TYPE E Self Protected Motor Controller

[robbm]

i normally use contactors and motor circuit protectors together to form a self protected motor controller (so as to follow UL508A and eliminate the need for additional fuse protection). i've also seen this listed as a 'TYPE E' motor controller...does a type e motor controller mean strictly that it is self protected or is the definition more broad? (somewhere that has an actual defintion of a type e controller would be great)

 

[MotoDrv]

I just had a guy from WEG in here for a dog and pony show on their control line including Type E and Type F offerings (They bought the old AEG line and now produce it themselves) here is the breakout:

A - Type A combination motor controller consisting of a disconnect switch, fuses, motor controller and overload relay

C - Type C combination motor controller consisting of Inverse time circuit breaker, motor controller and overload relay

D - Type D combination motor controller consisting of instantaneous trip circuit breaker, motor controller and overload relay

E - Type E (self-protected) combination motor controller consisting of manual self-protected combination motor controller and motor controller

F - Type F combination motor controller consisting of manual self-protected combination motor controller and motor controller

 

[MotoDrv]

To add on to the above, I think you are bouncing between the Type F and Type E. The key difference is the E has to be able to identify the trip as either Overload or Short Circuit.

 

[jraef]

Who / what is the source for these "types"? IEC, NEC, NEMA?

JRaef.com
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[Mobius44]

JRaef-
UL508 defines these types. The linked document does a nice job explaining the different types.

http://ecatalog.squared.com/pubs/Motor Control/Combination Starters, NEMA Style/8538DB0401.pdf

 

[MotoDrv]

UL508 is correct. The UL Type E also means that the build up of parts (manual motor protector, contactor, OL and Short Circuit signaling block etc) have all been tested and certified per UL to be self-protected. A type F build up might be exactly the same as a Type E but it is not tested and certified by UL to be self-protected so I guess the simple answer is only a Type E per UL508 is truely self-protected.