ABB ACS880 Firmware Manual page 95

The cable drum turns one revolution per 50 revolutions of the motor shaft.
• parameter 90.61 Gear numerator
• parameter 90.62 Gear denominator
(These parameters need not be changed as position estimate is not being used
for feedback.)
• parameter 90.63 Feed constant numerator
• parameter 90.64 Feed constant denominator
The load moves 70 centimeters, i.e. 7/10 of a meter, per one revolution of the
cable drum.
The load height in meters can be read from
90.03 Load speed
Example 2: Using two encoders
One encoder (encoder 1) is used for motor feedback. The encoder is connected to
the motor shaft through a gear. Another encoder (encoder 2) measures the line
speed elsewhere in the machine. Each encoder is configured as shown in
Configuration of HTL encoder motor feedback
settings are made:
• parameter 90.41 Motor feedback selection
• parameter 90.43 Motor gear numerator
• parameter 90.44 Motor gear denominator
The encoder turns three revolutions per one revolution of the motor shaft.
• parameter 90.51 Load feedback selection
The line speed measured by encoder 2 can be read from
value is given in rpm which can be converted into another unit by using
gear numerator and
cannot be used in this conversion because it does not affect
Example 3: ACS 600 / ACS800 compatibility
With ACS 600 and ACS800 drives, both the rising and falling edges from encoder
channels A and B are typically counted to achieve best possible accuracy. Thus the
received pulse number per revolution equals four times the nominal pulse number of
the encoder.
In this example, an HTL-type 2048-pulse encoder is fitted directly on the motor shaft.
The desired initial position to correspond the proximity switch is 66770.
displays the rotational speed of the cable drum.
90.54 Load gear
Standard program features 95
= 1
= 1
= 7
= 10
90.07 Load position scaled
above. In addition, the following
= Encoder 1
= 1
= 3
= Encoder 2
denominator. Note that the feed constant gear
int, while
90.03 Load speed. This
90.53 Load
90.03 Load speed.