- Joined
- Jan 14, 2013
- Messages
- 62
The switch I bought I got on ebay its a 30 amp industrial 220 switch. I may just go with the fuse disconnect because it has a throw switch and I can use the throw switch for the off/on.
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VFD install question
- Thread starter Great white hunter
- Start date
The switch I bought I got on ebay its a 30 amp industrial 220 switch. I may just go with the fuse disconnect because it has a throw switch and I can use the throw switch for the off/on.
- Joined
- Sep 11, 2012
- Messages
- 329
My oh my where does some of this information come from?
The OFF/ON switch you are trying to refer to, and the instructions refer to is the disconnect switch for the POWER to the VFD. Not the OFF/ON for the CONTROL of the VFD.
Disconnect switches come in many flavors, mainly fused and unfused. They are next rated by duty, standard duty, 240v or less or heavy duty 480v or less. Next rating is amperage, next rating is duty. In most of our cases you want a motor duty rated switch. Not a two pole residential 15/20 amp switch even though they may LOOK identical. A switch rated for inductive load.
Breakers as built for residential type installation have two trip elements, thermal-for overload protection, and magnetic-for short circuit protection. They do not weaken with use, how ever they are not rated to be used as switch duty unless so marked. Breakers rated for motor duty, say like your air conditioner, are marked as rated for HVACR (heating, ventilation, air conditioning rated).
Primary line filters are to keep the harmonics and other produced electrical noise from the VFD from going up stream and affecting all other circuits in the source panel. Like you turn your lathe on and your wifes TV or computer screen gets fuzzy. It can actually go out your service lines to the Xfmr and affect every service common to the drop. Wire is wire and those electrons don't know where to stop. Once it hits the core of the primary transformer it is pretty well contained, but not completely. That is why the power company dings customers for poor power factor. Your bad electricity habits are seen all the way to the source.
Secondary line filters between the drive and the motor are there again to contain electrical noise and problems to the realm of the VFD. Like conductor heating when the wire is no where close to its maximum rating.
Line contactors are wired in by engineers on these schematics to give a path of power around the VFD should it fail so as not to disable a production line or such.
Please guys do not confuse primary power and control power. Two different pigs in the same pen but they seldom mate. Use a non fused disconnect switch by the machine to kill power to the equipment for servicing, safety, or to put it to sleep until the next use. By placing fuses here, you are creating another place to create a potential problem when something fails. Blown, or partially blown fuse. You don't need them. Toggle switches for this use are made to be mounted in a standard electrical enclosure and accepting a standard electrical cover of some sort. UL and the electrical industry do not like the ordinary person creating electrical devices. Install your VFD bare bones, if a problem rears its head address it later when you know what to do. Saves time and money.
All the ratings I speak of are written on the device or the paperwork that accompanies it in its box.
The OFF/ON switch you are trying to refer to, and the instructions refer to is the disconnect switch for the POWER to the VFD. Not the OFF/ON for the CONTROL of the VFD.
Disconnect switches come in many flavors, mainly fused and unfused. They are next rated by duty, standard duty, 240v or less or heavy duty 480v or less. Next rating is amperage, next rating is duty. In most of our cases you want a motor duty rated switch. Not a two pole residential 15/20 amp switch even though they may LOOK identical. A switch rated for inductive load.
Breakers as built for residential type installation have two trip elements, thermal-for overload protection, and magnetic-for short circuit protection. They do not weaken with use, how ever they are not rated to be used as switch duty unless so marked. Breakers rated for motor duty, say like your air conditioner, are marked as rated for HVACR (heating, ventilation, air conditioning rated).
Primary line filters are to keep the harmonics and other produced electrical noise from the VFD from going up stream and affecting all other circuits in the source panel. Like you turn your lathe on and your wifes TV or computer screen gets fuzzy. It can actually go out your service lines to the Xfmr and affect every service common to the drop. Wire is wire and those electrons don't know where to stop. Once it hits the core of the primary transformer it is pretty well contained, but not completely. That is why the power company dings customers for poor power factor. Your bad electricity habits are seen all the way to the source.
Secondary line filters between the drive and the motor are there again to contain electrical noise and problems to the realm of the VFD. Like conductor heating when the wire is no where close to its maximum rating.
Line contactors are wired in by engineers on these schematics to give a path of power around the VFD should it fail so as not to disable a production line or such.
Please guys do not confuse primary power and control power. Two different pigs in the same pen but they seldom mate. Use a non fused disconnect switch by the machine to kill power to the equipment for servicing, safety, or to put it to sleep until the next use. By placing fuses here, you are creating another place to create a potential problem when something fails. Blown, or partially blown fuse. You don't need them. Toggle switches for this use are made to be mounted in a standard electrical enclosure and accepting a standard electrical cover of some sort. UL and the electrical industry do not like the ordinary person creating electrical devices. Install your VFD bare bones, if a problem rears its head address it later when you know what to do. Saves time and money.
All the ratings I speak of are written on the device or the paperwork that accompanies it in its box.