Fuji Electric FRENIC-MEGA, Инструкция по эксплуатации

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5-145
Selecting Feedback Terminals
For feedback control, determine the connection terminal according to the type of the sensor output.
• If the sensor is a current output type, use the current input terminal [C1] of the inverter.
• If the sensor is a voltage output type, use the voltage input terminal [12] of the inverter, or switch over the terminal [V2]
to the voltage input terminal and use it.
For details, refer to the descriptions of E61 through E63.
Application example: Process control (for air conditioners, fans and pumps)
The operating range for PID process control is internally controlled as 0% through 100%. For the given feedback input,
determine the operating range to be controlled by means of gain adjustment.
Example: When the output level of the external sensor is within the range of 1 to 5 V:
• Use terminal [12] since the connection terminal is for voltage input.
• Set the gain (C32 for analog input adjustment) at 200% in order to make the maximum value (5 V) of the external sensor's
output correspond to 100%. Note that the input specification for terminal [12] is 0 to 10 V corresponding to 0 to 100%;
thus, a gain factor of 200% (= 10 V
÷
5 V
×
100) should be specified. Note also that any bias setting does not apply to
feedback control.
Application examples: Dancer control (for winders)
Example 1. When the output level of the external sensor is
±
7 VDC:
• Use terminal [12] since the voltage input is of bipolar.
• When the external sensor's output is of bipolar, the inverter controls the speed within the range of
±
100%. To convert the
output
±
7 VDC to
±
100%, set the gain (C32 for analog input adjustment) at 143% as calculated below.
10 V
≈
143%
7 V