Rockwell Automation 1336E IMPACT Adjustable Frequency AC Drive User Manual V 1-4.XX - Manual (Page 123)

Setting Up the Input/Output 7-11
Configuring the Pulse Input The pulse input lets an external source provide the drive with a digital
reference or trim signal. Pulse input is a differential input with a
maximum frequency of 100kHz. The parameters available for pulse
input include:
By using the pulse input, you can have an external source provide the
drive with a digital reference or trim signal. This can be useful if you
have a system with multiple drives and you want encoder magnetic
pickup or a lead drive that provides a pulse to supply the reference for
any secondary drives, called follower drives. You could use this
reference to ensure that all drives run at the same speed or to ensure
that the speed of the follower drives is related to the speed of the
reference.
Basically, the drive performs the following functions:
1. Uses the values that you enter into Pulse In PPR and Pulse In
Scale to perform some calculations. Pulse In Scale can be any
value from 0.01 to 10.00.
2. Applies the Pulse In Offset value.
3. Places the result in Pulse In Value.
The drive can use the value placed in Pulse In Value to, for example,
control the speed of a second motor.
For example, you could have a system with two drives. The lead drive
has a 1024 PPR encoder with a base speed of 1750 rpm. For this
application, the second drive, or follower, uses the lead drive’s
encoder, but the application needs the follower to run at half the speed
of the lead drive.
Figure 7.7
Pulse Input Configuration
To set up the follower drive, you would need to:
1. Set Pulse In PPR (parameter 120) to 1024.
2. Set Pulse In Scale (parameter 121) to 0.50.
file: Interface/Comm
group: Digital Config
To: Use this parameter:
Set the number of pulses per one revolution
Pulse In PPR
(parameter 120)
Apply a scale to the external source
Pulse In Scale
(parameter 121)
Add or subtract a fixed amount to or from Pulse In Value
Pulse In Offset
(parameter 122)
View the pulse input value
Pulse In Value
(parameter 123)
Lead
Drive
29 123
120
121
122
Pulse In PPR
Pulse In Scale
Pulse In Offset
Pulse In Value
Speed
Ref 1