The basic model belonging to the Sonel MPI series family of multifunction meters is the Sonel MPI-535. This device combines advanced technology, measurement versatility and ease of use, offering high quality at an affordable price.

Modern platform

The Sonel MPI-535 meter is based on the same hardware and software platform as the flagship Sonel MPI-540-PV. The device is designed for safety measurements of electrical installations in residential and industrial buildings.

Comfort of work thanks to the colour screen

Like the aforementioned flagship model, the Sonel MPI-535 also features a 7″ colour LCD touchscreen with a resolution of 800×480 pixels. This guarantees comfortable handling and easy reading of parameters and measurement results. More information, the appropriate size of the displayed symbols (thanks to the large screen) and an intuitive interface make the meter easy and comfortable to use.

Image 1. Measurements with the Sonel MPI-535 meter

Measuring capabilities of the Sonel MPI-535

The Sonel MPI-535 meter enables all tests of electrical installations to be carried out in accordance with current regulations, including:

• short-circuit loop impedance measurement (also in circuits with RCDs),
• checking the parameters of RCDs,
• measurement of voltage drop,
• insulation resistance measurement,
• measurement of earth resistance (four methods),
• measurement of small resistances,
• continuity measurement of protective connections and equipotential bonding with 200 mA,
• phase sequence test,
• motor direction test,
• measurement of soil resistivity,
• illuminance measurement (after purchasing an additional lux meter probe).

Figure 1. Sonel MPI-535 – measurement selection screen

Additional features of the Sonel MPI-535

Measurement functions alone are not all that determines the superiority of advanced instruments over older and simpler designs. Thanks to the fact that the Sonel MPI-535 meter is designed on a state-of-the-art measurement platform, it has many other features that improve the work of the measurer.

Built-in self-tests allow measurements to be taken in any sequence. The manufacturer has implemented several of its procedures and has also enabled users to create their own sequences.

The factory-built procedures are not only those dedicated to measurements in low-voltage installations, but also for testing electric vehicle charging stations. The Sonel MPI-535 is characterised by high accuracy measurements, the results of which the instrument itself is able to evaluate in terms of the criteria it meets in an instant, during the test.

These criteria, depending on the test being performed, can be entered by the user or sewn into the instrument. This is the case with the protection base located in the meter, which is necessary to evaluate the result of the short-circuit loop impedance measurement. As with self-testing, here too the user can extend it with their own security features.

The built-in help screens with measurement diagrams can prove invaluable – especially for measurers with less experience. This makes it easy and easy to check how to connect a given system depending on the type of measurement being performed.

Image 2. Sonel MPI-535 short circuit loop measurement screen

Record of results and test protocol

The instrument has the advantage of a multitude of communication interfaces and cooperation with external software. Via the USB port, a removable SD memory card or via wireless communication (Bluetooth, Wi-Fi), measurement data can be transferred to a computer. Saving downloaded resources to the simplest formats and printing is provided by the free software, Sonel Reader. Use the Sonel Reports Plus software to prepare a professional test protocol.

The measurement result memory of the Sonel MPI-535 has a tree structure. In this way, the object under study can be better mapped by appropriately assigning the results to measurement points at the appropriate locations. Such a structure can be created during the test or prepared in advance in the Sonel Reports Plus software and uploaded to the meter before the measurements. Their results or a simplified PDF report can also be sent by email directly from the meter while connected to a Wi-Fi network with internet access.

Highest safety standards

Sonel pays particular attention to the safe use of its products. The designers have therefore ensured that the instrument meets the IEC-61557 standard for meter manufacturers, as well as the stringent safety standard, IEC 61010. The instrument is characterised by a CAT III 500 V / CAT III 300 V measurement category and an IP 51 degree of protection against external conditions. Each meter produced receives an individual calibration certificate, confirming that the meter maintains metrological parameters within the framework set by the factory standard.

Extensive equipment and expansion options

Standard equipment for the Sonel MPI-535 includes test leads, blade probes, crocodile clips, earth measurement kit, meter case, power supply or memory card.

If the user needs to improve his or her work, a range of additional accessories is also available. Examples include longer cables, a lux meter probe, hard clamps for measuring earthing, the Sonel AutoISO-1000C adapter for automatic measurement of insulation resistance of multi-core circuits, or the Sonel EVSE-01 adapter for measuring electric vehicle charging stations. A full list of standard and optional accessories can be found on the product page.

Image 3. Sonel MPI-535 with standard accessories

Summary

The Sonel MPI-535 meter is a modern, multifunctional instrument designed for electricians, measurers and electrical installers carrying out safety measurements in consumer low-voltage installations. The device stands out for its excellent value for money and its wide range of measurement functions, complemented by solutions that further enhance workflow, such as built-in security databases, help screens or measurement sequences. Compatibility with numerous accessories that extend the capabilities of the meter is also an important advantage. An example is the Sonel MPI-535 kit with Sonel EVSE-01 adapter, ideal for those taking measurements of AC electric vehicle charging stations.

Image 4. Measurement of AC electric vehicle charging stations using Sonel MPI-535 kit and Sonel EVSE-01 adapter

Figure 2. Sonel MPI family – comparison of premium models

Author:

Tomasz Gorzelańczyk, Sonel S.A.