News | company news | Aug 26,2026
North Africa is investing heavily in electricity transmission, electrical substations, grid connections for renewable energy, and distribution infrastructure. For electrical engineers involved in these projects, current transformers are essential components for metering, billing, and energy monitoring, as well as for protection functions.
High-voltage current transformers are essential for the protection of transmission lines and substations. However, many power generation, industrial, and renewable energy facilities also include large-scale low-voltage systems. These systems require low-voltage current transformers (LVCTs) that meet the necessary technical requirements.
For engineers working on projects in Egypt, Morocco, Algeria, and other North African countries, selecting a suitable low-temperature current transformer (LTCT) involves more than simply matching the turns ratio. They must also consider the application context, rated voltage, accuracy class, load, secondary current, conductor cross-section, installation method, and project specifications.
Low voltage current transformers used in North African projects for energy metering, power monitoring and low voltage electrical systems.
A low voltage current transformer (LVCT) is a current transformer designed to measure current in low voltage alternating current systems.
It converts a relatively high primary current into a lower, standardized secondary current, which can be connected to instruments, control units, relays, or other measuring devices.
The terminology varies depending on the market:
Engineers should not assume from the outset that these terms are technically identical. Rated voltage, accuracy, load, transformation ratio, insulation class, and applicable standards must always be verified against the project specifications.
The HEYI LMZ-0.5 and LMZJ-0.5 series current transformers are low-voltage internal transformers for AC circuits with rated voltages up to 0.5 kV and rated frequencies of 50/60 Hz. The product documentation describes their applications in detail, including current measurement, energy measurement, monitoring, and relay protection.
Energy projects in North Africa are often described as high-voltage transmission infrastructure. However, large substations, renewable energy production facilities, and power companies constitute multiple electricity supply systems operating at different voltage levels.
Here are some examples of electricity transmission projects:
High-voltage transmission system → Transformer → Low-voltage auxiliary system → Low-voltage switchgear → Electrical load
The high voltage section may require separate high voltage current transformers for protection and voltage measurement, and the low voltage section may require low voltage current transformers for energy measurement and power control .
This distinction is particularly important in North Africa.
The Egyptian Electricity Transmission Company is implementing a national program to modernize and expand the electricity grid. Supported by the European Investment Bank, this program includes the construction of new substations and transmission lines to facilitate the integration of renewable energy into the national grid. The goal is to connect 22 gigawatts of renewable energy to the grid by 2030.
The plan includes infrastructure measures for solar and wind power production, particularly in the Red Sea and Gulf of Suez regions.
For electrical engineers, this means that in addition to high-voltage transmission systems, low-voltage measurement points can also be installed there:
Therefore, the sizing of low voltage current transformers must be based on the actual conditions of the low voltage circuit and not on the overall nominal voltage of the transmission project .
Morocco is also developing its electricity transport infrastructure.
ONEE’s electricity transmission infrastructure development plan, supported by the European Investment Bank, covers the period 2024-2029 and includes national projects for the construction of electricity transmission lines at voltages ranging from 60 kV to 400 kV . This plan aims to strengthen and expand transmission infrastructure, improve security of supply, meet electricity demand, and integrate more renewable energy sources.
The presence of high-voltage infrastructure does not eliminate the need to carry out low-voltage measurements.
In substations, renewable energy power plants, and electrical buildings, engineers may require low-voltage current transformers (CTs) for the following reasons:
Therefore, when evaluating low voltage current transformers in Morocco, engineers must determine the exact low voltage measurement point, rather than selecting a current transformer based on the maximum system voltage of the project.
Algeria is developing its electricity transport and distribution infrastructure.
In its latest infrastructure development plan, Sonergaz announced the commissioning of six new transformer stations with a nominal voltage of 400/220 kV and 220/60 kV, six high-voltage transformer stations and 35 high-voltage lines with a total length of 945 km.
