible sensors |
Bridge type analog sensors, 0 to 3 V dc analog sensors |
Connectors |
Solder pads or screw terminal connector |
Shunt calibration |
Internal shunt calibration resistor 499 KΩ, differential channel |
Software |
SensorCloud™, Node Commander®, Windows XP/Vista/7 |
Software development kit (SDK) |
Data communications protocol available with EEPROM maps and sample code (OS and computing platform independent) http://www.microstrain.com/software-development-kits-sdks |
Regulatory compliance |
FCC (U.S.), IC (Canada), ROHS |
What is Multipath?
Multipath is the phenomenon whereby a radio signal arrives at a receiver’s antenna by more than one path. This occurs by the reflection, diffraction, or scattering of radio waves from atmospheric ducting, reflection from water bodies or terrestrial objects (like mountains), etc.
Does Multipath impact signal strength?
Yes, multipath propagation of radio signals causes fading of the transmitted signal, which can be indicated by fluctuations in signal strength when received by the signal receiver.
How do I mitigate Multipath?
Pe-position base station or node to mitigate possible multipath interference.
Ensure a clear path to the antenna for the strongest signal, enhancing the strength of the strongest signal AND reducing the strength of the weaker signals.
Learn More: Mutipath Propagation
The WSDA-RGD (with internal GX3 inertial sensor) is configured to produce the following messages on startup.
GPS Data (1 Hz):
- UTC Time
- LLH Position
- NED Velocity
AHRS Data (100 Hz):
- Euler Angles
From this output the WSDA logs:
GPS (1 Hz):
- latitude
- longitude
- height above ellipsoid
- height above MSL
- horizontal accuracy
- vertical accuracy
- speed
AHRS (100 Hz):
- roll
- pitch
- yaw
The WSDA-RGD does not log any data until it gets a valid time, if it is set to get time from GPS only it will not log any output from the GX3 until the UTC timestamp from the GX3 is valid, even though the GX3 is producing valid AHRS data.
This data is not user configurable and is not available as a live stream through LiveConnect.
All LORD MicroStrain wireless sensor nodes, wireless base stations, and wireless sensor data aggregators are shipped from the factory with their radio frequency set to channel 15 (2.425 GHz).
This channel setting was established during 2012.
Previously all wireless products were set to channel 25 (2.475 GHz).
If you are mixing new nodes and base stations with older nodes and base stations, please be cognizant of these different channel settings.
The Node Discovery function of Node Commander will help you sort out which nodes are on what channels; Node Discovery is channel independent and allows the base station to communicate with any node, no matter what channel it is on
Sampling methods such as synchronized sampling, low duty cycle, network broadcast, etc. require that all nodes are on the same frequency so you will want to insure that you have adjusted the channels settings of the nodes to suit.
The wireless nodes all have 2 Mbytes of datalogging memory. This 2 Mbytes is organized into 8,191 ‘pages’ of memory, each page holds 132 data points. The maximum number of data points that can be held in memory can be calculated as follows: 8,191 pages x 132 data points/page = 1,081,212 total data points.
Now the question arises, ‘how long can a node datalog before its memory is full?’. The answer is that it varies depending on how many channels are being sampled and what sampling rate has been set. Here are two examples:
Let’s set a V-Link-LXRS so that channel 1 is active with a datalogging sampling rate of 2048 samples per second and we launch continuous datalogging. Our calculation would be:
- 1 channel x 2,048 samples per second = 2,048 data points per second
- 1,081,212 data points / 2,048 data points per second = 527 seconds
- 527 seconds / 60 seconds per minute = ~9 minutes to fill the memory
Let’s set a G-Link-LXRS so that channels 1, 2 and 3 are active with a datalogging sampling rate of 32 samples per second and we launch continuous datalogging. Our calculation would be:
- 3 channels x 32 samples per second = 96 data points per second
- 1,081,212 data points / 96 data points per second = 11,262 seconds
- 11,262 seconds / 60 seconds per minute = ~187 minutes to fill the memory
White papers are posted on: This page
In FINITE sampling, the user sets a total number of samples to be taken which equates to a time period. Because the sampling rate per second is known, the user can adjust the number of samples to be taken to determine how long the sampling period will be.
In CONTINUOUS sampling, the user does not set the total number of samples and therefore does not set the time of the sampling period. By selecting CONTINUOUS sampling, the user is instructing the system to sample data until the user manually stops the sampling (via software), the power is cycled, the on-board datalogging memory is full, the battery dies, the power fails, etc.
LORD MicroStrain® Wireless Sensor Networks provide several data acquisition modes including:
- Synchronized Sampling
- Armed Datalogging
- Streaming
- Duty Cycle
See the particular wireless node for specifics.