HEIDENHAIN TNC 306 Technical Manual - Manual (Page 48)

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TNC 416/TNC 406/TNC 306 Nominal value output / Gap signal input 3–33
6 Nominal v alue output / Gap signal input
Nominal value output
The HEIDENHAIN contouring controls regulate the position loop servo with a nominal value potential
of • 10 volts.
Maximum loading of the nominal value outputs: 2 mA
Maximum load capacitance: 2 nF
Gap signal input
The gap signal (voltage) is connected to analog input X8 of the logic unit. The gap signal voltage
must be between 0V and + 5V. The TNC uses the gap signal to calculate new nominal values for the
analog outputs. (For a detailed description, see "Gap control").
The following RC circuit is integrated in the logic unit at the analog input for filtering of surge pulses
and for storing the analog signal.
Pin 2 220ý
Pin 10
R
a
0 V
100 nF
LE
X8
Time constant:
T = 22 µs (220
Ω ⋅ 100 µF)
5T = 110 µs
Since the output impedance Ra of the driver stage affects the entire time constant, a low output
impedance is necessary (for example 33
Ω).