Nidec Embraco CF01F - Page 29

The frequency signal is a digital square wave and its parameters are described in Table 15.
Parameter
Level
OFF state
-5 V to +0,7 V
Indefinite state
+0,7 V to +4 V
ON state
+4 V to +15 V
Signals out of specification
below -5 V, above +15 V
Minimum duty cycle
30 %
Maximum duty cycle
70 %
Table 15 – Frequency signal specification
Once the range from +0.7 to +4 V is an indefinite state, one recommends avoiding it.
For frequency communication, the input resistance (R402) is 1,2 kΩ.
Figure 20 – Electrical schematics of CF01F and CF02F Inverters board configured as frequency
communication
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