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Frequency conversion function – Hitachi SJ300 Series User Manual

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Chapter 2 – Explanation of Functions

Note: If before the encoder error, another error (e.g. over current) is detected, then the prior error

causes the trip event. Therefore the encoder error display may not be shown even if there is an

encoder error.

2.9 Frequency

Conversion

Function

Some users may find it more convenient to monitor and program speed dependent parameters in familiar

units of linear speed, such as feet per minute, meters per second, etc. The inverter has the capability of

displaying certain key parameters in terms of vertical linear speed units rather than in frequency units (Hz),

if so desired. The factory default setting is Hz (frequency).

This function is activated by setting parameter A074 to “01”, and inputting the vertical speed at maximum

frequency into parameter A075. This value is often referred to as the “contract speed” of the elevator. The

inverter does all the calculations to display the proper units.

Parameters that would be converted include Scaled Output Frequency Monitor (d007), Output Frequency

Setting (F001), Multi-speeds 1 – 7 (A020 – A027). Please refer to the parameter tables in

Chapter 3

to see

a complete listing of parameters that are affected by this function.

For example, if an elevator system has a contract speed of 250 feet/minute at the motor base frequency of

60 Hz, you would set parameter A075 to “250”, and A075 to “01.” Then all frequency dependent

parameters shown in the tables would be in units of feet/minute.

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