At the distribution network level, this same system includes a 2,115 km long distribution network and 622 medium/low voltage substations.
Sonelgaz also reported on projects related to 400/220 kV, 220/60 kV, 220/30 kV and 60/30 kV substations.
The combination of energy transport and distribution technologies has generated numerous potential applications for power transformers.
For long-term care service providers, the most pressing business opportunities are generally found in the following areas:
Medium/low voltage distribution → Low voltage switchgear → Industrial installations → Auxiliary systems → Energy monitoring
Instead of the main protection circuit at 400 kV or 220 kV.
Low voltage current transformers can be used in various electrical systems.
Low voltage distribution boxes are among the simplest devices.
Low-voltage current transformers can be installed on the supply or return lines to provide the following current information:
For electrical equipment manufacturers and general contractors, the physical dimensions of current transformers are as important as their electrical parameters.
One of the most important applications is the measurement of energy consumption .
If the primary current is too high to be connected directly, a current transformer allows the measuring device to measure the current indirectly .
Depending on the technical requirements of a project, engineers may need different levels of precision.
The HEYI documentation for LMZ/LMZJ clearly states:
This applies to the corresponding configuration.
Therefore, this product can be used in the following areas of application:
However, the final precision must always be chosen according to the characteristics of the instrument and the project.
Current transformers are used to monitor the power supply . They are typically used when engineers need continuous information about electrical loads.
Typical application areas include:
These application areas are described in detail in the LMZ/LMZJ product documentation.
When monitoring energy consumption, engineers must consider not only peak current, but also normal operating current and the required measurement accuracy.
Busbar current transformers are another important application in low-voltage distribution systems.
The CT monitor display window must be large enough to accommodate the main body or power rail.
The LMZ/LMZJ series from HEYI offers windows of different sizes, suitable for large diameter cables or bus bars.
Before selecting a busbar current transformer, the engineer must check the following points:
If the current transformer has the correct transformation ratio, but the window size does not meet the requirements, it cannot be installed correctly.
The first step is to determine the necessary ratio between primary and secondary education.
For example:
The LMZ/LMZJ product range includes different configurations, from 5/5A to 5000/5A, depending on the model and configuration.
The chosen scale must meet the requirements of the actual electrical system and the connected measuring instruments.
Engineers should not automatically choose the highest possible ratio.
When measuring energy, it is important to choose a ratio that guarantees sufficient measurement accuracy within the normal operating range.
Current measuring transformer .
The common configurations are:
The required class depends on the specific application.
For example:
General surveillance
→ Perhaps it will be enough to reduce the accuracy requirements.
Energy measurement
→ Greater precision in measurements may be required.
Income or high-precision measurement
→ The project specifications may stipulate certain levels of measurement.
Therefore, engineers must select the level of accuracy based on the entire measurement system and not consider the current transformer as an isolated component.
If the secondary current is not specified, the current conversion ratio is incomplete.
For example:
500/5A
Procedure:
The secondary output signal must be compatible with the connected instrument, relay, sensor, or control unit.
When choosing a cryogenic current transformer for many electrical and industrial measurement systems, a secondary current of 5 A is an important parameter.
The load of a current transformer is the load connected to its secondary circuit.
Total incidental charges may include the following:
It is therefore necessary to choose a current transformer that is compatible with the load and the entire secondary circuit.
The LMZ/LMZJ product documentation contains the load specifications relating to accuracy and applicable translation ratios.
The LMZ/LMZJ series is designed for use in systems with a nominal voltage of 0.5 kV or less and an operating frequency of 50/60 Hz.
This parameter is of paramount importance.
For example, engineers should not choose a low voltage current transformer (LTCT) with a nominal voltage of 0.5 kV as the primary current transformer for a 220 kV or 400 kV transmission line.
However, engineers must determine the exact circuit in which the current transformer will be installed.
This is particularly important in large energy projects where high and low voltage systems coexist in the same location.
