25 – 422 HEIDENHAIN Service Manual iTNC 530
25.4 Error Diagnosis on TT Touch Probes
Control impaired? If you suspect that a damaged touch probe or a touch probe into which liquid has penetrated
impairs the function of the control:
8 Disconnect the touch probe and observe the reaction. --> See “Deselecting and
Disconnecting the Touch Probe” on page 25 – 426.
Visual inspection
8 Visually inspect the touch probe and cable!
Are the touch probe or the cable damaged?
Checking the LEDs Two red LEDs (offset by 180°) on the TT 140 indicate that the stylus is deflected:
Checking the
"Ready" bridge
In the TT the Ready signal is bridged.
This means that the Ready signal must always be present if a TT probe is connected.
Proceed as follows to check the Ready bridge:
8 Shut down the control and switch off the machine.
8 Disconnect the keypad cable on connector X13 from the MC.
8 Use a multimeter which you set to "beep" mode or to ohm measurement.
8 Apply the needle tips to the pins 1 and 4 of the touch probe cable. --> A beep must be heard
or a low ohmic value displayed.
Assignment at the interface X13 (D-SUB, 9-pin, 2-row):
MC 42x(B)
Female Assignment X13 (TT)
1 Readiness
2 0 V (U
N
)
3 Do not assign
4+15 V ±5% (U
P
)
5 Do not assign
6 Do not assign
7 +5 V ±5% (U
P
)
8 Trigger signal
9 Trigger signal
––
Hsg. External shield
To Next Page
Loading...
