HEIDENHAIN TNC 306 Technical Manual - Manual (Page 173)

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TNC 406/TNC 306 5 EMERGENCY STOP routine 4-73
5.2 Flow diagram
The external electronics must meet the specified conditions. In particular, the acknowledgment for
"Control operational" must reach the TNC after a maximum of 146 ms.
X21/34
X41/34
X22/4
X42/4
1 2 3 4 5 6 7 8 9
VDU-display
1. Wait for control voltage. EXTERNAL DC VOLTAGE MISSING
2. Recognize the control voltage on X22/4 or X42/4 and
reset the "Control operational" output on X21/34 or
X41/34 (t < 70 ms).
3. Maximum time during which the "Control operational"
on X22/4 or X42/4 must go to 0 (t < 146 ms). If
exceeded, EMERGENCY STOP DEFECTIVE
4. Recognize the acknowledgment and set output X21/34
or X41/34 (t < 24 ms).
5. Wait for control voltage. EXTERNAL DC VOLTAGE MISSING
6. Normal control operation. Output and acknowledgment
"Control operational" are high.
7. Control voltage switched off externally. External EMERGENCY STOP
8. After the control voltage is switched on again, the error
message can be canceled, followed by normal control
operations.
9. The control switches off the output "control operational"
(X21/34 or X41/34 ) after recognizing a fault. Flashing Error Message