Fuji Electric Frenic Mini FRN001C1E-2U, Инструкция по эксплуатации

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2-16
Table 2.7 Continued
Classifi-
cation
Symbol Name Functions
- Since weak analog signals are handled, these signals are especially susceptible
to the external noise effects. Route the wiring as short as possible (within 65ft/20
m) and use shielded wires. In principle, ground the shielding layer of the shielded
wires; if effects of external inductive noises are considerable, connection to
terminal [11] may be effective. As shown in Figure 2.13, ground the single end of
the shield to enhance the shielding effect.
- Use a twin contact relay for weak signals if the relay is used in the control circuit.
Do not connect the relay's contact to terminal [11].
- When the inverter is connected to an external device outputting the analog
signal, a malfunction may be caused by electric noise generated by the inverter.
If this happens, according to the circumstances, connect a ferrite core (a toroidal
core or an equivalent) to the device outputting the analog signal and/or connect a
capacitor having the good cut-off characteristics for high frequency between
control signal wires as shown in Figure 2.14.
- Do not apply a voltage of +7.5 VDC or higher to terminal [C1]. Doing so could
damage the internal control circuit.
Analog i
nput
Figure 2.13 Connection of Shielded Wire Figure 2.14 Example of Electric Noise Prevention