Model Railway Forum

Go Back   Model Railway Forum > Model Railway Construction > General Modelling

General Modelling Use this area for modelling items that don't fit elsewhere


Reply
 
Thread Tools Display Modes
Old 12-03-2018, 01:19 PM   #1
Tankdave
Member
 

Join Date: Mar 2016
Location: Wilts
Posts: 73
Tankdave is on a distinguished road
Default Heljan Class 128 DPU

Just finished my sound installation consisting of a Zimo 644D & two Zimo speakers and whilst it sounds rather good, I cannot seem to eliminate the jerky medium & high speed running.

This jerkiness was not there on DC, and with the DCC sound turned off I can even hear the motor pitch changing along with the "bouncy" look to its progress.

Of course I have tried adjusting CV56 and have tried everything between 0 and 99.

I will confess that I don't fully understand the explanation of this in the Zimo manual.

Anyone have any idea's or encountered this?

Thanks in advance
Tankdave is offline   Reply With Quote
Old 12-03-2018, 05:24 PM   #2
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

Quote:
Originally Posted by Tankdave View Post
Just finished my sound installation consisting of a Zimo 644D & two Zimo speakers and whilst it sounds rather good, I cannot seem to eliminate the jerky medium & high speed running.

This jerkiness was not there on DC, and with the DCC sound turned off I can even hear the motor pitch changing along with the "bouncy" look to its progress.

Of course I have tried adjusting CV56 and have tried everything between 0 and 99.

I will confess that I don't fully understand the explanation of this in the Zimo manual.

Anyone have any idea's or encountered this?

Thanks in advance
Have you spoken to the company that you bought the decoder from?
I have fitted DCC sound to my Heljan 128 and have not had a problem (ESU not Zimo) so it may be a case of a faulty decoder.

However.........

Models are often fitted with suppressors to stop interference with radios and TV's. With out going into the technical reasons why, these suppressor's can cause the motor to 'hunt'.
If the model is fitted with suppressors they may need to be removed and this could well solve the problem.

Photos of suppressor's on a Bachmann 56xx......





I hope this helps and you can get every sorted.

John
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Old 12-03-2018, 05:32 PM   #3
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

Is it a LockSound V4? I am sure I read in the fitting instructions that they recommend removing the capacitors.
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Old 12-03-2018, 06:09 PM   #4
scratchbuilt
Senior Member
 

Join Date: May 2013
Posts: 261
scratchbuilt is on a distinguished road
Default

Also , turn off the BEMF CV setting , It will hunt because the feedback (Back EMF) is too high, If it cures it, turn it back on and fiddle with the BEMF CV setting for adjustment, contact your supplier if your still having problems .
scratchbuilt is offline   Reply With Quote
Old 12-03-2018, 06:36 PM   #5
Tankdave
Member
 

Join Date: Mar 2016
Location: Wilts
Posts: 73
Tankdave is on a distinguished road
Default

Its a Zimo decoder and does anyone know what the CV is to turn BEMF off is, only one I can see is CV56 and it has no mention of turning things off? and setting to "0" is actualy a setting of "55"

No suppression components on this model.

Last edited by Tankdave; 12-03-2018 at 07:47 PM.
Tankdave is offline   Reply With Quote
Old 12-03-2018, 07:27 PM   #6
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

http://www.zimo.at/web2010/documents...eDecoder_E.pdf

Page 12 says Back EMF is CV 56 so you may have already tried this.
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Old 12-03-2018, 07:29 PM   #7
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

I expect it is LockSound V4 you have on your Zimo decoder and it does suggest you remove the suppressors in the fitting instructions.

John.
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Old 12-03-2018, 07:42 PM   #8
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

http://www.southwestdigital.co.uk/PD...4_eBook_03.pdf

Page 18

6.8.4.1
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Old 13-03-2018, 01:30 PM   #9
Tankdave
Member
 

Join Date: Mar 2016
Location: Wilts
Posts: 73
Tankdave is on a distinguished road
Default

the Zimo decoder is made by Zimo, the Locksound V4 is a different make of decoder.

I did read in the Zimo manual that CV9 may help, it alters the EMF frequency, so I decided to have a "play"

It seems to have done the trick, medium & high speeds seem stable now "low speed was OK already" with it set to 87, I have left the CV56 set to "0" (which is 55)

Thanks for the tips though, I have more tests to do but it's looking better
Tankdave is offline   Reply With Quote
Old 13-03-2018, 03:39 PM   #10
Panniertank
Senior Member
 
Panniertank's Avatar
 

Join Date: Jul 2017
Location: Kidderminster
Posts: 548
Panniertank is on a distinguished road
Default

Quote:
Originally Posted by Tankdave View Post
the Zimo decoder is made by Zimo, the Locksound V4 is a different make of decoder.

I did read in the Zimo manual that CV9 may help, it alters the EMF frequency, so I decided to have a "play"

It seems to have done the trick, medium & high speeds seem stable now "low speed was OK already" with it set to 87, I have left the CV56 set to "0" (which is 55)

Thanks for the tips though, I have more tests to do but it's looking better
Glad you got it sorted.

Locksound is the ESU manufacturer.
__________________
Oh Doctor Beeching, what have you done?
Panniertank is offline   Reply With Quote
Reply

Bookmarks



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT +1. The time now is 04:53 PM.


Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.