Spindle speed not 100%

[AndyB]

1994 6030 10,000 rpm 15 hp

When I command 1000rpm for example and turn the spindle speed pot to 100%, the spindle is actually turning at about 600 rpm. It doesn't hit 1000 rpm until I turn the knob to about 175%, then the sceen displays the C axis is at 100%.

I've replaced the pot. The voltage accross the pot is 5V and when set to 100% the voltage at the centre white wire is 2.54 volts. I've verified this voltage to the spindle controller card. I think I have a spindle conntroller card problem, but I would like this verified before ordering a new part.

[Shizzlemah]

1) Turn on spindle and adjust speed pot until the screen displays 100%.
2) Loosen setscrew on speed knob
3) turn dial until the pointer aligns with "100%"
4) Tighten setscrew on speed knob

[AndyB]

Thanks for the reply, but if I just re-adjusted the knob, then my 0% would be near 200% and the highest I could go would be 125%, Do you follow.

100% should be half the travel of the pot.It's not. Half the travel of the pot only gives me about 60%. then if I continue to turn the knob the speed spindle will increase to 100% (knob shows 175%), then If I keep going the spindle speed will suddenly jump up to 200% (knob shows 200%).

As noted I've already replaced the pot and adjusted the knob.

[carbidecraters]

Wow thats weird!! Wish I had an answer for you

[HuFlungDung]

Perhaps the 5 volt control voltage is low, as in a weak power supply. On many VFD's the input voltage command would vary between 0 and 10 volts. Just my WAG.

[dango]

first we need to know the type of inverter to help
but you need to put in MDI S300M3M49
then you need to check on the inverter display that it 20HZ
if not you need to check and change the spindle speed parmeter in SETP
and if you change it then check M19 in both gear if it too fast
you have to decrease the orientation parameter

[AndyB]

/thanks for the input everyone.

Yesterday I swapped spindle controller cards from another machiine and the problem went away. With the spindle speed pot at 100 % the display on the screen showed 100% and the spindle turned at desired speed.

So this confirms I have a spindle controller card issue, or possibly an issure with the eproms on the card.