What Is DC Bias And When Should It Be Tested?
In the context of a transformer or choke, DC bias relates to a constant
current element that is added to the AC signal.
Many wound components must operate with DC currents flowing through
them and, during the design stage, it is necessary to establish that the
component will function correctly with the specified current.
In the case of production testing however, it is possible to confirm
the correct assembly, and therefore correct operation of a wound
component, without applying a DC bias.
However, For best confidence, you should check with DC bias present,
using a DC bias unit such as Dc1000A or at least perform an audit.
The Voltech AT5600 allows for integration of DC1000 and automatic audit
of DC performance.
This tech note discusses the issue in some detail and explains how
production facilities can sometimes identify good components with complete
confidence in the absence of a DC bias generator.