Owner's manual

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 Page Topic Page
Alpha Test Mode 259
Resolver Cable Balance Tuning Test 282
Analog Input Configuration 262 Resolver Type Selection 283
Current / Speed Curve 264 S-curve Configuration 284
Drive Reference and Feedback Scaling 265 Scale Blocks 286
Droop Compensation 271 Speed Regulation Functions 287
Field Weakening Mode Configuration (v1.006) 271 Speed / Torque Mode Selection 294
PID Function 275 Start At Powerup 300
Reference Control 280 Fine Tuning the Regulators 301