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What troubleshooting can I do if the S-Flex drive will not run in AFC or Bypass?

I cannot run the motor in Drive or Bypass modes.

Product line:
SFD212, S-Flex

All models with Bypass option. 


Locate the overload mounted onto the Bypass Contactor (BC).  You should see a small blue reset button.  Trying pushing that button to see if the overload was tripped.

On top of the Drive Output Contactor (DOC), there is an auxiliary contact block, LADN**, mounted on top.  Check to see if that block is seated properly and can move freely. 

If still not running check for 120VAC from the control power transformer (CPT), terminals X1-X2.  Then check for 120VAC from XF to X2 to make sure the secondary fuse on the CPT is still good. 

Confirm contact closures from terminals #1-#2 (Smoke Purge option), #2-#3 (Firestat/Freeze interlock), #3-#4 (End Damper Control).  With the selector switch in AFC, you should have 120VAC from X2 on the CPT to terminal #4.  In Bypass mode, you should have 120VAC from X2 on the CPT to terminal #6. 

If still not able to locate the missing connection, contact the Drive Products Support group.  Have the Q2C Code or FO number from the nameplate available. 
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