[60 convert]

I recently purchased a used partner 1d, I was able to use it before buying it. now that its home I have used it some and today it seems every time I program a rpm it always goes to the same rpm even though the screen says its at the rpm I told it to go to. I don't have a tac but I do believe its going to the 1750 that the motor is? does anyone have an idea for where I should start to look to fix this? as well as buy a decent hand held tac to verify the rpm? Also the spindle doesn't always start when you command it to do so.

Jesse

[Brian L]

I'm chasing some rpm issues on my Partner 4.... there are a lot of possible issues. First I would check mechanical, are your belts tight? Then you have a VFD running the spindle, find out what brand and model and get/find an owners manual and decipher your settings on the VFD. Most likely the display on the VFD will show the frequency output. so figure your maximum speed, mine is 5000 rpm, and given the max frequency on your drive might be 190hz (that should be one of those settings I said to check), you can figure out roughly what frequency should jive with what rpm. So, 5000/190=26.3, that's 26.3 rpm per hz. so 10hz on the output of the VFD will change your rpm roughly 260 rpm.

You will also want to check the 0V-10V analog signal coming to the VFD, check our wiring diagram to find some terminals to hook your voltmeter to... they are on the main relay board left side on my machine.... If you have 5000rpm that you will roughly have 2V change per 1000rpm.

You will need a tach for all of this.... I found a nice digital tach from a friend of mine, but they are all over Ebay. Mine is a non-contact hand held laser that you use a small piece of reflective tape on the spindle to trigger it.

If the signal from the computer side is having issues, there are a couple chips that can be changed, see my post a few below this one.... didn't help so far on mine... but if you happen to need the same chips, I have extra's.

And another thought... if the machine was running correctly at the other place, did they have three phase and you are running single phase or trying to use a phase converter?

[sportybob]

The P1D has a "3 step" pulley,. Low, med, Hi. depending on the "belt position" and what the Called out spindle range is, you can end up not getting an accurate spindle out put.
The spindle "analog voltage" is tied to the "MISC" spindle parameters. these set up the spindle speed to the "low, med, hi" ranges. if you are set to Low range, it "locks" the spindle speed to that "max RPM. If the belts are in "high" range, and the spindle speed is set to "low" range. you will end up with a "different spindle speed". make sure the spindle range is set to the "belt" position.
Older machines had a single belt and 3 speed ranges(m low, med , high) . other machines use 2 belts ( matched sets) and have 2 spindle speed ranges. ( low, high)

Sportybob
PM me if you need more info.

[60 convert]

Thanks for the input I will check the 0-10 voltage as soon as I can find it in the manual and on the machine. the motor was working correctly as far as going to the correct rpm before. one other thing to note is that before this started sometimes when you turned the machine on and started the spindle it wouldn't do anything, the display would say you are at the commanded rpm but it would actually be idle?
Jesse