Tough insulation resistance testers

Electrical Power & Protection

April 2014 Electrical Power & Protection

The MIT515 (5 kV), MIT525 (5 kV) and MIT1025 (10 kV) are the newest in Megger’s line of insulation testers over 1 kV. These instruments are based on Megger’s extensive knowledge of insulation testing – over 100 years of exper-ience – as well as feedback from actual end-users. Megger has taken the best insulation testers in the world and added functionality to make them easier to use and transport. They include Megger’s patented digital/analogue display with real-time pointer movement, a CATIV safety rating at all terminals and a unique dual-case design.

The new range of insulation resistance testers consists of three models: two 5 kV units (MIT515 and MIT525) and a 10 kV unit (MIT1025). Resistance measurement is available up to 10 T for the 5 kV models and 30 T for the 10 kV model. The new instruments are smaller and lighter than previous models yet offer advanced features and rapid charge capability. A key productivity feature is the ability to take measurements when connected to line power or mains with a dead battery. Intelligent battery charging ensures the optimum charge rate as a function of battery level, resulting in minimum charge times.

The rugged, unique dual-case design provides the ultimate protection for a portable instrument, and a clip-on lead pouch ensures that leads remain with the instrument at all times. The case lid is removable for improved terminal access. IP rating is IP65 with the case closed. High reliability and safety are built in; all models are safety rated to CATIV 600 V and are double insulated.

Five pre-set voltage ranges are provided in insulation test mode, plus a user-settable lock voltage range. Any selectable test voltage may be locked and restored via the selector switch, thereby increasing efficiency of commissioning and repetitive tests. Preconfigured diagnostic tests include polarisation index (PI), dielectric absorption ratio (DAR), dielectric discharge (DD), step voltage (SV) and ramp test. Graphs can be compared to example curves in IEEE 95-2002 to reveal a variety of faults otherwise difficult to detect. Small defects can be easily detected without risking the sudden large voltage increments produced by a step voltage test.

Monitoring the developing graph during the test enables the operator to terminate prior to breakdown, thereby reducing the possibility of damage to an already flawed insulation. These units are particularly informative on polyester, asphalt and epoxy-mica insulations. They can also test voltage suppression devices. Simplicity of operation is achieved with two rotary switches and the large backlit display enables multiple results to be displayed simultaneously.

Advanced memory storage includes time/date stamping of results, logging of data and recall of results to screen. A fully isolated type B USB device interface is used for safe transfer of data to Megger’s PowerDB asset management software. Typical end users include electrical contractors, testing and service companies, wind farm and solar generation operators, power generation and distribution companies, as well as industrial and rail companies.

For more information contact Stuart Ashton, Surgetek, +27 (0)11 792 1303, [email protected], www.surgetek.co.za

Share this article:

Empowering Africa’s renewable energy future
Electrical Power & Protection
As a global leader in renewable energy technology, SUNGROW has pioneered sustainable power solutions for over 28 years. At the recent Africa Energy Indaba 2025, SUNGROW showcased its advanced energy solutions designed to meet the diverse needs of the African continent.

Read more...

The role of electromechanical solutions in supporting Africa’s industrial growth
Electrical Power & Protection
Africa’s industries are transforming rapidly. Fuelled by a huge demand for energy connectivity, better infrastructure, increased manufacturing and responsible resource management, electromechanical solutions are key to shaping this growth, allowing industries to scale up their operations efficiently and sustainably.

Read more...

Empowering South Africa’s IPPs for a renewable future
Electrical Power & Protection
Many crucial parts of the economy of the future will be hugely energy intensive, foremost amongst which will be electrified transport and the large data processing required by automation and AI. Successful economies will be those that can ensure businesses and investors have access to a stable supply of low-cost renewable energy. South Africa has the opportunity to become a global leader in this regard.

Read more...

Sustainable mining operations escalate as demand for critical materials to double
Electrical Power & Protection
The mining sector is at the forefront of the energy transition due to its role in extracting essential materials and minerals necessary for green technologies. As demand for renewable energy, electric vehicles and other sustainable technologies increases exponentially, so will the demand for these necessary materials.

Read more...

Monitoring partial discharge on medium voltage switchgear
Schneider Electric South Africa Electrical Power & Protection
Schneider Electric South Africa has launched its EcoStruxure Service Plan (ESP) in the Anglophone African region for medium voltage (MV) switchgear

Read more...

Raptor switches
Phoenix Contact Electrical Power & Protection
The Phoenix Contact Raptor switches enable reliable and safe operation in extreme ambient conditions. The managed switch portfolio meets the stringent requirements of IEC 61850-3 and IEEE 1613 standards and is ideal for critical infrastructure and power supply applications.

Read more...

Electrical safety warning indicators
Electrical Power & Protection
Remlive electrical safety warning indicators have been keeping the workplace safe for more than 25 years.

Read more...

Self-contained standalone lightning warning system
Senseca Electrical Power & Protection
The BTD-200 lightning warning system from Biral (UK) is a complete detection and warning system. Its highly specialised aviation grade lightning detection technology delivers the warning as soon as lightning is detected and before the first strike.

Read more...

Half brick second generation converter
Vepac Electronics Electrical Power & Protection
The Supreme series half brick second generation converter from Vepac is composed of isolated, board-mountable, fixed switching frequency DC-DC converters that use synchronous rectification to achieve extremely high power conversion efficiency.

Read more...

Electrical Power & Protection

Tough insulation resistance testers

Further reading:

Published by Technews