The following distinctions are useful in determining the need for computed tomography in projects in North Africa.
| volume | low voltage/low current transformer | high voltage transformer |
| Typical application areas | Low voltage power distribution and equipment | High-voltage power lines and electrical substations |
| For example, the tension | LMZ/LMZJ ≤ 0.5 kV | 60 kV, 110 kV, 220 kV, 400 kV and more |
| Typical functions | Measurements, metrology, monitoring | High voltage protection and measurement |
| Install | Low voltage distribution boards, distribution cabinets and equipment. | Automation information systems (AIS), switchgear, transformers, high-voltage switchgear |
| dominant body | cable or busbar | high voltage conductors/systems |
| Select a key | Relationship, precision, load, window | Protection factor, protection class, load, insulation and system design. |
The most important engineering principle is:
When choosing a current transformer, it is necessary to consider the actual conditions of the installation circuit, and not just the overall voltage level of the project.
The HEYI LMZ-0.5 and LMZJ-0.5 series are designed for indoor use in AC circuits with a rated voltage of up to 0.5 kV.
This product range offers different current and accuracy options to meet different measurement needs.
The documented application areas include:
This product range includes configurations from 5/5A to 300/5A, higher current configurations from 400/5A to 600/5A and even higher current configurations, up to 5000/5A.
This product range also includes fixed panel mounting systems and offers enclosures and windows of various sizes to accommodate various cables and bus lines.
When implementing infrastructure projects and turnkey projects in North Africa, engineers must consider the following workflow:
Check if the measurement point is as follows:
Check if a scanner is necessary in the following situations:
confirm:
confirm:
When implementing projects in the utilities sector, the final selection must be based on approved project specifications, equipment interface requirements, applicable standards, and customer requirements.
Egypt, Morocco and Algeria are currently building large-scale infrastructure for the transport and distribution of electricity.
Egypt’s plan to modernize the electricity grid aims to expand and modernize the electricity transmission network and integrate renewable energy sources.
ONEE’s electricity development plan in Morocco includes infrastructure in the voltage range of 60 kV to 400 kV, including transmission lines and substations linked to new renewable energy projects.
The Algerian company Sonegaz recently launched a project that combines the construction of high-voltage power lines with the large-scale expansion of medium and low-voltage distribution networks.
This opens up real opportunities for suppliers of low-voltage current transformers:
Large-scale public service projects
↓
Renewable energy production stations/installations
↓
Auxiliary and power distribution systems
↓
Low voltage distribution panel
↓
Current measurement/monitoring
↓
low voltage transformer
This is the appropriate technical link between large energy projects and long-term money transfer payment applications.
The expansion of electricity transmission networks, the connection to renewable energy networks and the distribution infrastructure in North Africa have generated a need for measurement and control technologies at different levels of electricity supply.
Low voltage current transformers (LVCTs) cannot replace high voltage current transformers used on 220 kV or 400 kV transmission lines. However, they fulfill a different, but equally important, function in low voltage power distribution, auxiliary power systems, switchboards, industrial installations, as well as in energy metering and monitoring.
In Egypt, Morocco, Algeria and other North African countries, the appropriate selection process must begin with the precise location of the installation and the electrical characteristics.
The most important parameters are as follows:
HEYI’s LMZ-0.5 and LMZJ-0.5 low voltage current transformers offer various conversion and accuracy options, and are suitable for a wide range of low voltage AC applications, including current measurement, power measurement, monitoring, and relay protection.
For a specific project, the engineer must provide data on primary current, secondary current, rated voltage, accuracy class, load, frequency and cable or busbar dimensions in order to evaluate the appropriate configuration of the low voltage current transformer/LTCT.
Compay：HEYI Electrical Co., Ltd.
Brand: HEYI/ASCT
Contact: Bethy
E-mail: heyi@heyiele.com
Tel: 86-13968747975
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