With so many systems to choose from, choosing the right wireless remote sensor based monitoring system can be confusing and a complex decision.
At Dyna-mo Instruments we take an agnostic approach to system adoption, focussing on the right system for the right application taking into consideration ease of use, wireless range, data management, data storage, cost and data visualisation platforms.
Installation of a wireless remote monitoring system requires 3 key components.
Communication | Devices | Power |
Providers of systems have approached these 3 key components in a variety of ways, each with its own considerations.
Communication
Collecting data from remote wireless devices can be achieved in 2 ways.
Direct data transmission from sensor to server
Local data transmission from sensor to local gateway, then gateways communicate data to a server.
The majority of wireless sensor systems have opted for the first of these methods, sending data from sensors to a local gateway, which in turn then sends the data over LTE mobile signal to a physical or cloud server.
The communication from sensor to gateway can be achieved using one of several protocols.
2.4 or 5Ghz Wi-Fi
LoRa or LoraWAN
Bluetooth
There are several proprietary communication protocols promoted but in principle these rely on one of these methods as a foundation.
Considerations
Ultimately the choice of communication protocol is a balance between communication range, data rate and power consumption.
The more data that needs to be communicated the faster data rate required, therefore the shorter the communication range and higher the power consumption. Unless you can facilitate very short communication distances in which case Bluetooth provides a balance of higher data rate and low power consumption.
Direct Communication | Mesh Connection |
Many systems resolve the shorter range communication by implementing relay devices or a mesh network between devices.
The risk with mesh connections is that dependent on the installation a single device can become a key gateway to data reaching the gateway, and should this device fail or run out of power then the entire mesh beyond this device will lose connection. This can be mitigated by ensuring that the installation layout takes this into consideration, and ensures that there are no singular devices that are critical to the mesh communications integrity.
Devices
Most wireless monitoring systems have proprietary remote battery operated sensors as part of their offering. In addition to these they have wireless sensor nodes that enable the integration of cabled geotechnical, environmental and structural sensors. These nodes allow for the connection of several sensor output types.
4-20mA
0-5 / 0-10V
Vibrating Wire
Digital
Connecting third party cabled sensors vastly expands the potential applications for wireless monitoring systems. Connecting analogue sensors is usually a relatively straight forward process. However, there is a requirement to correctly converting the data readings to a meaningful output. This process has 3 key factors.
The base reading the sensor is able to provide
The range from base to maximum reading the device is able to provide
The sensors unit of measure (UoM).
To find our more about the difference between some of the leading providers systems, click on this link
Considerations
Various system providers offer very similar systems from a top level view. But as often is the case the devil is in the detail.
Some of the key considerations are data visualisation, configurability, subscription costs, ease of use, device cost, battery life and support.
Power
Power considerations come in 3 parts for wireless monitoring system.
Gateway power supply
Proprietary device battery life
3rd party sensor power supply
Gateway power supply and proprietary device battery life is compared in the table below. When it comes to 3rd party sensors, the consideration can be complex. There are two groups of sensors that determines how power supply needs to be configured.
Static sensor readings of the current state
Dynamic data readings (average over time / min or max reading)
3rd party sensors that provide dynamic data readings require continuous power supply. If this power supply is drawn from a connected communication node, this significantly reduces the battery life and is more often than not, an ineffective method of powering 3rd party sensors. In addition many sensors required 24Vdc power which is impractical to power from an analogue node. Therefore a separate power supply is necessary. This can be in the form of mains or off-grid supply. In comparison static readings sensors that require 12Vdc or less can be powered directly from an analogue node*. Analogue nodes take periodic sensor readings anywhere from every 2 minutes to once every 24 hours. Each reading, the analogue nodes provides power to the 3rd party sensor, takes a sensor reading and then cuts off the power supply to the 3rd party sensor.
Considerations
Powering an onsite gateway will either require mains power conversion from 110-240Vdc or an off-grid power system will be required. We have a range of solar power systems can that provide continuous power to all of these gateways.
To support 3rd party sensors that require continuous power in order to deliver dynamic data, we have a range of low power off-grid systems to supply 12-24Vdc power.
Our services include provide training, guidance, complete system proposal and pre-configured/pre-connected system supply.
To book a training session, request a system proposal or a quotation please get in touch.
01604 832916
MONITOR | POWER | CONNECT
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