Appendix c, Application notes, Alpha test mode – Rockwell Automation 20P PowerFlex Digital DC Drive User Manual
Page 259: Appendix
Rockwell Automation Publication 20P-UM001I-EN-P - February 2013
259
Appendix
C
Application Notes
Alpha Test Mode
The Alpha Test is a diagnostic function that allows you to activate the Armature
or Field power module in an open loop mode. By commanding a SCR firing angle
(specified in Par 167 [Arm Test Angle] or Par 168 [Fld Test Angle]) a voltage is
produced at the output of the selected power module. A load greater than
500 mA is required for proper SCR operation - typically, an incandescent bulb or
inductive load (never a motor) is used.
The Alpha Test is started as soon as Par 166 [Alpha Test] is set to 1 “Arm Fwd”
(armature forward), 2 “Arm Rev” (armature reverse), or 3 “Fld Fwd” (field
forward). The HIM displays "ArmAlphaTest" or "FldAlphaTest" while active.
Start and Jog commands have no affect and a motor contactor is not closed when
the test mode is initiated.
The Alpha Test ends when Par 166 [Alpha Test] is set to 0 “Off ”. Otherwise, only
a digital input Enable or a Fault will stop the test - a HIM Stop has no affect.
Changing the Alpha Test Mode (set in Par 166 [Alpha Test]) resets both test
angles to their minimum firing value (180 deg).
Note: Overcurrent and Overvoltage fault protections are active during these
tests. Also, the Autotune function is disabled while Alpha test is enabled.
Topic
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Topic
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Resolver Cable Balance Tuning Test
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