TOYODenki VFDB2009 Series, Operation Manual

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33
Braking resistor:15[
Ω
](200
～
400[W]) 2 pieces
※
Braking resistor should select the small value of a inductance.
6.3 Selection of thermal relay
Thermal relay is a detector which DB unit becomes loss of control and prevents overheating of a braking
resistor, and is made to trip MCCB (or MC) of an inverter power supply.
Select the operating time of Thermal relay so that the state more than the maximum braking power operates
in 30 to 60 seconds. Keep in mind that it becomes a cause of a fire when the thermal relay does not operate.
Moreover, a thermal relay should use what operates with D.C. current.
6.4 Example of peripheral equipment selection
Example of selection of DB unit and a braking resistor, and a thermal relay is shown in the following table.
Table 6.1 Example of selection
Inverter
power source
voltage
Brake resistor
Thermal relay
Maximum
braking power
[kW]
Peak current
[A]
DB unit type
Type Setting
value[A]
200V series
(
Starting
voltage of DB
operation
360V)
1.5
Ω
×5S
N20 form 13.0 17.3 48
VFDB2009-50
1.5
Ω
×5S 2P N60A form 26.0 34.6 96
VFDB2009-200
1.5
Ω
×5S 3P N60A form 39.0 51.9 144
1.5
Ω
×5S 4P
N60A form 50.0 69.2 192
400V series
(
Starting
voltage of DB
operation
720V)
3.3
Ω
×7S
N20 form 8.5 22.4 31
VFDB2009-50
3.3
Ω
×7S 2P
N60A form 17.0 44.8 62
VFDB2009-200
3.3
Ω
×7S 3P N60A form 25.0 67.2 94
3.3
Ω
×7S 4P N60A form 34.0 89.6 125
3.3
Ω
×7S 5P
N60A form 42.0 112.0 156
3.3
Ω
×7S 6P
N60A form 50.0 134.4 187
※
Combination exceeding 1.5 times of the inverter capacity to be used of the maximum braking power is
not made.
※
Since the resistor and thermal relay of Table 6.1 are the selection articles of our company, please ask in
the case of use.