of Things starts with a Sensor
flash flood warning for swift protection against hazards
IoT is already a widely known and to some extent controversial
term. Yet, the Internet of Things is all around us every day,
whether we realise it or not. If, for example, you can control
TV recordings or your lights at home using your smartphone, this
falls under the category of the "smart home".
If a company uses automatic, independent processes in its organisational
measures, we call this a "smart factory" or "Industry
4.0". Other related terms include "smart energy",
"smart mobility" and "smart health". No matter
the sector, the sensor is ultimately the most important supplier
of data and thus the key component of the IoT process. When fitted
to an object, different sensors can be connected to local and
global communication networks. The final step in the process
is to analyse the data on networked computers or in a cloud.
IoT processes are highly customised and are undergoing continuous
development. KELLER has already worked with international companies
to develop numerous "smart", customer-specific total
solutions in various sectors and applications. The following
five examples illustrate how KELLER sensors fuel IoT progress:
Flash floods are sudden and unpredictable. Within minutes, floods
can rise over the banks of streams and onto the roads, sweeping
away cars, devastating houses, and killing people.
Although weather services usually issue warnings before severe
weather hits, many towns are poorly - prepared for flash flooding.
This is hard to believe, since most regions have detailed special
maps that deliberately highlight the danger zones so that the
places at risk can prepare accordingly. However, these maps are
rarely to be found in town halls, fire stations or the emergency
services, which is why people largely fail to take proactive
measures. Moreover, the special maps are relatively roughly drawn;
obstructive buildings and roads acting as channels are not always
shown. So, while the maps may identify a problem, they provide
no viable solution.
Which is why an loT solution is capable of identifying dangers
early and reliably raise the alarm for imminent flooding is essential.
This means emergency services can be notified automatically,
in a matter of seconds, so the appropriate measures can be taken
promptly, even in the most remote corners of the region.
KELLER's GSM-2 remote transmitter forms part of warning systems
like these. The GSM-2 is a combination of an autonomous data
logger and a remote transmitter in one device. When combined
with a pressure transmitter or a level sensor, it reliably transmits
water levels and pressure data via the GSM mobile phone network
by SMS, e-mail or FTP to those responsible in order to issue
flood warnings before tragedy strikes.
The US National Weather Service(NWS), for example uses GSM-2
solution with accurate level sensors (1), a remote transmitter
(2) and a special type of software (3) adapted to its needs.
KELLER also provides technical support for setting up, installing
programming the system, which sends the responsible workers an
SMS notification when the levels rise. After the system has been
implemented, the infrastruc:ure can be converted from manually
positioned mobile barriers to permanently installed swing gates
that close when flash flooding occurs.
beer tanks delight both landlords and breweries
A level measurement with a remote transmitter is not just highly
practical for detecting hazards but also for other level and
fill level applications. Take pubs, for instance, where an emptying
beer tank could be equally dangerous.
In this application, two pressure sensors work at the heart of
the solution to measure the level of liquid in the tank and to
send a warning message to the brewery by e-mail via the GSM-2
remote transmitter, the mobile phone network, and the Internet.
The brewery sends an automatic order proposal to the landlord,
who simply has to confirm the order.
This automated, "smart" M2M (machine-to-machine) solution
reduces stress for landlords and saves brewery drivers from profitless
emergency weekend deliveries. Inaccurate order entries are now
a thing of the past, shipping can be optimised and landlords
have a continuous supply of fresh beer. Crisis averted.
'Smart' fuel tank management with fuel proces updated daily
and drinks, fuels are another liquid ideally suitec to being
managed by means of automated, "smart" processes. The
remote monitoring of fuel levels in heating oil, diesel, and
petrol tanks is a great support to mineral oil companies, petrol
station owners, and property managers alike.
KELLER developed the "EasyOil1" remote monitoring system
in partnership with a Swiss mineral oil supplier. This system
has reall found its place in the market and is the key selling
point for customers in 80% of the contracts concluded for heating
The order process is the same as for the beer tank: The pressure
and level of oil are measured at the lowest point in the tank,
the current content in litres is calculated according to the
shape of the tank and the data is transmitted via GSM. A special
feature of this application is the customer-specific software.
