kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
The nuts and bolts of the issue here is the motor is TEFC (totally enclosed fan cooled). Slowing the motor down with a VFD means that cooling fan won't move as much air as it does at full speed - this could result in higher surface temperature on the motor - which temperature is an ignition concern in a hazardous location. If the motor were designed to operate below ignition point even if running on the VFD it might be ok. Said motor might also be ok to use on a drive if not in a hazardous location. It is the hazardous location that creates the concerns here.
Though not in a hazardous location, I have installed inverter duty motors on drives before that had an aux cooling motor/fan integrated into them simply because the thing was normally run at low enough speed a typical TEFC wasn't going to produce enough cooling air flow at low speeds.
I imagine there may be such things out there for hazardous locations as well.
Though not in a hazardous location, I have installed inverter duty motors on drives before that had an aux cooling motor/fan integrated into them simply because the thing was normally run at low enough speed a typical TEFC wasn't going to produce enough cooling air flow at low speeds.
I imagine there may be such things out there for hazardous locations as well.