Massoth 8FS Servodecoder 22 volt maximum load: 100 mA

LGB333

LGB333

Active Member
I'm using two sets of LGB ball bearing wheels for track power to a Massoth 8FS DCC Servodecoder in an LGB caboose. I plan to use this unit to power and control the following components I will be installing in the caboose:
1. Two Massoth interior LED light strips;
2. Two Warm White LED bulbs for LGB Marker Lanterns DC/DCC;
3. One automatic uncoupler........haven't decided yet on Kadee, Phoenix or Massoth unit;
4. One TrainLi.com Proline PL-92101 Pulsed Smoke Unit.

Question #1. The 8FS Servodecoder has several connectors for 5 volt servos and Massoth automatic uncoupler. It also has two connectors for 22 volt DCC track power with the DEC + 22 v pin shared between them. These two connectors are limited to a maximum load of 100mA. I plan to attach both sets of LED lights (two interior strips and two rear marker lights) to the two 22 volt connectors. How do I determine whether this will overload the 100 mA limitation?

Question #2. I haven't ordered the smoke unit yet, so I don't know its current draw. But I assume most smoke units would overload the 22 volt DCC connectors' 100mA maximum load so I plan to wire it directly to track power. Am I correct in my assumption on the smoke unit's load draw or could it also be connected to the 8FS's 22 volt connectors?

Thanks for the help electronics experts!
 
Greg Elmassian

Greg Elmassian

Registered
8 Mar 2014
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since you are using the track voltage as a common, put as many LEDs in series as you can to keep the current down.

you can set the current draw of LEDs with the appropriate resistors. Cannot tell you how the Massoth LED strips are set up, but surely there are specifications that tell you current draw.

yes, the smoke unit will draw over 100 ma.

Looking at that unit, even though it says "pulsed smoke generator" I do believe that the 4 wires are to the fan and heater (2 wires each) and the control comes from the decoder.

You can pull about an amp through the heater and the fan is typically around 1/2 amp.

So, if I am right, you need to drive the heater and fan from appropriate outputs, the Zimo has the high current outputs to do this, I don't know if Massoth does... you need to verify how the proline works (if I am correct), and then if it's as I say, see if the massoth can directly drive the heater and fan...

Greg
 
LGB333

LGB333

Active Member
Greg - Thanks for your response. The Massoth specs for these LED light strips, two to a pack, state:
Power Supply: 0-24V DC, AC, or DCC;
Total Load Capacity: Max 130mA;
Function Output: Max. 100mA, dimmable.

So, the Massoth 8FS unit has multiple 5 Volt connections for servo use. There's one 22V DCC Function Output at A5 and A6 on a three pin connector, with the center pin being the DEC +22V with a Max Load of 100mA. So, if I wire the two Massoth LED light stripes I'm installing in the caboose in SERIES, will the 8FS decoder's 100mA load capacity accommodate them? Or, will wiring the two light strips in SERIES together generate 200mA thus an overload for the 8FS? I'm just now starting to use LEDs for large scale requirements so this is a learning process for me.
 
Greg Elmassian

Greg Elmassian

Registered
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Well, you don't have the minimum voltage for the LED strips, each one would be getting 11 volts in series, but still 130 ma, over the 100 ma load limit.

So sounds like too much current right off the bat. The specs are very poor, should specify the minimum voltage.

Sounds like you should not be using them to connect to the output of the decoder.

Did you notice that there is a version of the LED strips with their OWN decoder, that could be connected directly to the track pickups? Why not use those?

Greg
 
LGB333

LGB333

Active Member
Well, you don't have the minimum voltage for the LED strips, each one would be getting 11 volts in series, but still 130 ma, over the 100 ma load limit.

So sounds like too much current right off the bat. The specs are very poor, should specify the minimum voltage.

Sounds like you should not be using them to connect to the output of the decoder.

Did you notice that there is a version of the LED strips with their OWN decoder, that could be connected directly to the track pickups? Why not use those?

Greg
Greg - Actually, these Massoth LED light strips can also be connected directly to track power but we wanted to run them through a decoder to be able to turn on/off.......same with the caboose rear lanterns. I already had them in my supply inventory and the other Massoth strips with the decoder are more expensive too.

But we've solved the overall issue.......the 8FS unit just doesn't have the horsepower to handle all the features we're continuing to put into the caboose. So, there is room inside the same hidden compartment to install and use a Massoth eMotion XL function decoder that has plenty of capacity......all the connectors, the headlight, taillight, interior light, and A1 - A6 can each handle 600mA. And it can be configured for the Massoth automatic coupler and a Massoth smoke unit. He may also want me to add a sound decoder to the install.

After my customer and I reviewed and discussed all the components' specs for the caboose project, we realized using the 8FS small decoder as the control was like trying to pull a huge house trailer with a Volkswagen........not designed for it!
 
Greg Elmassian

Greg Elmassian

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I think you missed, there is a version of the light strips that have a DECODER in them, i.e. they can be turned on and off with no connection to anything but the track.

But it seems you already bought the non-decoder model and you have even more to control, so I agree the additional function decoder makes sense.

How are you enabling the ability to program them independently (loco and function decoder) or are you using them on different addresses?

Greg
 
LGB333

LGB333

Active Member
I think you missed, there is a version of the light strips that have a DECODER in them, i.e. they can be turned on and off with no connection to anything but the track.

But it seems you already bought the non-decoder model and you have even more to control, so I agree the additional function decoder makes sense.

How are you enabling the ability to program them independently (loco and function decoder) or are you using them on different addresses?

Greg
We're going to set up the LGB Uintah loco and each of the five LGB trains cars (2 flatbeds, 2 box, and one caboose) with different decoder addresses, so he can control them on a computer operated shuttle layout. He's found a software system he's going to use for the operation. The Uintah loco will have a pulsed smoker and auto couplers (either Phoenix or Massoth), and all the five train cars, will have separate decoder addresses for their auto couplers. The caboose will have the Massoth LED light strips, rear marker light LEDs, a Massoth smoker, auto coupler, and a sound decoder containing up to five sound files such as coupling noise......maybe sound units in some of the other train cars. He's going to build a moveable, modular shuttle layout representative of the Uintah Railway so it can be set it up at train shows, etc. He's located in the Denver CO area.
 
Greg Elmassian

Greg Elmassian

Registered
8 Mar 2014
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San Diego
www.elmassian.com
I think you misinterpreted my question:
"How are you enabling the ability to program them independently (loco and function decoder) or are you using them on different addresses? "

In just the loco, you are putting 2 decoders, in reference to these 2 decoders: How are you enabling the ability to program them independently (loco and function decoder) or are you using them on different addresses?

Greg