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Entry type: FAQ, Entry ID: 58276716, Entry date: 03/15/2012

3TK2810-1 Overspeed Monitors: Switching levels for the Low-High detection of TTL-HTL signals

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Where are the switching levels of the 3TK2810-1 overspeed monitor for the Low-High detection of TTL-HTL signals?




On the 3TK2810-1 overspeed monitor, the switching level for Low-High detection depends on the height of the control supply voltage of the encoder (i.e. 5 V or 24 V) by the use of TTL-HTL encoders.
The switching threshold is approximately 2.5 V and similar for TTL and HTL signals. A hysteresis was consciously renounced because the 3TK2810-1 overspeed monitor usually functions with all Sin/Cos, TTL and HTL encoders (without possible special versions).
The EMV measurements have shown that the device nevertheless works very robustly and reliably. The difference between TTL and HTL in the 3TK2810-1 overspeed monitor  merely lies in the analysis of wire breakage.


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