Need Help!- heidenhain TNC 425 trouble need Help

[giardbusa]

I think of my heidenhain TNC 425 doesn't send signal to visual display Unit and I don't know how test the video board or X43 plug.
Habitually wen I open the power switch on of my milling the video display open automatically and the motor lubricate slide for 20 second. But today no oil and no video I have power 24 volt to the TNC but noting work




Tank You.

[cncserveng]

I dont think your NC control is coming on, the lub pump will be controlled by the PLC after the NC boots up.

You need to check the power to the NC and the NC on button is working correctly (after you have checked 3 phases mains to the machine.)

[giardbusa]

All the led on power supply of NC are open
I make test point on power supply board of NC
LH 22 and LH24 +5V
LH 20 and LH24 +12V
LH 28 and LH24 +15V
LH 24 and LH24 -15V Here I test 5 volt probably it is my problem?[/COLOR]Look attachement for this point.
LH 10 and LH24 +Ubatt
LH 1 and LH24 +5V



I tink I suppose to have power on PLC output X41 pole for emergency stop and I don’t have voltage from this wire.

I don't know which other test to do.

[cncserveng]

I'm sorry but all my experience and training is from the LE426,430 and i530 so my information may not be correct for your control.

Usually (on the 426), you need more than one 24v input to the NC, on X44.1;X44.2 and X44.3. The .2 and .3 inputs come if there is not an external emergency stop.

If the NC is ready, there will be a 24v ready signal from X34.1 to X41/34. This 24v output will hold in a relay usually labelled K1 and this is in the emergency stop chain, must be OK before you can put on the control.

I suspect maybe you have a defective external emergency stop button somewhere, maybe the one you normally pull out has broken off behind the panel. Or something like that.

[giardbusa]

TNC 426 is very similar than mine exept hard disk (Under reserve)
Ok good you follow me.

Where is the X34.1?

Tank You

[giardbusa]

On TNC 425 I have + 24 volt at connector X 31
I have + 24 volt at connector X 44 pole 2
I don’t have + 24 volt at connector X 44 pole 3

After switching the machine (ON) it is normal of don’t have + 24 volt at connector X 44 pole 3?

If I push manually on relay K5 I found + 24 volt at connector X 44 pole 3 of TNC

I think the relay -K5 is activate by relay -K55 and the relay -K55 is activate by the interface x31 pole 25 TNC PLC output X41 pole 34

I don’t have voltage at PLC output X41 pole 34 and by consequent interface X31 pole25

[giardbusa]

I have 28 volt on pole L+ of K1 Safety contactor emergency stop and the green lower light come on after put the main switch at ON position and my video display don't open automatically (vidéo display not receive data from computer)

If I push on button S6 of the key board the coil of relay -K4 come ON, The upper light green of K1 come ON, after releasing button S6 the coil of relay -K4 come OFF and The upper light green still open and it give 28 volt to the pole14 of K1 unit.

If booth green Light come ON on K1 Unit emergency stop, emergency stop chain is OK or I need look some other tings ?

[giardbusa]

With voltage one X31 and X44 pole2 except pole 1. And I unplug all Connection on the PLC except X43 for screen. The Screen suppose to come ON after pout main switch ON??

I made this experience and my screen still OFF

[giardbusa]

When this Green light suppose to come ON? Look in attachement.
Tank You Yves Giard

[cncserveng]

If you follow the ready signal around the safety chain circuit you will see it comes back the the NC off / on button. If this circuit remains open the screen will not come on. It could be an external safety or bad contact after the K1 safety relay.

on the LE426 X34.1 is a 24v connector with 24v from the emergency curcuit, the same 24v needed for the NC on button.

Please check the safety chain start preconditions from the K1 relay back to the NC on/off button.

This chain can go also thro' the spindle and axis drives ready relays.