Emheater EM12 Series, User Manual

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EM12 User’s Manual 2. Product Information
13
c) The damage caused by using the frequency inverter for abnormal functions;
d) The relevant service fee is calculated according to the manufacturer’s standard, if there is contract, then it
carries out subject to the contract.
2.9 Selection Guide of braking component
Table 2-5 is the recommended value of braking resistor, users can select the different resistance value and power
according to the actual situation,(but the resistance value must not be less than the recommended value in the table,
and the power can be bigger.) The selection of braking resistance need to be confirmed according to the power
that the motor generated in the practical application systems, and is relevant to the system inertia, deceleration
time, the energy of the potential energy load, needs customers to choose according to actual situation. The greater
the inertia the shorter deceleration time is needed and more frequently braking, so the braking resistor needs the
one with bigger power but smaller resistance value.
2.9.1 Selection of braking resistance value
When braking, almost all the renewable energy of motor is consumed on the braking resistor.
According to the formula: U * U/R = Pb
In the formula:
U --- The braking voltage when the system brake stably (different system is different, for the 380VAC system
generally take 700V)
R - Braking resistor
Pb – Power of braking
2.9.2 Selection power of braking resistor
In theory the power of braking resistor is consistent with the braking power, but it need to be taken into
consideration that the braking resistor power will derate to 70%.
According to the formula: 0.7*Pr=Pb*D
In this formula:
Pr----Power of resistor
D---- Braking proportion (the proportion that the regeneration process accounts for the whole process)
Elevator---- 20%~30%
Uncoiling and coiling machine---- 20%~30%
Centrifugal machine---- 50%~60%
Occasionally braking load---- 5%
Other machine generally-----10%
Table 2-5 EM12 Inverter braking components selection table
Model
Recommend power
of braking resistor
Recommend
resistance value of
braking resistor
Braking
unit
Remarks
Single phase 220V
EM12-G1-d75 80W
≥ 150Ω
Built-in as
standard
No special
instructions
EM12-G1-1d5 100W
≥ 100Ω
EM12-G1-2d2 100W
≥ 70Ω
Three phase 220V
EM12-G2-d75 150W
≥ 110Ω
Built-in as
standard
No special
instructions
EM12-G2-1d5 250W
≥ 100Ω