marklin-users.net community | Forum

 
Welcome to the forum   
Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error
Marklin 7286 turntable voltage problem
Share
Options
View
Go to last post in this topic Go to first unread post in this topic
Previous Topic Next Topic
Offline Dirtboy  
#1 Posted : 26 January 2025 00:23:25(UTC)
Retweet
Dirtboy

United States   
Joined: 01/12/2014(UTC)
Posts: 46
Location: Dallas, TX
I think I may have fried my turntable.

I've only had my 7286 turntable running analog for about 5 months. I've been using a 16v AC adapter I bought off of Amazon. It's been working fine until yesterday. Then it started buzzing like the solenoid was not getting enough power. I took the controller apart to see if any contacts were bad. Then I grabbed a voltmeter to check to see if I was getting proper voltage. I was pissed to find out the AC adapter that's labeled as 16v was actually putting out 19v!

Does anyone have an idea of which electronic component would die first due to over voltage?
Back to top

Wish to join the discussion?! Login to your marklin-users.net community | Forum accountor Register a new forum account. Or Connect via Facebook  
Back to top  
Offline JohnjeanB  
#2 Posted : 26 January 2025 10:08:34(UTC)
Retweet
JohnjeanB

France   
Joined: 04/02/2011(UTC)
Posts: 3,553
Location: Paris, France
Hi
Basically the 7286 TT has a 12 VDC motor (with a resistor in series, a coil and a few diodes.
If you have removed the bridge from the pitt it is easy to check the motor (smell and burnt aspect) and try connecting 10 VDC on it to see if it runs.
The soleinoid seems harder to burn while the motor hates to be locked
The solenoid commands a contact that will start the motor. There may be an issue with the contact
Here are some information regarding the TT
Traduction 7286.pdf (2,317kb) downloaded 29 time(s).
Cheers
Jean
My layout videos
latest vid
marshalling yard
My Layout
Back to top
thanks 1 user liked this useful post by JohnjeanB
Offline Goofy  
#3 Posted : 26 January 2025 10:46:20(UTC)
Retweet
Goofy


Joined: 12/08/2006(UTC)
Posts: 9,273
Originally Posted by: JohnjeanB Go to Quoted Post
Hi
Basically the 7286 TT has a 12 VDC motor (with a resistor in series, a coil and a few diodes.
If you have removed the bridge from the pitt it is easy to check the motor (smell and burnt aspect) and try connecting 10 VDC on it to see if it runs.
The soleinoid seems harder to burn while the motor hates to be locked
Cheers
Jean


Basically should motor shuts down if resistor and diodes are broken off.
I use Tortoise motor by connect half-wave in conjunction with two diodes.
With more safety way i use 12Vdc by cross wired DPDT switches.
I have not tested 7286 with (on)-off-(on) two pole switch by cross wire with 12Vdc, but in this case you must remove resistor and diodes under the bridge/turntable.

H0
DCC = Digital Command Control
Back to top
Offline Dirtboy  
#4 Posted : 26 January 2025 17:58:16(UTC)
Retweet
Dirtboy

United States   
Joined: 01/12/2014(UTC)
Posts: 46
Location: Dallas, TX
Problem solved.

First off, thank you for the helpful replies.

After removing the bridge a second time to check the motor, I noticed the yellow wire going to the motor assembly had come de-soldered. I quickly re-soldered the connection and tested the motor and all works fine.

Now I'm just waiting for a proper 16v AC power supply to arrive from Amazon. This time I will check it first with a voltmeter.
Back to top
Offline JohnjeanB  
#5 Posted : 26 January 2025 21:10:20(UTC)
Retweet
JohnjeanB

France   
Joined: 04/02/2011(UTC)
Posts: 3,553
Location: Paris, France
Märklin made an adjustment on the Fleischmann TT They changed the resistor in series (increased the value compared with the Fleichmann version made for 14 VAC .
Not so much because of motor damage but rather because of "Ballistic overshoot". If the TT goes too fast there is a risk to block the latching pin which will cause additional wear and tear.
But you are right better use the proper PSU.
Cheers
Jean
My layout videos
latest vid
marshalling yard
My Layout
Back to top
Offline kiwiAlan  
#6 Posted : 27 January 2025 22:17:44(UTC)
Retweet
kiwiAlan

United Kingdom   
Joined: 23/07/2014(UTC)
Posts: 8,458
Location: ENGLAND, Didcot
Originally Posted by: Dirtboy Go to Quoted Post
Problem solved.

First off, thank you for the helpful replies.

After removing the bridge a second time to check the motor, I noticed the yellow wire going to the motor assembly had come de-soldered. I quickly re-soldered the connection and tested the motor and all works fine.

Now I'm just waiting for a proper 16v AC power supply to arrive from Amazon. This time I will check it first with a voltmeter.


Any form of AC transformer will show more than 16VAC under no load, and will probably show more than its rated voltage up to around half rated load. I don't think being a little over voltage is causing your problems.
Back to top
thanks 1 user liked this useful post by kiwiAlan
Users browsing this topic
Guest
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

| Powered by YAF.NET | YAF.NET © 2003-2025, Yet Another Forum.NET
This page was generated in 0.427 seconds.