EXFO IQS-1700 High Performance Power Meter for IQS-500/600 - Manual (Page 37)

Setting Up Your High Performance Power Meter
High Performance Power Meter 29
Setting the Display Resolution
If you have previously selected watts as units, the Display Res. list will
be grayed out (as illustrated above).
3. Click Apply to confirm your new setting.
Note: You can also use the All Channels button to modify all channels at once. If
other values were set previously, but are different from those you are
currently setting, any value you change will turn red to indicate that it is
different.
Note: When W or W/W is selected, the display resolution changes to Auto (the
appropriate W unit will be used according to the power of the signal
detected). It is then impossible to access the display resolution list.