[Willbird]

http://www.wolfautomation.com/Produc...roductID=18805

I bought the above VFD in a 5hp model, I had a grizzly lathe on order that had a 4hp 3 phase motor on it. Got tired of endless back order on the lathe, and I bought a 2hp single phase lathe.

I had been running the bridgeport on a static phase converter since it was new in 1982.

So I put the VFD on the mill, if I ever NEED a 5hp VFD I have one, and can just buy a 2hp for the mill.

The VFD is a HUGE improvement, the mill is a vari speed so I really do not need speed control, if I do it is there however.

I wired it to use the original Bport drum switch to control the motor...works slick.

Bill

[Al_The_Man]

I wired it to use the original Bport drum switch to control the motor...works slick.

Bill

The drum switch is not switching 3 phase is it?
Al.

[Willbird]

No AL.

Originally line power went thru the drum switch to the motor. Now the motor is wired direct to the the VFD outputs.

I used my ohm meter to find terminals in the drum switch to work with the proper terminals on the VFD terminal strip, and wired it up to do that.

I did buy a remote keypad for the vfd but ended up not using it, using the normal Bport drum switch is just hard wired into me after all these years. I may add an E-Stop button of some kind at a later date.

Bill

[mactec54]

Hi willbird

I hope that you are not using the old drum switch to turn the vfd on & off as you would
have been doing before you fitted the VFD as this will destroy the VFD over time you can use the drum switch for a power on/power off to the VFD but when in use you have
to use the on/off Stop/Start that is on the VFD so I would put your remote on so you can do this VFD drives do not like the input power being turned on & off

[Willbird]

Hi willbird

I hope that you are not using the old drum switch to turn the vfd on & off as you would
have been doing before you fitted the VFD as this will destroy the VFD over time you can use the drum switch for a power on/power off to the VFD but when in use you have
to use the on/off Stop/Start that is on the VFD so I would put your remote on so you can do this VFD drives do not like the input power being turned on & off

OK I will explain how it is wired up to save any further confusion.

Line power in, 220 single phase goes into the VFD(I will wire a contacter in between to shut the whole thing OFF when not using the machine so the vfd cooling does not run 24/7/365)

The 3 phase motor on the machine is wired DIRECTLY to the VFD outputs.

The drum switch when switched to FORWARD makes a connection between Terminal 2 and Terminal 12 on the VFD terminal strip to run the motor FORWARD. The drum switch when switched to REVERSE makes a connection between Terminal 2 and Terminal 13A on the VFD termina strip to run the motor REVERSE.

There is a jumper between terminal 1 and terminal 2 which enables the fwd/rev start. IF I put in an E-stop it will break this connection for e-stop and make this connection if e-stop is released.

The drum switch controls the VFD (through it's terminal strip).............the VFD controls the motor.

I also noticed a high pitched whining from the motor when the system was running, I changed the parameter for carrier frequency from 6kHz to 4kHz and it only makes a whistle now when it is accel or decel the motor...otherwise it is very quiet.



Bill

[mactec54]

Hi willbird

Yes that was a good idea to use the switch that way most use the old machine switch
to turn the in coming power to the drive on & off but like you said anyone that has used a Bridgeport get used to the old way of using the switch you just have to have another switch for the in coming power to the drive

I'm not sure that you want to reverse the motor at speed with out a dump/Braking resistor you will most likley burn up the small one Built into the drive some drives will just go/drop out into overload & some will try to stop & reverse but it's built in braking resistor will not last very long when doing this

[Willbird]

Hi willbird

Yes that was a good idea to use the switch that way most use the old machine switch
to turn the in coming power to the drive on & off but like you said anyone that has used a Bridgeport get used to the old way of using the switch you just have to have another switch for the in coming power to the drive

I'm not sure that you want to reverse the motor at speed with out a dump/Braking resistor you will most likley burn up the small one Built into the drive some drives will just go/drop out into overload & some will try to stop & reverse but it's built in braking resistor will not last very long when doing this

Well the rate of decel can be adjusted by parameter, and the drive is really doing no more work to decel, and reverse than it is to just decel and STOP is it ?? Plus remember this is a FIVE hp vfd that does not require derating to run single phase, running a 2hp motor.

I do not do a whole lot of power tapping anyway....really I should look for a tapmatic I suppose.

Bill

[mactec54]

Hi willbird

Yes if you have the decel set correctly this will slow the motor untill it changes direction & will save the braking resistor from burning up but this is sure not good for taping its ok for through taped holes if you have the room for the tap to wind down until the motor can change direction

If your VFD is 3 phase rated input & running on single phase it has a derating of 50/60% there is no way around that even if it was for 5hp & only runing a 2 hp motor

Now if your drive which you have not said is rated 230v single phase input (& can not have 3Phase input at all ) then there is no derating of the drive as you will see the input amp rating is almost double on the single phase drive as it is on the 3phase drive this is one of the reasions for the drives to be derated the input amp draw

[Willbird]

Hi willbird

Yes if you have the decel set correctly this will slow the motor untill it changes direction & will save the braking resistor from burning up but this is sure not good for taping its ok for through taped holes if you have the room for the tap to wind down until the motor can change direction

If your VFD is 3 phase rated input & running on single phase it has a derating of 50/60% there is no way around that even if it was for 5hp & only runing a 2 hp motor

Now if your drive which you have not said is rated 230v single phase input (& can not have 3Phase input at all ) then there is no derating of the drive as you will see the input amp rating is almost double on the single phase drive as it is on the 3phase drive this is one of the reasions for the drives to be derated the input amp draw

My drive is rated for 5hp on 220 single phase or 3 phase, NO derating required for single phase input. Some older drives require derating, this drive does not, and is specifically designed to provide full 5hp output when running 230 single phase input.

