Massoth 4 Channel Switch Decoder 8156001 - Lighting

[electricity_bill]

Hello

I am trying to use my Massoth DiMAX 4 Channel switch decoder 8156001 to operate some flashing lights on a level crossing. I need it to flash two LEDS symmetrically alternately. I have the LEDS connected to F3 and F4 and the +ve terminal but I cannot get it to work. Nothing else is connected. Could anyone give me some help on the CV settings?
Bill

 

[Greg Elmassian]

you might want to start with the settings you already applied.

Greg

 

[PhilP]

Have you got suitable current-limiting resistors in series with your LED's?

 

[electricity_bill]

Have you got suitable current-limiting resistors in series with your LED's?

Yes I have.

 

[muns]

Do you have it configured as a Switch Decoder (CV29=128/bit 7 on default) or a Loco decoder?

CV53 & 53 control F3 & F4 - Set CV53 between 1 & 15 to set the symmetric flash duration. Set CV54 to 16 (inverse with F3)

 

[electricity_bill]

Do you have it configured as a Switch Decoder (CV29=128/bit 7 on default) or a Loco decoder?

CV53 & 53 control F3 & F4 - Set CV53 between 1 & 15 to set the symmetric flash duration. Set CV54 to 16 (inverse with F3)

Mark,

Do you have it configured as a Switch Decoder (CV29=128/bit 7 on default) or a Loco decoder?

CV53 & 53 control F3 & F4 - Set CV53 between 1 & 15 to set the symmetric flash duration. Set CV54 to 16 (inverse with F3)

Mark

Thanks for that and I have just got around to trying out your suggestions and I have made it work. My only query is that the alternating voltage appears across F3 and F4 (21V) and not between either of them and the + terminal as shown in the manual. Any ideas ?
Bill

 

[Greg Elmassian]

Are you asking why when measuring with a voltmeter between F3 and F4 you see an alternating (I assume voltage that changes polarity) voltage?

Of course you do, since you have F3 and F4 being alternately pulled to ground, and there's probably a bit of "pull up" voltage when they are not "on"..

F3 and F4, like all decoders are "pulled to ground" when active... so when F3 is "on" it is pulled to ground, and F4 "floats high" because it is not on, and with only the current flow of the meter, F4 can look "high", i.e. show the voltage from your common, which is positive.

Does this help?

Greg

 

[electricity_bill]

Are you asking why when measuring with a voltmeter between F3 and F4 you see an alternating (I assume voltage that changes polarity) voltage?

Of course you do, since you have F3 and F4 being alternately pulled to ground, and there's probably a bit of "pull up" voltage when they are not "on"..

F3 and F4, like all decoders are "pulled to ground" when active... so when F3 is "on" it is pulled to ground, and F4 "floats high" because it is not on, and with only the current flow of the meter, F4 can look "high", i.e. show the voltage from your common, which is positive.

Does this help?

Greg

Greg
I think I understand and will have another play later today. One other issue, I want to use the lighting button (bottom left No9 ) on my Navigator to turn the lights on and off. Currently I use button 1 having made CV 41 = 1. If I change it to 0, as the manual seems to suggest, it does not work. Any ideas?

Bill

 

[muns]

CV41 to 49 are only valid when the unit is acting as a "Loco decoder" and not a "Switch decoder". How do you have it configured?

 

[electricity_bill]

CV41 to 49 are only valid when the unit is acting as a "Loco decoder" and not a "Switch decoder". How do you have it configured?

As a loco decoder address 100.

 

[Greg Elmassian]

short address 100 or long address 100?

makes a difference..

 

[muns]

Well if you want F3/F4 to operate using the light key then you need to set CV43 & possibly 44 to 0

CV41 determines what key operates F1 (default 1)
CV42 determines what key operates F2 (default 2)
CV43 determines what key operates F3 (default 3)
CV44 determines what key operates F4 (default 4)

 

[electricity_bill]

short address 100 or long address 100?

makes a difference..

It is the short address CV1

 

[Greg Elmassian]

My idea was does your system discriminate/allow both long and short addresses at 100? I have seen systems that assume any number over 99 is a long address, i.e. no way to use short address 100 (even though service mode will allow CV1 to be set to 100)

Just conjecturing.

Greg