HNC Electric HBU Series, Руководство пользователя

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HBU Series Braking Unit
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5.2 Model selection of periodical braking load
As for load of periodical braking, using following ways
choose suitable braking units.
5.2.1
Confirm system’s peak braking current Imax
Peak braking current should be brake current which make
sure system work properly and load get enough braking torque.
(1) Normally, for 380V speed regulating system, when
braking torque need 100% rated torque during braking,
maximum braking current can be calculated as below:
Imax ≈Motor power (kW)
(2) After correctly choosing braking resistor, the current
can be approximately calculated out through below
formulation:
Imax ≈ 700/ brake resistor (Ω)
(3) Because great inertia load requires emergence braking,
it needs braking torque more than 100%, under this situation
bigger peak braking current is needed.
5.2.2 Confirm the average braking current Iav
(1) First confirm brake frequentness Kc of system, Kc is
defined as proportion of system braking time to total braking
period.
Kc = Brake continuing time/Brake period×100%
There is different braking frequentness KC for different
load type, so please confirm Kc according to actual running
status of speed regulating device. When running status of
actual load can not be confirmed, please refer to bellowing
experience value to confirm Kc. Normal braking frequentness