# Endat Encoder Position error **URL:** \ **Category:** Mechatronics & Motion\ **Tags:** acopos-multi\ **Created:** [September 13, 2024, 11:34am UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308 "2024-09-13T11:34:57Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![harshagowda0707](https://avatars.discourse-cdn.com/v4/letter/h/FF8800/32.png) [@harshagowda0707](https://community.br-automation.com/u/harshagowda0707)\ **Post date:** [September 13, 2024, 11:34am UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/1 "2024-09-13T11:34:57Z")
Drive Used : **8BVI0055HWD0.000-1** Motor used : **8LSA46.DB030S100-3** (Compatible for Inductive EnDat encoders) Endat Encoder used : **8BAC0120.001-2** (Used with the single turn configuration ,no battery) For our application we have used the motor with the planetary gearbox with GR 1:24(24 motor revolution for 1 output revolution). The Axis is configured as periodic rotary with period 360 (MpAxisBasic Axis ).This axis is used as CNC axis With MpCnc4Axis Block. Homing procedure is used for axis homing (Since endat encoder is used in single turn mode position feed back is available). For a machine cycle motor is running for around 60 turns CW and 60 turns CCW. After running few machine cycles once the once the machine is powered off and again powered on the the position feedback of the encoder is changed (the position shift of the encoder is around 120 deg at the Output side).This issue occurs after powering off and then powering on the machine. Any clue is welcome. Thank you for your help. ![Encoder1](https://europe1.discourse-cdn.com/brcommunity/original/2X/1/1d3fbfeed02e77fd851bb25c53d7bd48821f90f9.png) ![Mot1](https://europe1.discourse-cdn.com/brcommunity/original/2X/2/23a3b7421c9cc95a252ff2e698d82aae1978e7d5.png) ---
**Author:** ![corne.geerts](https://avatars.discourse-cdn.com/v4/letter/c/FF8800/32.png) [@corne.geerts](https://community.br-automation.com/u/corne.geerts)\ **Post date:** [September 13, 2024, 2:10pm UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/2 "2024-09-13T14:10:53Z")
It is not clear what homing mode you have used. The **8LSA46.DB030S100-3** has a multiturn endat 2.2 encoder without the need for battery. Normally you would use homing mode mcHOMING\_ABSOLUTE\_CORRECTION or mcHOMING\_RESTORE\_POSITION, but for defining the offset or value of remanent variable, you will need another homing mode and procedure. ---
**Author:** ![harshagowda0707](https://avatars.discourse-cdn.com/v4/letter/h/FF8800/32.png) [@harshagowda0707](https://community.br-automation.com/u/harshagowda0707)\ **Post date:** [September 18, 2024, 5:54am UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/3 "2024-09-18T05:54:31Z")
Got the answer, since it is a multi turn encoder after exceeding the 4096 rotation once the drive is powered off and on the encoder is taking the overflow value. So we are getting the unexpected encoder value. ---
**Author:** ![christoph.hilchenbac](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/christoph.hilchenbac/32/423_2.png) [@christoph.hilchenbac](https://community.br-automation.com/u/christoph.hilchenbac)\ **Post date:** [September 18, 2024, 8:45am UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/4 "2024-09-18T08:45:13Z")
If the movement range of this axis is limited to 4096 revolutions and you use a gearbox of i=16 or i = 32, then mcHOMING\_ABSOLUTE\_CORRECTION should actually be able to correct this. ---
**Author:** ![harshagowda0707](https://avatars.discourse-cdn.com/v4/letter/h/FF8800/32.png) [@harshagowda0707](https://community.br-automation.com/u/harshagowda0707)\ **Post date:** [September 18, 2024, 10:51am UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/5 "2024-09-18T10:51:57Z")
we are using 1:24 GR and the our axis movement is exceeding 4096 revolution. So we are getting the encoder position shift. ---
**Author:** ![michael.bertsch](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/michael.bertsch/32/239_2.png) [@michael.bertsch](https://community.br-automation.com/u/michael.bertsch)\ **Post date:** [September 18, 2024, 1:08pm UTC](https://community.br-automation.com/t/endat-encoder-position-error/4308/6 "2024-09-18T13:08:32Z")
Here is the Decision Making Picture for Homing from AS-Help. ![image](https://europe1.discourse-cdn.com/brcommunity/original/2X/a/addf3ad05a2663374bc6287fb771b9df884be12f.png) Consider the limitations of “Restore Position” or change Hardware. Greetings Michael