Heljan western keeps blowing decoders..

[40034_Nick]

I have a Heljan 00 Western that has now blown 3 ESU sound decoders. Anyone else encountered this?

 

Clearly i need to bin the thing and keep the body.. Or change the circuit board?  

Edited November 17, 2022 by 40034_Nick

[jamesed]

Have you got one or more than one speakers fitted?  If more than one are you sure they are correctly wired to match the impedance to the decoder output?   If your overall impendance is lower than the specified decoder output that could blow your decoder.

[08221]

Does the loco run Ok on conventional DC with no decoder  fitted?

[Trainshed Terry]

Heljan locos have a high starting current draw with a train can exceeding 1amp, so when I fit a dcc decoder to my models I insure that have a maxiumum of 2 amps. All my Heljan models are not sound fitted.

 

I hope that is of help.

 

Terry.

[spamcan61]

Another possibility would be momentary shorting between pick ups and motor connections, which is a sure way of frying decoders and wouldn't show on DC.

[40034_Nick]

1 hour ago, jamesed said:

Have you got one or more than one speakers fitted?  If more than one are you sure they are correctly wired to match the impedance to the decoder output?   If your overall impendance is lower than the specified decoder output that could blow your decoder.

 

Just one speaker.. 

[40034_Nick]

1 hour ago, 08221 said:

Does the loco run Ok on conventional DC with no decoder  fitted?

 

Yes it does... 

[WIMorrison]

Can I ask what you mean by 'blown a decoder'. Is the loco running, but the sound isn't working, or does the loco not run at all?

 

I also wonder if it isn't running at all, have you tried to read the decoder to see if it has reset back to defaults, i.e. CV1=3? If you can read the decoder, have you tried to reset it?

[jamesed]

7 hours ago, 40034_Nick said:

 

Just one speaker.. 

 

Which version of Loksound Decoder are you using?

 

Loksound v3.5 or older have a 100 ohm output so if you connect up an 8 ohm or 4 ohm speaker that will probably blow the amplifier circuit and may cause further damage which could render it completely useless.   

 

Newer Loksound decoders will drive anything between 4 and 32 ohms which should be fine unless you have a 100 ohm speaker installed. If this is the case then the speaker probably won't work but it shouldn't cause any damage. 

 

It's worth checking the decoder version and the speaker impedance.  If there's no label on the speaker, use a multimeter to read the resistance across the speaker terminals. The reading you get will be just a little bit lower than the rated impedance.  

[40034_Nick]

18 hours ago, jamesed said:

 

Which version of Loksound Decoder are you using?

 

Loksound v3.5 or older have a 100 ohm output so if you connect up an 8 ohm or 4 ohm speaker that will probably blow the amplifier circuit and may cause further damage which could render it completely useless.   

 

Newer Loksound decoders will drive anything between 4 and 32 ohms which should be fine unless you have a 100 ohm speaker installed. If this is the case then the speaker probably won't work but it shouldn't cause any damage. 

 

It's worth checking the decoder version and the speaker impedance.  If there's no label on the speaker, use a multimeter to read the resistance across the speaker terminals. The reading you get will be just a little bit lower than the rated impedance.  

 Its a V5 running a 4ohm

[jamesed]

2 hours ago, 40034_Nick said:

 Its a V5 running a 4ohm

That should be fine then so we can rule that out.  

[40034_Nick]

I have replaced the decoder for a Lokpilot and hopefully it wont blow but if it does not as expensive as a sound decoder. 

It will just have to be a none sound loco..