Bumpless transfer
Switching a controller between manual and automatic without the output jumping.
What it means
Bumpless transfer means the controller initialises its internal state when the mode changes so that the output does not step. Without it, switching to automatic hands the process a sudden output change it did not need.
It matters for diagnosis as well as operation: if you cannot switch to manual and back cleanly, the manual test that separates loop-generated cycling from external disturbances becomes an upset in its own right.
Related
Glossary
Where this comes up
Last reviewed 2026-08-01.