HEIDENHAIN NPD 281 v.3 User Manual
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RS-232-C/V.24 Interface (X31)
baud rate
Measured value output after signal through the “Contact”
or “Pulse” inputs
To start measured value output through the EXT interface
(X41) you can either:
➤
➤
➤
➤
➤ Close the “Contact” input (pin 23 on X41) against 0 V,
for example with a simple switch (make contact);
or
➤
➤
➤
➤
➤ Close the “Pulse” input (pin 22 on X41) against 0 V,
for example by triggering the input with a TTL logic
device (such as SN74LSxx).
Characteristic times for measured value output
Process
Time
Minimum duration of “Contact” signal
t
e
≥
7 ms
Minimum duration of “Pulse” signal
t
e
≥
1.5 µs
Storage delay after “Contact”
t
1
≤
5 ms
Storage delay after “Pulse”
t
1
≤
1 µs
Measured value output after
t
2
≤
57 ms
Regeneration time
t
3
≥
0
The time for measured value output (t
2
) is the
longest during a DIFF series of measurements.
Duration of measured value transfer
t
D
=
[s]
Triggering the “Contact” and “Pulse” inputs at D-sub connection
EXT (X41)
Signal transit times for measured value output after “Pulse” or “Contact”
Pin 1(0V)
Pin 23
Pin 22
Pin 1(0V)
EXT(X41)
EXT(X41)
t
1
t
2
t
e
t
e
t
D
t
3
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