Even plugging a 3 phase motor does not give INSTANT reverse on full 3 phase, there is still a decel/accel cycle going on.

Input amperage for 230 single phase is 29 / 26 amps, for three phase input amperage is 19.6 / 17.1 .

Bill

[mactec54]

Hi willbird

For stopping without any ramp up ramp down It is called dynamic braking & all VFD drives can do this with the added option that is available for them it is the braking resistor module no ramp up or down needed with this instant stop & instant foward & reverse also

You did say that your fan runs all the time you can change this with a parameter to only run when the motor is running

What is the drive brand name & model number as others might want to buy this drive as well

[Willbird]

Mine is an AC tech 250Y

It has a built in braking resistor, and an overheat detector for said resister.

There is some info in the manual about setting a timer for the drive to "go to sleep"....I'm not sure if that will shut the fan down or not, I am not seeing a parameter for when the cooling fan runs.

Bill

[Al_The_Man]

Dynamic braking usually comes into play automatically if the DC supply rises due to a high voltage caused by motor regeneration, e.g. fast decel.
When a high voltage is sensed a the braking resister starts be switched in, in order to absorb the high voltage.
Some drives also will have a DC injection braking feature, which injects DC into the motor winding for electronic braking.
Bill, Check to see if your drive has a standby mode, this feature allows the logic to be powered and the main DC switched in when needed, this does not run the fan until the DC power is up.
This may be the sleep mode you mentioned.
Al.

[mactec54]

Hi willbird

The braking resistor that is built in is very limited as to how it works as you can use a small amount of DC injection for helping to ramp down a little faster thats when this resistor comes into play

If you check your drives options on the web site you will see the add on dynamic braking kit part # 845-213 this is what you need for Instant foward/rerverse & is great for taping & cheaper than a Tapmatic & better

It seems the drive does not have all the features as some other drives have & you may not be able to turn the fan to run when the drive runs only the sleep mode may work

[Willbird]

Hi willbird

The braking resistor that is built in is very limited as to how it works as you can use a small amount of DC injection for helping to ramp down a little faster thats when this resistor comes into play

If you check your drives options on the web site you will see the add on dynamic braking kit part # 845-213 this is what you need for Instant foward/rerverse & is great for taping & cheaper than a Tapmatic & better

It seems the drive does not have all the features as some other drives have & you may not be able to turn the fan to run when the drive runs only the sleep mode may work

There was a rev number stated in the instructions for the external DC brake manual, it is on the heat sink, I have not yet looked at my drive to see if it is past that rev number.

I read over both the man for the drive and the man for the ext dc brake and it makes sense how it gets wired up....it costs $112 from the supplier I got the drive from. I have to look at the params again to be sure I am even using DC braking right now, in back gear the machine does halt in about 1 rev from when you give it a "stop" command...but in back gear that may be several MOTOR revolutions. it is possible I just have a very fast ramp down speed set in the parameters and it is not dc braking at all.

Edit >>> I had a look at parameters today and I have it set to decel then brake.

Bill

[mactec54]

Hi willbird

I forgot about you having a back gear which you are probably using for your tapping
you would not need the Dynamic braking when using the backgear for tapping as the machine will slow enough to reverse with alittle ajustment on your drives DC braking
that would do it

But if you want to do the tapping with not using the back gear for more speed then you will need the Dynamic braking kit

[Willbird]

I think eventually I may add the dynamic braking module anyway.....

Just pondering if I need the 5hp dynamic brake module for my application or if the 2hp one would work.

I pretty much decided if I need a 5hp vfd for something that I will just buy a 2hp vfd for the mill and then use the 5hp for whatever need arose.

The 2hp dynamic braking module is $116 vs $150 for the 5hp one.

Bill

[Al_The_Man]

The difference in the 2hp and the 5hp is the resistor value.
I think you will probably get away with the 2hp model for a 2hp motor. The regeneration energy is has to dissipate is going to originate from a 2hp motor!
Models that already have a limited one built in, is OK up to a certain decel value, for rapid & frequent decel's, the external is needed.
Al.

[Willbird]

The difference in the 2hp and the 5hp is the resistor value.
I think you will probably get away with the 2hp model for a 2hp motor. The regeneration energy is has to dissipate is going to originate from a 2hp motor!
Models that already have a limited one built in, is OK up to a certain decel value, for rapid & frequent decel's, the external is needed.
Al.

Yeah Al, my thinking was that if I replaced the VFD with a 2hp model the resistor would stay with the mill.

Bill