One common problem encountered in high voltage transmission units is the appearance of hotspots on high voltage transmission lines. This phenomenon occurs due to an increase in either the electrical current or resistance values. In high voltage transmission systems, there are fluctuations in electrical current according to power consumption patterns and system adjustments by load dispatchers. The rise in resistance values at jumper clamps and connectors also contributes to the increase in temperature or hotspots at the connectors

The causes of this increased resistance can include improperly fitted nuts and bolts, the presence of pollutants on the clamps, rust on the clamps, and poor clamp tightness.

A frequent issue found in power plant transmission systems, as depicted in the above image, is the absence of grease or the use of general-purpose grease. Consequently, hotspots can occur at temperatures exceeding 45°C, and electrical resistance can spike above 100 micro ohms. This leads to more frequent maintenance requirements, ranging from once every 1-3 months.

Solution

The solution to protect clamps from pollutants, rust, and poor tightness is to use conductor grease, a type of grease that can conduct electricity or heat effectively while also protecting the clamps from contaminants and rust.

Generally, grease acts as an insulator (lacking the ability to conduct electricity and heat well), which can cause hotspots and short circuits. For outdoor applications, most greases do not have good rust protection and cannot dissipate heat effectively.

Eonchemicals offers a solution product called Molykote HSC Plus (paste), which is effective in addressing hotspots and electrical resistance at PLN substations. This conductor grease has the following features and benefits:

• It can reduce electrical resistance and has good conductivity.
• It can dissipate heat effectively, thereby reducing the risk of hotspots.
• It has a good corrosion inhibitor.
• Consequently, maintenance intervals can be extended to once a year

Contact us for further consultation.