full load amps for 2-8-0 consolidation

[CanWest]

Hello,
Could you tell me what the full load (just before wheel slip) current draw is for the 2-8-0 Consolidation. I am trying to size an analog throttle correctly.
Thanks for your help.
Hal

[erider2002]

Hal,
I am running mine in DCC mode and using a Tsnuami decoder. Just before wheel spin the 2-8-0 is drawing @ 20mA DC, at running speeds it is drawing @15mA DC. At standstill it is drawing @ 30mA DC. I used a Fluke 87 for these measurements.

Paul

[NarrowMinded]

I know nothing about dcc but why does your loco draw more mA while standing still?

[CanWest]

Hi all,
I forgot to mention that I will be running this loco analog. Sorry about that oversight.
Hal

[CanWest]

For anyone who might be interested:
I put together a little test set up and found the following:

At 12V dc (Half wave) the loco draws 0.45 amps just before wheel spin and 0.6 amps in a locked rotor (motor stalled) condition.

Hal

[Jim Banner]

Paul,
I am wondering why your Fluke 87 produced such low readings.  This is a good meter, true RMS and all.  Did you have the meter in series with one of the track feeds?  Did you have it on an ac current scale or a dc current scale?  If a dc current scale, then I suspect you might have been running an analogue locomotive and left the speed turned up a bit.  Otherwise, the meter should have read zero.  If you were using an ac current scale, the meter would have been affected by the waveform having some of its energy above the 2 kHz cut off frequency of the 87, but I would be surprised if that caused such a large error.

On 12 volts straight dc or full wave rectified ac I would have expected about 1 amp locked rotor.  And about half that just before wheel slip.  Measuring the ac current from a DCC command station should have been about the same unless you had Vmax turned down inside the decoder or the throttle at less than full speed during the stall current test.  I am mystified.

Jim

[erider2002]

Jim,

I re-checked my DC values and they appear correct, what I didn't do was to check the AC values. The AC values are: @40 mA AC at idle, @150 mA AC at slow speed and @320 mA AC at wheel slip ( I didn't check locked rotor). I am running an un-modified from stock Tsunami sound decoder. The meter was connected in series with the loco.

I'm still getting used to this DCC world, but I'm guessing that the odd DC values are attributed to the digital control. At the moment I am using a low end Bachmann controller, I need to get a better one so I can start playing with the CV's.

Paul