1. R1SE-0515/H2-R Substitution Conclusion The R1SE-0515/H2-R is generally compatible with the original part in terms of key I/O parameters (5V input, 15V/~66mA output) and package footprint, making it a potential substitute. However, two critical differences must be noted: First, the isolation voltage is reduced from 3kV to 2kV, which lowers its capability to withstand high-voltage transients or meet stringent isolation safety margins. It is therefore more suitable for applications with less demanding isolation requirements. Second, efficiency drops from 83% to 76%, increasing the module's internal power dissipation by approximately 30%. This may lead to higher temperature rise in confined or high-ambient environments, requiring assessment of the thermal design margin. If the actual application does not impose strict demands on isolation withstand voltage and thermal performance, this model can be considered a direct replacement.