Hitachi E5 J100, wich brake resistor

Hi,

I have an E5 J100 frequency drive, wich braking resistor may I use ?

Well now! It's a bit hard to answer such an open question but here's some guidelines.

First, The maximum wattage that the resistor needs to be is equal to the drive output kva. Using the formula W=E^2 x R, solve for the resistance using the DC bus voltage for E. (find your DC bus voltage by multiplying the input AC voltage by 1.35). That gives you the wattage and resistance value for maximum braking.

Second, there is no particular reason why you would automatically need all of that braking capacity. Many applications only need a little braking, for example, 10% of motoring kva. In that case, proceed just as in the example above but use the lower kva value for W. Your resistor will be higher in ohmic value and lower in wattage rating in this case.

You will also need a "brake chopper" unless the drive already has one built in. This brake chopper will have a minimum resistance value or maximum current value which must not be violated. After doing the math above check the chopper limits and adjust if needed.