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Current value display
I use the inverter as the load of the pump.
When I change the frequency from 42 Hz to 50 Hz, display of the output side current value changes from "30 A" for 42 Hz and "30 A" for 50 Hz. However, the current value does not change.
I measured the output side current value using a clamp meter.
Let me know how to find the cause.
When I change the frequency from 42 Hz to 50 Hz, display of the output side current value changes from "30 A" for 42 Hz and "30 A" for 50 Hz. However, the current value does not change.
I measured the output side current value using a clamp meter.
Let me know how to find the cause.
- Category :
Answer
The motor-generated torque elements have the following relationship:
Torque T = K I V/F
K: Constant
I: Current
V: Voltage
F: Frequency
The inverter regularly performs control (V/F control) with the output voltage and output frequency kept constant.
From the above equation, if V and F are constant, the torque T proportionates to the current I.
If the current value remains the same for 42 Hz and 50 Hz, it is considered that the load does not change.
Since the load of a capacitive pump does not change when the frequency changes, such a case can occur.
Torque T = K I V/F
K: Constant
I: Current
V: Voltage
F: Frequency
The inverter regularly performs control (V/F control) with the output voltage and output frequency kept constant.
From the above equation, if V and F are constant, the torque T proportionates to the current I.
If the current value remains the same for 42 Hz and 50 Hz, it is considered that the load does not change.
Since the load of a capacitive pump does not change when the frequency changes, such a case can occur.
- Product Name
- Inverter, magnet motor drive
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