Digitrax DCC power issues

[RobBrooks1]

Another quick question!!00 

I have a  11x8 foot  00 gauge DCC layout powered by a Digitrax DS51 controller and 402 wireless throttle. I have about 20 sound locomotives on the layout mostly in the fiddle yard and sidings.

The DS51 provides 3amps DCC power with voltage at 11v. Am wondering if this is a bit low.

Locos have seemed to slow down  a bit but could this be to power draw from the locos? Point motors are 25 Cobalt IPs which don't draw much current. 

My question is whether power supply would improve by adding a Digitrax 5/ 8amp booster  ( as in Empire Chief) to the layout or do I need to create power districts? The booster could be connected by loco net and the DS51 plugged in to use as a throttle. 

All suggestions gratefully received.

[Ron Ron Ron]

First of all, the track voltage at 11v which does seems rather low.

I thought the Zephyr track output was supposed to be something like 13v ?

The NMRA nominal value for N is 12v and for 00/H0 15v although decoders should be able to work down to an absolute minimum of 7v (minimum track output allowed is 8.5v).

Sorting that out might improve the slowing down, however there may be other factors at play, such as the layout wiring being sufficiently up to scratch, or an electrical problem with the wiring.

Has the Zephyr been tripping out?

 

As for adding more power, or rather a better and more reliable track power supply, installing an additional booster is your choice.

If you do go for the extra booster, 5 amps should be more than sufficient to supply the whole layout on its own, but as to how you arrange the track supply may depend on several factors (e.g. track geography, ratio of active locos stationary or idling in the fiddle yard to those running out on the track etc,).

 

Just one suggestion.

Are the point motors fed from a separate accessory bus?

If so, an accessory bus could be powered directly from the Zephyrs' track output, with the 5 amp booster supplying the track bus and running the trains.

The 5 amps would be plenty to run a single power district, which could be divided into a number of sub-districts, each protected by circuit breakers.

 

.

 

 

Edited July 9, 2020 by Ron Ron Ron

[norman]

Hi Rob

I'm wondering how are you measuring the 11 volts?  and hope not with a simple multi meter because the value will be incorrect.

 

[RobBrooks1]

Hi Guys,

It has been some time since I logged onto the site and I saw your replies.

Firstly in later summer I installed a DCC concepts Alpha power meter which gave a fixed reading of 12.74 volts. Most of my locos were OK with this but I still had issues with running with a couple of locos possibly due to the number of idle locos on the layout.

Next I purchased a DCC concepts Alpa power box on the layout and wired the Zephyr into this. The resulting power was much better on the meter 17v + on the meter and the locos ran well especially  my sound Blue Pullman which had an extra turn of speed.

An interesting issue then occured. I have a Digitrax DS64 which is wired in to digitise 3 DCC concepts analogue point motors. Suddenly this would default to a solenoid point motor setting and needed to be reset halfway through the operating session.

All my other IP point motors which get power from the track bus remain unaffected. I have some spare Ip's which I hadn't  installed so will disconnect the DS64 and connect in the 3 IP motors.

I am wondering if any one else has had this issue? It is annoying having to reset the DS64 and sometimes it takes several attempts under the boards to reset it which can be frustrating. It has worked ok for the last 6 years and suddenly due to the increase in power from 3 to 5amps, suddenly started to play up

 

 

 

[Crosland]

The higher track voltage will also make any peaks due to noise higher. I would try fitting a simple filter to the track bus. DCC concepts will sell you one https://www.dccconcepts.com/product/new-bus-suppressors-terminators-2-pack/ but the Resistor and capacitor would cost you pennies if you bought them yourself. 

[Nigelcliffe]

I suspect your issue with the DS64 may be down to DCC wave-forms, rather than voltages.   Something about the output of the Alpha box and the DS64 don't agree and cause a reset.    You could try fitting "snubbers" (couple of cheap components) to the DCC bus to see if that fixes things.   ( I see Andrew got there while I was typing). 

 

Another option is to split your DCC bus - take the output of the Zephyr, and send that direct to the DS64, and at the same time, the Zephyr goes into the Alpha which feeds the track.    So, your DS64 stays outside of the track supply.  

 

The Zephyr models I'm used to can take quite a wide range of input voltages.  The track output voltage is a bit lower than the (DC) supply input.  So, a different PSU will change the track output voltage.   The DCS51 manual says it can take up to 16.5v DC.  ( There are a number of different Zephyr models over the years, so anyone else reading, check the power supply details in the manual for your version of the Zephyr).