How can one troubleshoot a S-Flex 212 Drive if it will not run in AFC nor Bypass?


28 September 2021

S-Flex 212 troubleshooting while it cannot run on AFC nor Bypass

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.