I'm attempting to adjust the decelation on an MTH GG-1 so that it stops in a shorter distance. The manual page indicates that engine has MTH PS3.0 electronics. Changing the value in CV4 from the default value of 0 (zero) seems to have no effect. I noticed that CV54 is identified as MTH Deceleration Rate with a default value (decimal) of 64. The deceleration formula is given as 1/8*sMPH/s. I increased the value stored in CV54 and got the locomotive to stop in a somewhat shorter distance. Is there anything else I can do?
0 in CV4 means no momentum. So, that's as low as it can go. If MTH uses CV54, then adjust that. Higher number should increase the deceleration rate. They don;t say what the maximum value is, try 255, which would be the normal maximum for a CV. That should make it slow down at a rate of 32 smph per second.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Hi Old.Professor,
Protosound 3 decoders by default use a different calculation for acceleration and deceleration rates. CV 3 and 4 don't do anything unless you turn on "PWM mode" using CV52. As you surmised, to get a shorter stoping distnace in the default SMPH mode, you enter a higher value into CV 54 (MTH deceleration rate). The default value is 64, which equates to 8 smph/second of deceleration. As Randy suggested, the max value is 255, which will give you a deceleration rate of 32 smpgh/second.