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rustyovali
25th Apr 2018, 09:40 PM
I have recently acquired a Deckel FP1 and as part of the deal it came with a WEG 1440rpm 1.5kw 3ph motor and an AC Tech VFD.
Can I use the vfd to emulate the original 2 speed motor? Rather than having a pot to control speed I am hoping to use a 3 position switch {slow,off,fast} and 25hz and 50hz presets.Can this work? Will the motor loose torque at 720rpm?
Thanks in advance,Nick

BobL
25th Apr 2018, 10:05 PM
I have recently acquired a Deckel FP1 and as part of the deal it came with a WEG 1440rpm 1.5kw 3ph motor and an AC Tech VFD.
Can I use the vfd to emulate the original 2 speed motor? Rather than having a pot to control speed I am hoping to use a 3 position switch {slow,off,fast} and 25hz and 50hz presets.Can this work?
Yes that will be quite easy to do. The manual indicates that the TB2 terminals (13A, B and C) are used for up to 3 speed presets.


Will the motor loose torque at 720rpm?
Yes it will. At 25Hz it will have about half the torque.

You have several alternatives.

1) If possible investigate Using a lower gear ratio and run the motor at 50 and 100Hz instead, this will give you close to full power at both speeds

2) Upgrade the motor to 3kW but you will need a new VFD

3) I had a quick read of the manual for the ACTech SCF Drive and it does not appear to be a vector drive.
If you upgrade the VFD to a Vector drive VFD you will get between 2/3 and 3/4 the power at 25Hz and full power at 50Hz,

I strongly recommend attaching a pot because this allows you to work at slightly different speeds were there may be less vibe.

rustyovali
25th Apr 2018, 10:34 PM
Hi Bob thanks for the reply.


1) If possible investigate Using a lower gear ratio and run the motor at 50 and 100Hz instead, this will give you close to full power at both speeds
do you mean a lower motor pulley ratio or selecting a lower gearbox ratio?
Upgrading the vfd could be an option,any recommendations?

BobL
25th Apr 2018, 10:56 PM
Hi Bob thanks for the reply.
do you mean a lower motor pulley ratio or selecting a lower gearbox ratio?
Sorry I'm not familiar as to how they are setup.
I think its the first option as no doubt you still will want to use your gear ranges?


Upgrading the vfd could be an option,any recommendations?
I'm quite partial to the Powtran PI160s - you can read about them in this thread.
VFD install summaries - Page 10 (http://www.woodworkforums.com/f271/vfd-install-summaries-213878/10)

WCD
28th Apr 2018, 12:56 AM
.........
do you mean a lower motor pulley ratio or selecting a lower gearbox ratio?
Upgrading the vfd could be an option,any recommendations?

My FP1 came with a 1400/2800 rpm motor, so with a 240V 1400rpm motor I get the original spindle speeds with the VFD delivering 50/100Hz, and approx full motor power.

Some FP1s like yours came with 700/1400 rpm motors; if your FP1 is like that, the new 240V motor would double the spindle speeds if driven at 50/100Hz (to achieve full motor power). You can easily fix the speed problem by fitting a motor pulley half the diameter of the original.

The FP1 has a good range of speeds through the gearbox, so even a basic VFD would allow for modest speed variation to tune out chatter, and if you wanted to halve the lowest speed by running at 25Hz, there is so much torque available through the low gear ratio that halving the motor power should not cause a problem.

Cheers,
Bill

rustyovali
28th Apr 2018, 01:47 PM
Thanks Bill,I tried out the motor running at 1400 +700 rpm this morning by hooking it up temporarily to the VFD running my shaper.Seemed to work perfectly.Discovered some issues with the table feed so will start another thread

Cheers Nick