Shimadzu Spd20a User Manual Page

Before diving into the user manual, let's take a look at the key components and features of the Shimadzu SPD-20A:

A fundamental step prior to sample injection is the "Auto-Zero" function. As outlined in the operational protocols, the detector measures the absorbance of the mobile phase continuously. Before the sample enters the flow cell, the instrument must establish a zero-absorbance baseline. The Auto-Zero command electronically sets the current absorbance to 0.000 mAU. This must be performed when the mobile phase composition is stable and the flow rate is constant. Failing to auto-zero can lead to inaccurate peak area calculations and integration errors. shimadzu spd20a user manual