DaveEDesign
Member
My company has been having a few problems with motors on VFD's.
It is now believed to possibly be a situation where the motor leads are not adequately secured.
When I look on-line for some packaged solutions, I find very few "approved" solutions, and the ones that do are cumbersome. (Polaris or Burndy style insulated connectors). Either they are not approved for motor use, or are so large to accomodate a 12 lead - 3 phase, 30 HP motor that they won't fit in a motor junction box, due to the fact that the terminals are only rated for one conductor per terminal.
Also, when referring to some documents I found on the internet, "recommended" practices talk about split bolts, wrapped in cambric, then rubber, then vinyl tape and talk about NEC 430.12 & .13 in 2007(?) version of NFPA 70. I only have 2005 NEC, and 430.12 doesn't go in anywhere near that much detail. Besides, when I look at catalogs for split bolts, most aren't rated for multi-wire connections (again, look @ the 12 lead, 3 phase application).
I'll also did a quick review of the overview of UL 486A & B, is this the detail I need ? (I also noticed a UL 486E, which actually mentions motor connections).
Anyway, I know that I can't get an exact recommendation, but all I want to do is to hook-up 3 phase motors in a fool-proof manner;
Can anyone give a place to look to find the proper documentation? Perhaps trade magazines that show the practices with mentions to proper codes?
It is now believed to possibly be a situation where the motor leads are not adequately secured.
When I look on-line for some packaged solutions, I find very few "approved" solutions, and the ones that do are cumbersome. (Polaris or Burndy style insulated connectors). Either they are not approved for motor use, or are so large to accomodate a 12 lead - 3 phase, 30 HP motor that they won't fit in a motor junction box, due to the fact that the terminals are only rated for one conductor per terminal.
Also, when referring to some documents I found on the internet, "recommended" practices talk about split bolts, wrapped in cambric, then rubber, then vinyl tape and talk about NEC 430.12 & .13 in 2007(?) version of NFPA 70. I only have 2005 NEC, and 430.12 doesn't go in anywhere near that much detail. Besides, when I look at catalogs for split bolts, most aren't rated for multi-wire connections (again, look @ the 12 lead, 3 phase application).
I'll also did a quick review of the overview of UL 486A & B, is this the detail I need ? (I also noticed a UL 486E, which actually mentions motor connections).
Anyway, I know that I can't get an exact recommendation, but all I want to do is to hook-up 3 phase motors in a fool-proof manner;
Can anyone give a place to look to find the proper documentation? Perhaps trade magazines that show the practices with mentions to proper codes?