My Graph function in the SensDesk portal – Compare your readings

Plotting the values of one quantity in a simple graph is a standard feature of any monitoring software, including PDMS, Nagios, PRTG or SensDesk. It is even included in some devices, such as HWg-PWR (although it tends to be limited in such cases). Graphs provide a quick overview and analysis of the measured data. They make it easy to spot rising or falling trends or periodic events. Some software systems can plot the readings from several sensors in one graph, as long as the measured physical quantity is the same. However, few applications can plot different quantities with different scales in a single graph because such an ability is computationally and graphically demanding.

Typical applications of My Graph

The My Graph function is used to compare multiple measured values in order to spot any dependencies. This is useful for analyzing the causes of alarm situations as well as for optimizing the operation of equipment such as HVAC.

Checking the temperature in refrigerators, freezers and cooling boxes

It is important to monitor temperatures in refrigerated areas where doors are frequently open or closed. By looking at temperatures and other sensors in time, it is possible to detect faulty refrigeration equipment; for example, causes of rising temperature can be identified by correlating temperatures with door contacts. If the temperature only rises when someone enters the cooler, there is no reason for concern. The graphs can be also used to generate reports with temperature values plotted in time in order to demonstrate compliance with storage requirements, e.g. for food, pharmaceuticals or other critical substances. For monitoring temperature and humidity, devices such as STE2 or Poseidon2 3266 can be used.

With a HWg-PWR25 device, energy consumption metering can be added to the system. By comparing the temperature in the refrigerated area with the energy consumption, it is possible to detect frost buildup or coolant leaks (rising electricity consumption without a change in temperature is an indication of an imbalance in the system and rising costs).

Monitoring the environment and hot and cold aisles in server rooms

Environment monitoring frequently involves checking the temperature in racks or data centers. For administrators, this information is absolutely essential, even though they may hesitate to store this data in a third-party portal. This information allows to correlate temperatures in a rack with doors being opened and closed, or to compare temperature trends in a cold aisle in a data center with door contacts, air flow and humidity; this can help identify problems with air circulation, such as mechanical obstructions caused by users or A/C technical problems. As a result, it is possible to reduce datacenter operating costs and increase reliability for customers. In datacenters, frequently used devices include Poseidon2 4002 and Poseidon2 3268.

Energy consumption monitoring in office spaces

In office spaces, environment monitoring is usually a complete solution that, in addition to electricity consumption and temperature, also monitors parameters such as lighting intensity and air quality. Even though these parameters may fall into the Measurement & Control domain, independent monitoring has its place in energy management and in ensuring correct function in order to maintain productivity and efficiency. When blinds in a building are raised on a hot sunny day, A/C operation may become very expensive. Vice versa, when blinds are shut outside of the heat peaks, artificial lighting is used unnecessarily and, if coupled with lower air quality, reduces staff productivity. For these applications, Poseidon2 3468 and HWg-PWR12 are frequently used. These devices can be installed on DIN rails in electrical cabinets.

Temperature and humidity monitoring in greenhouses

When growing plants in closed greenhouses, air circulation needs to be ensured in order to maintain a homogeneous environment. By monitoring temperature and humidity at several places at the same time, crop yield and quality can be improved. Suitable devices include Poseidon2 4002 or Ares 12 that can, for instance, control multi-point air circulation together with automated watering.
 

Monitoring environment stability and producing heatmaps in warehouses

In many cases, it is necessary to monitor whether the environment in the given premises is stable, i.e. without significant fluctuations. This monitoring may be important to preserve the stored goods (food, flowers etc.), as well as for diagnostic purposes. Temperature or humidity sensors must be placed at the important locations, but also away from sources of false alarms, such as due to draught. With the My Graph function, it is easy to show the differences of the respective values and to list details.
 

For more information about the graph functions and their use, see a separate Application note or the video below.