In addition to the current data such as fill level, consumption
and order history, it also contains oil prices, which are updated
twice a day. This combined information optimises the order process,
allowing customers to stockpile when the price of oil is low
or the tanker is close by.
Because there is a risk at petrol stations that an electric spark
could cause the gaseous atmosphere to explode, any pressure transmitter
taking measurements in this type of environment must be intrinsically
safe. For this application, the GSM-3 remote transmitter has
been extended to include a box with built-in safety barriers
that limit the electric output of the measurement system within
the zone at risk of explosion (the ex zone), thus preventing
Comprehensive monitoring of chemical distribution
The risk of explosion is also a key issue when it comes to chemicals.
Warehouses belonging to chemical manufacturers and distributors
contain numerous different chemical containers holding all manner
of different explosive and harmful contents.
More often than not, the fill level inside chemical containers
is neither measured nor displayed visually on the outside. One
option would be to install a highly resistant float gauge but
this is not sufficient to guarantee safe transport or to monitor
the contents of the tank continuously during transport. Yet continuous
monitoring is an essential factor in guaranteeing a delivery
in line with the relevant standards.
If the pressure
within the container is measured as well as the fill level, it
is possible to check whether the container is properly sealed
or whether it was opened during transport. The log also indicates
whether or not the container was subjected to excessive accelerations.
In this application, the fill level is also measured by two compact
pressure transducers, the series 7LD. KELLER has developed a
solution that integrates the transducers while keeping-the container
in its original condition. Since the container is under pressure,
one transducer is affixed at the top of the container to measure
the ullage pressure, and the other transducer affixed at the
bottom to measure total container pressure. The differential
pressure between the two 7LD transducers is equal to the chemical
level within the container.
This information, along with temperature and container location,
is transmitted, connecting to the Internet of Things that facilitates
access to vital information where it is needed most to ensure
proper chemical monitoring.
monitoring the bridge loads
Another area in which sensors facilitate smart monitoring is
in power measurement, where pressure sensors are employed to
measure and record load distribution on bridges.
The volume of traffic on our roads is an unknown quantity and
the growing proportion of lorries (or trucks) places increasing
loads on bridges. But the ground is not a static feature either,
since plate tectonics cause everything on the planet to move
and the ground beneath our feet to change on a daily basis. These
two variables will cause the load distribution on a bridge to
change. To ensure continuing safety, it is necessary to continuously
monitor and identify changes in the load distribution using sensors.
Previously, bridge loads were displayed using a mechanical indicator
on the bridge bearings, which had to be read on site. KELLER
has focused its attention on this central supporting element
of the bridge and integrated a networked pressure measurement
solution into the bearing. The bridge transfers the loads to
an elastomer cushion (1). Between the pressure sensor (2) and
the elastomer is a layer of grease (3) that functions as a pressure
transfer medium and makes it possible to measure the internal
pressure due to loading. This change in pressure is determined
by a pressure transmitter whose customer-specific design integrates
perfectly into the bridge bearing.
The GSM module (4) reads the data directly via a digital interface
and sends a warning message to those responsible depending on
the measured value. The use of stainless-steel-covered pressure
sensors with an especially long service life guarantees decades
of reliable measurements and functional safety. With the Internet
of Things, bridges can be reliably and continuously monitored
for changes in load distribution that pose a threat and closed
off if necessary.
The Internet of Things offers "smart" solutions that
help make life easier and more convenient, improve and streamline
processes, and receive information in good time that was previously
unavailable or difficult to acquire. Smart solutions are highly
personalised but always begin with an object and a sensor.
We would be happy to advise you on your own customised IoT requirements
is a member of the LoRa Alliance
The long range wide area network "LoRaTM" connects
objects via radio and offers safe, bidirectional communication
within the Internet of Things. LoRaWAN is based on the open industry
standard LoRa and has been set out by the non-profit organisation
LoRa Alliance, of which KELLER AG fur Druckmesstechnik is a member.
This technology offers high coverage and a low level of energy
consumption, which is especially suited to battery-operated applications.
For more information,
+44(0) 845 643 2855 Fax: +44(0) 845 643 2866