BALTO Series


Test Equipment for Circuit Breakers and Protection Relays

STEVO Electric started in 2003 with the development of test equipment for DC high-speed circuit breakers (DC-HSCB). The product line was called BALTO and has gained worldwide market acceptance in the railway industry.

Currently, BALTO is the leading test unit for DC-HSCB with references in North and South America, Europe, China, Southeast-Asia and Africa. Today’s BALTO series uses batteries and ultra capacitors to store energy. The power units contain sophisticated electronics and act as current sources. They draw the energy from the batteries and ultra capacitors and inject a high current into the DC-HSCB. This type of test equipment is often referred to as primary injection test equipment. Up to 40,000A of DC current can be generated to test the DC-HSCB.

In 2016, STEVO Electric launched its BALTO CONTROLLER, a test unit for protection relays. This type of equipment is referred to as secondary injection test equipment. The BALTO CONTROLLER can be used as a stand-alone unit for testing protection relays as well as in conjunction with the BALTO Modular for testing DC-HSCB.

In 2020, Megger acquired the BALTO product range. For BALTO purchasing options please contact or your local Megger representative.

Primary injection test equipment

The BALTO Modular system, which exists in 3,000-30,000A and 4,000-40,000A versions, can generate up to 15,000A/20,000A on a single trolley, and up to 30,000A/40,000A with two trolleys in a master-slave configuration.

The BALTO Modular consists of a trolley equipped with batteries and ultra capacitors, a maximum of five power modules per trolley, and a BALTO CONTROLLER which also supports secondary injection capabilities for testing protection relays. This transportable unit was developed mainly for use in substations.

A compact version of the BALTO Modular is also available. The BALTO Compact contains only a single power unit. It can generate currents up to 3,000A or 4,000A.

The compact version can optionally be equipped with hardware and software to perform secondary injections for the testing of protection relays.

The BALTO Compact series is very easy to handle and was developed for applications in rolling stock.

Features of the BALTO series

BALTO products comply with EN 50123-2 and IEC 61992-2 standards (slope of 200 A/sec during 5 sec for accurate measurement of Ids current).

They come with a user-friendly, industry-grade touchscreen control unit, which provides accurate graphical representations of the test results. All results are stored into memory for retrieval at a later time.

All models provide auto-diagnostics and auto-calibration functions. An RJ45 and USB connector is available for retrieval of test results.

Standard tests of the BALTO series

The BALTO primary injection test set can measure the Ids, di/dt, opening time and voltage drop / resistance of DC high-speed circuit breakers. It can also be used to calibrate auxiliary equipment.

The tests provide accurate measurements according to IEC 61992-2 (200 A/sec slope).

Options of the BALTO series

The BALTOWin software is available for retrieval and processing of test results on any Windows system. This includes the test result values and result graphs, and offers exporting to Excel and PDF file formats.

A BALTO calibration tool is available for guided recalibration of the BALTO system by the user.

Additionally, there are tools for easy handling of the BALTO modular, breaker connections and different types of bus-bar systems. Hardware and software customization may be available on request.

Secondary injection test equipment

The BALTO CONTROLLER enables quick and easy testing of DC protection relays. It provides outputs ranging from 0-60mV to 0-10V, as well as ±20mA and 4-20mA current loops.

The product offers flexible simulation of current patterns, including curves from standard BALTO tests, exponential curves, and broken line curves for testing functions such as di/dt, DDL + Delta I and DDL + Delta T.

The BALTO CONTROLLER can be used in conjunction with the BALTO Modular, and its supported vendors include Sécheron, Siemens and RwayTech.

See also

Note: for the latest information please visit the Megger pages for the BALTO Modular and BALTO Compact.

Brochure (PDF): English Deutsch Français Nederlands Italiano Español

Videos (2018):
Products Overview
BALTO Modular
BALTO Compact
BALTO Controller
BALTO Master/Slave
BALTO Testbench

Video (2013): English Deutsch