Rockwell Automation 20A PowerFlex 70EC/700VC - Manual (Page 95)

Safe-Off 91
Safe-Off Refer to “DriveGuard Safe-Off User Manual” publication PFLEX-UM001.
Scale Blocks See also "Analog Scaling" on page 4 and page 10 .
Scale blocks are used to scale a parameter value. [ScaleX In Value] is linked to the
parameter that you wish to scale. [ScaleX In Hi] and [ScaleX In Lo] determine the
high and low values for the input to the scale block. [ScaleX Out Hi] and [ScaleX
Out Lo] determine the corresponding high and low values for the output of the scale
block. [ScaleX Out Value] is the resulting output of the scale block.
There are (3) ways to use the output of the scale block:
1. A destination parameter can be linked to [ScaleX Out Value].
2. [PI Reference Sel] and [PI Feedback Sel] can also use the output of the scale
block by setting them to:
– 25, “Scale Block1 Out”
– 26, “Scale Block2 Out”
Note that when [PI Reference Sel] and [PI Feedback Sel] are set to use the scale
blocks, the [Scale X Out Hi] and [Scale x Out Lo] parameters are not active.
Instead, [PI Reference Hi] and [PI Reference Lo], or [PI Feedback Hi] and [PI
Feedback Lo], determine the scaling for the output of the scale block.
3. [Analog Outx Sel] can be set to:
– 20, “Scale Block1”
– 21, “Scale Block2”
– 22, “Scale Block3”
– 23, “Scale Block4”
Note that when the Analog Outputs are set to use the scale blocks, the [Scale x
Out Hi] and [ScaleX Out Lo] parameters are not active. Instead, [Analog OutX
Hi] and [Analog OutX Lo] determine the scaling for the output of the scale
block. See "Analog Outputs" on
page 10 .
Example Configuration
In this configuration Analog In 2 is a –10V to +10V signal which corresponds to –
800% to +800% motor torque from another drive. We want to use the –200% to
+200% range (–2.5V to +2.5V) of that motor torque and correspond it to –100% to
+100% of the PI Reference.
70EC 700VC 700H
✔
70EC 700VC 700H
✔
-100
-2.5
-1.5
-0.5
0.5
1.5
2.5
-80 -60 -40 -20 0 20 40 60 80 100
PI Reference
Scale1 In Value =
Analog In2 Value (Volts)