GE AF-650 GP Series, Design Manual

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3.3.1 Reference Limits
Par. F-50 Reference Range , par. F-52 Minimum Reference and par. F-53 Maximum Reference together define the allowed range of the sum of all references. The
sum of all references are clamped when necessary. The relation between the resulting reference (after clamping) and the sum of all references is shown below.
The value of par. F-52 Minimum Reference can not be set to less than 0, unless
the par. H-40 Configuration Mode is set to [3] Process. In that case the fol-
lowing relations between the resulting reference (after clamping) and the sum
of all references is as shown to the right.
3.3.2 Scaling of Preset References and Bus References
Preset references are scaled according to the following rules:
• When par. F-50 Reference Range : [0] Min - Max 0% reference equals 0 [unit] where unit can be any unit e.g. rpm, m/s, bar etc. 100% reference equals
the Max (abs (par. F-53 Maximum Reference ), abs (par. F-52 Minimum Reference )).
• When par. F-50 Reference Range : [1] -Max - +Max 0% reference equals 0 [unit] -100% reference equals -Max Reference 100% reference equals Max
Reference.
Bus references are scaled according to the following rules:
• When par. F-50 Reference Range : [0] Min - Max. To obtain max resolution on the bus reference the scaling on the bus is: 0% reference equals Min
Reference and 100% reference equals Max reference.
• When par. F-50 Reference Range : [1] -Max - +Max -100% reference equals -Max Reference 100% reference equals Max Reference.
AF-650 GP Design Guide
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