MUing For Dummies.

Should turning BEMF off cause
a huge speed reduction?

Above posts are all BEMF on.

Thanks,
Loco1999

 

Loco1999:

6 is 35
7 is 37
8 is 39
9 is 41
10 is 45
11 is 49 or 50
12 is 55
13 is 59
14 is 64

Try those values with the BEMF turned off and then turn it on when the values are set to see what happens.

Stay cool and run steam....

 

"Ok on a newer slow speed engine
are increments of 4 to much?
(This is a too slow running tunnel motor.)"

Loco1999:

On a slow speed motor, the increments of 4 aren't too much. You have to test the values to see if they meet your requirements. You can always decrease or increase the values to meet the needs of the loco.

BTW; I'm glad the kapton tape worked. I still have a few tricks left in the bag.


Stay cool and run steam......

 

Thanks for the info and ideas.

I started over again.

I finally got them matched.

The MU runs good now.

Thanks,
Loco1999

 

Loco1999:

How close were the values between Speedstep 6 and 10?


Stay cool and run steam......

 

I know it's different numbers this time...
I changed the tunnel motor numbers also.


Step TM SD50
1 60 44
2 64 46
3 68 47
4 72 48
5 76 50
6 80 53
7 84 56
8 88 59
9 92 62
10 96 65
11 100 68
12 104 71
13 108 74
14 112 77
15 116 80
16 120 84
17 124 87
18 128 90
19 132 92
20 136 94
21 140 96
22 144 98
23 148 100
24 152 102
25 156 104
26 160 106
27 164 108
28 168 110


Loco1999

[ March 19, 2005, 06:54 PM: Message edited by: loco1999 ]

 

Loco1999:

It's interesting how those to loco's match up speed curve wise.

The SD-50 with the old fast motor and the slow speed IM TM.

Thanks for posting the results. I was curious how they matched up.

In my posts above I just gave you "for instance values".

Stay cool and run steam.....

 

Thanks for the info.

It's very difficult the first time.
The fast motor didn't help either.

I cleaned the track and started over.
I set 55,56,57 to defaults 128,48,6.
I set 3 and 4 to 0 and 65 to 0,
also 66 and 95 to 128.

The slow speeds are pretty tough,
It gets easier as the speed increases.

The match will never be perfect,
do they run better at x, x-1, or x+1.

The MU doesn't move until step 4
if they are pulling a bunch of cars.

Loco1999

 

Loco1999 stated "The MU doesn't move until step 4
if they are pulling a bunch of cars"


Loco1999:

Try turning off the BEMF and see if the loco's start up immediately.

You should set values for CV 66 which will give your loco's a jump start. Set CV 66 (trim) to a value higher than CV 67 for both loco's by +30 to +40.


Stay cool and run steam......

 

Do you mean 65 KickStart > 67 Step1 ?
( or 66 ForwardTrim > 67 Step1 )

BEMF is on, BEMF off makes
the engines even slower.

Thanks,
Loco1999

 

Loco1999:

Try kick start for the loco's.

Stay cool and run steam.....

 

Thanks for the info.

Not much difference with the kick start.

I was using DH mode to speed match.

Should I be using MU instead?

Thanks again,
Loco1999

 

Loco1999:

I only use MU mode to speed match.

I never liked DH mode.


Stay cool and run steam......

 

Thanks.

I will start over again with MU.

I think it will be easier now,
after all the practice.

Loco1999

 

I didn't change anything yet.

I just changed cv57 in both
locos from 6 to 66.

It runs really good in a MU now.

Can anyone explain what is going on?

Thanks,
Loco1999

 

I found it,

To get 6 for cv57 in normal or MU,
you need hex '66' so decimal 102.

Loco1999

 

Loco1999:

Doesn't CV 57 have a range of 0-15?


Stay cool and run steam.....

 

It holds two hex digits 0-F ( 0-15 decimal ).

Read this.......

"The first hex digit controls the amount of droop in effect when speed is controlled using the standard decoder 2 or 4 digit address. The second hex digit of the CV value controls the droop in effect when the decoder is part of an advanced consist for speed and direction control. Values for each digit can range from 000 to 015 decimal or x00-x0F hex."

info quoted from...

http://www.digitrax.com/v1/speed%20stab.htm

I was running all MU's with BEMF off.

What a difference.

Loco1999

 

Loco1999:

I use these CV to adjust the BEMF in all consists that use the Digitrax decoders.


Stay cool and run steam.....

 

Thanks for the help.

I just didn't get that part of it.

Now it's really cool.

Loco1999