[godzila]

Dear All,

Please help, mv junior mfg date 1985.
It has alarm when rotate 2000 rpm.
OT100 spindle alarm;
in spindle amplifier has 2 red led ON.
Load meter more than 100%

when rotate spindle manually , it very light, doesnt heavy to rotate.
temperature spindle also cool.

Please remedy
Thanks
Sam

Attachment 189652
Attachment 189654

[underthetire]

Pretty early mvjr, so not sure if it's a geared head, could be not shifting if it's a geared head, or a blown transistor module, or a tach feedback from the motor.

[godzila]

Thanks for your respons bro, this machine don't have shift gear at spindle site.

[underthetire]

Sounds like its possibly a double wound integral spindle then if no gear box. If that's the case, they switch right about 2k rpm for high range, so you probably have a bad high speed contactor for winding change. Unfortunately on those old contactors, you will have to change high and low as a set, since the new ones won't work on the old ones. Typically they are labeled KM100&101 and typically called a reversing contactor set, even though they aren't used for forward and reverse.

[godzila]

Please can you show me where is it (the contactor)?

[The Swede]

Can´t imagine the old machine has a double wound motor

[PBr]

No, it really does not have a motor w/double winding.
I had a same issue with the spindle on the same machine with fanuc spindle drive
As some1 pointed out, it can by almost anything from loose cable contact to blown transistor module.
I'd suggest to dismount the drive, check all contacts - also which connect the PCB's. Also there may be a problem with feedback signal coming from the motor, it is an magnetic one and it needs to be adjusted as the magnet wheel on the shaft gets weaker.
I ended up with replacing the spindle drive with a newer inverter and a small PLC which controls it.