Now you need to define where your references will come from. This is done in the 3-1 parameter group.
Parameters 3-10, 3-15, 3-16 & 3-17 are all parameters will that allow you set up your reference sources.
If you want to use multiple reference points, then you must define them here. Most applications will
only use one reference terminal rather than multiples. If this is the case then set the single reference
source in 3-15, and program all other resources to “No Operation”. This is good practice because of the
“Sum” function described earlier. If other terminals are programmed as reference resources but not
actually used, any electrical noise that might ride on those terminals will be summed into the equation.
After the reference sources have been defined, the next step is to scale them. The analog inputs are
programmed in parameter group 6. For the example above, analog input 53 must now be scaled. You
will need to set a low and high voltage or current as well as a low and high reference value. See below;
Be aware that if multiple reference sources are chosen, then each can be scaled individually to
contribute the desired portion of your maximum reference. For example, AI 53 = 0-10 V = 0-50 Hz &
AI 54 = 0-10 V = 0-10 Hz. Now AI 53 will command the first 50 Hz and AI 54 will act as a trim for the
last 10 Hz.
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