If a fuse holder melts but the fuse doesn’t blow, it’s not because your equipment is faulty or drawing too much current, but due to poor contact between the fuse and holder. The added resistance at the connection generates heat, which can worsen over time and cause the holder to melt. For higher currents (20A+), standard blade fuses are inadequate, so use quality options like Mega or Midi fuses to prevent this issue.
Important
In this article we explain the need for testing to determine the cause of the issue. Testing may involve changes to the installation or wiring. For your safety and accuracy, REDARC recommends engaging a REDNetwork member or a suitably qualified auto electrician - Find Your Local Installer
Problem
A fuse holder has melted, but the fuse itself has not blown. Does this mean the equipment is faulty or drawing too much current?
Cause
If the fuse is intact, the equipment is not drawing excessive current. The melting occurs because of poor contact between the fuse and holder. Current flowing through this resistance generates heat. Over time, the heat can oxidise the connection, increasing resistance further and creating a cycle of rising heat until the holder fails. This failure can appear sudden, even after the system has been operating normally for some time.
Solution
For low currents (around 5–10A), standard automotive blade fuses and holders may be sufficient. For higher currents (20A or more), it is essential to use quality fuses and holders designed for the load, such as Mega or Midi fuses. These provide better contact and reduce the risk of overheating and melting.