The purpose of the test:

Testing of RexVa PTC Self 80 heating film in overheating condition.
Comparison of RexVa PTC Self 80 film with another manufacturer's PTC film.

Testing method:

Films are connected to the network 220 volts without temperature controller.
The films are located temperature sensors at an equal distance from the edges.
Films are covered with Monolium flooring and a carpet.
Duration of testing 3 hours 30 minutes.

Test results:

The RexVa film holds a lower temperature than Company A, and don't get overheated.
The temperature difference between the sensors is noticeably higher for Company A, with less uniform heating.

Reasons for the success of the Rexva Self80 heating film

Carbon paste Unique, patented technology of production of carbon paste and quality equipment allow printing carbon layer on the film with uniform thickness, so that the temperature of our film has minimal differences across the width.
Silver Busbar. This silver Busbar reduces the energy loss along the entire length of the RexVa film. In the RexVa PTC Self 80 film, we use an exceptionally solid 18 mm thick silver Busbar.
Copper Busbar. In our film we use 15 mm wide copper Busbar, which also has a positive effect on the durability and temperature of our film.

Restore rate test.

1. One of the main indicators of PTC film quality is the restoration function that returns the heating value to its original state after local overheating.
2. When the temperature rises due to local overheating on the PTC film, the resistance value increases to suppress the flow of current and to control the temperature.
3. When the power is turned off and the temperature drops, the resistance value should return to the state before the heat generation, and there should be no abnormality in heat generation.
4. After local overheating, if the resistance value is higher than the existing, the heating temperature is low due to the decrease in the wattage value.

The film should return to its initial values in 24 hours at room temperature. To speed up this process, we measure the resistance of the film immediately after the test for local overheating and place it in a conditioned room with a temperature of 20 ° C.

You can see the measurement results in the table below:

Measurement results:

By the data we can see that RexVa heating film has been stable, not allowing overheating above 80 °C and stably returning to the beginning of resistance after overheating. Films from other companies analyzed as part of the testing are having trouble keeping overheating within safe limits. Also, after the tests they greatly change the resistivity values, respectively, and as result power of the film, its economy.