Setting up an Encoder on the iS7 VFD

Setting up an Encoder on the iS7 VFD

This document serves as a supplement to the complete iS7 User Manual. It shows how to install and setup the iS7 VFD to utilize an encoder option board (P/N: 64110002). This option card supports line driver and open collector type encoders.

Card Installation

1.      Remove the front cover of the iS7 to expose the option slot highlighted below.

2.    The encoder option card is installed by lining the card up with the option connector and sliding to the right. Ensure that the pins are lined up properly; the card should slide in easily and fit flush with the plastic cover.

3.      Tighten the included screw to hold the card in place.
 


Wiring

Wire the motors encoder wires to the encoder card using the below reference table.

 

Terminal

Function

S

Shield connection

A+

Positive A channel pulse (A)

A-

Negative A channel pulse (/A)

B+

Positive B channel pulse (B)

B-

Negative B channel pulse (/B)

G

Ground connection, common for DC supplies below.

5V

5VDC supply to encoder

12V

12VDC supply to encoder

15V

15VDC supply to encoder

RTA/RTB

Return Pulse for channel A and B (open collector output)

 

The encoder card supports line driver type and open collector type encoders. Be sure to set the switch pictured below to the correct setting depending on the applied encoder. 

 

Parameter Setup

It is imperative to setup the below parameters and conduct an autotune to ensure proper operation of the iS7 with encoder feedback.

 

Parameter Code

Parameter Name

Recommended Setting

APO-01

Encoder Option Mode

1 – Feedback

APO-04

Encoder Type Selection

Set to line driver or open collector based on installed encoder

APO-05

Encoder Pulse Selection

Leave at A+B if using both channels

APO-06

Encoder Pulse #

Set to PPR of encoder

DRV-09

Control Mode

5 - Vector

DRV-14

Motor Capacity

Set to motor kW

BAS-11

Motor Poles

Set to # of motor poles

BAS-12

Rated Slip

Set to rated motor slip

BAS-13

Rated Current

Set to motor FLA

BAS-15

Rated Voltage

Set to rated motor voltage

BAS-20

Auto Tuning

1-All **This will rotate the motor, ensure motor is uncoupled from the load**

 

Troubleshooting

 Encoder direction error

If during the auto tuning process an encoder direction message is received...

  1. Is motor direction correct? Verify the motor direction is correct; FWD on keypad should match forward running for the application. If it is incorrect, swap the U and W motor wires and run the tune again. If the motor direction is correct set APO-05=- (A + B) and run the tune again.
  2. Parameter APO-08 will display the encoder’s frequency. While running FWD this should display a positive frequency close to the commanded reference. While running REV it will go negative. You can also turn the motor by hand while stopped and view the feedback.

 


Motor is not getting up to speed or is pulling high amperage

If the VFDs output speed is not matching the command reference or the motor is pulling high amps...
  1. Check the encoder wiring. If B+ and B- are swapped, for example, this symptom can occur. 
  2. ​Confirm that encoder PPR set in APO-06 matches the encoder’s nameplate.