Enough Amps?

[woodyfox]

Hi,

 

I have a Gaugemaster DCC01 rated at 2.5amps. I want to run 4mm scale, sound fitted motors around a layout a circuit measuring around 19m (58ft) in length. I intend to used heavy duty bus wire and frequent droppers. The two circuits will have only 2 turnouts each. The maximum number of motors operating at any single time will be 2-3. 

 

I'm beginning to wonder if the amp rating at 2.5 will be enough to cope?

[Oldddudders]

Suck it and see. Adding a booster isn't difficult, but don't waste your money yet. If the models are modern, then motor demands are fairly low, and sound only adds so much. 

[Kingzance]

8 minutes ago, Oldddudders said:

Suck it and see. Adding a booster isn't difficult, but don't waste your money yet. If the models are modern, then motor demands are fairly low, and sound only adds so much. 

Ian's advice is very wise. First, you need to get your layout constructed, wired and tested for short circuits particularly across your turnouts as stock runs over them. Meanwhile, if you know the specific decoders fitted in your locos, you can check their designed power handling and add the numbers together to give you a fair idea. It may be a good idea to split the two circuits into two power districts so that a short on one will not affect the operation of the other. On my OO gauge layout I have used 24/0.2 wire for a series of power districts with DCCConcepts PSX circuit breakers and PSX-AR reverse switches. Wire sizes after these devices start at 24/0.2 and then reduced to 16/0.2 away from the centre points of each district and I have used 7/0.2 wire droppers soldered to every length of track. My 2A rated NCE PowerCab successfully runs two steam locos including large passenger types at any one time which I find is enough for me to manage properly as I don't have a roundy-roundy track layout. In the unlikely event that I need more power, I can easily add a booster later. Hope that helps you.

[Phil S]

A universally useful, and economical tool, which can more than repay its own cost - even if a moderately priced model is bought - is a multimeter !

It can help you answer questions such as how much current my locos are taking, and how much power is needed, quite simply... to misquote H&M's original advertising at the time of Zero-1  ' just 2 wires' ... a red lead and a black lead ......   inserted in-line will measure current, and placed across will measure voltage.

When applied to a disconnected motor, it can tell you its resistance ... which can then tell you the maximum current it might take,  and therefore assist you in choosing whether a decoder is suitable.    

[For measuring dcc voltages or currents, directly, more expensive meters tend to have , more accurate processing - but a reasonable answer can easily be obtained from cheaper meters either via diodes/bridge rectifier, or measuring the current from the power supply to the controller]

 

Other factors affecting your answer will be : Gradients, if any, on your layout,  tightness of curves and complexity of junctions (increasing the drag of the train) and the length/weight and rolling resistance of your trains ... these factors will reveal themselves if you monitor your trains on your layout (I use RRampmeters)

Modern 00/H0 locos usually take 0-.25-0.5A each for their motors.  Lighting in locos and coaches/trains can add considerably - especially if they are still using bulbs and not LEDs !!  [ A 12V LED lightstrip probably uses 20mA per 50mm unless underrun ]  Whilst sound may 'claim' 1Watt output ... that is unlikely to be the average - but if it was... P=IV    1 = I x 15volts => 1/15 Amp  added per sound device.

 

[Crosland]

5 hours ago, woodyfox said:

I'm beginning to wonder if the amp rating at 2.5 will be enough to cope?

 

Easily, unless you are running old Hornby Dublo with worn out motors.

 

The physical size of the layout does not affect how much current you need. It does, as you seem to be aware, affect the wiring requirements.

[woodyfox]

Hi,

 

Thank you for all the replies. Very reassuring. The run will be continuous with gradients only present due to my poor carpentry. The smallest radius curve will be 900mm. Some trains may be heavy with a maximum length of around 2700mm. As Old-Dudders has appropriately said, I'll have to suck it and see.

 

Thanks

[rab]

8 hours ago, Crosland said:

 

Easily, unless you are running old Hornby Dublo with worn out motors.

 

The physical size of the layout does not affect how much current you need. It does, as you seem to be aware, affect the wiring requirements.

Sounds like youve got 'amp'le then!

[Ron Ron Ron]

You can never have too many amps.....

 

[mikeg]

I ran an O gauge layout with the same controller for several years and had no problems with power. The club I belong to also has a O gauge layout and that runs large locos also with plenty of power we have even had Heljan diesel locomotives running on both tracks pulling up to 12 coach trains no problems. So as others have said suck it and see.

 

regards mike