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DCC AC volts on EZ command

Started by db22, December 14, 2008, 03:42:51 PM

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db22

I know this must be in here somewhere but I have just done the prerequisite 1 hour of searching and have not found a definition of the AC volts from the EZ Command. I am reading 16.4v and sometimes as low as 14.X with 3 DCC trains on a total of 3 separate loops of 36 feet each. The reason for my check is that my 2-6-6-2 (with Tsunami) runs about half as fast as my other two locos. I have a few DCC turnouts but they should not draw current if they are not being actuated.
I have read that people are getting 19.1v. I also have read about using more than one source track for the power. Right now I only have one wire from EZ to the 3 circuits and they all connect to each other via the turnouts. I do not see a great deal of drop with everything running except when I switch a turnout. It seems to me that the voltage would start to sag if my total load was getting low enough to be sucking too hard on the EZ?

db22

Thanks for the response - I am using a Tektronix true RMS and I can also measure the frequency but, as you say, my results may be relative. I guess an easier guage would be other peoples experience with 3 locos on a total a total of 90 feet using EZ Command. I am asking before I invest in a booster or a different controller, I know Yampa Bob loves his EZ Command as do others but I might be on the cusp of capacity.

Rangerover

#2
Ok I'll take a shot..The EZ command stand alone is only 1 amp, if you read the directions that means you can run 2 dcc locos + 1 dc loco. so in order to operate the turnouts and 3 dcc locos you will need a booster. I bought the 5 amp booster from bachmann as an addition 3 years ago and I can run up to 9 dcc loco's, my switches and turnouts I still operate the old fashioned way, LOL I don't trust new technology until it's been used for a couple years such as the dcc turnouts. You need a booster in my opinion. I have 6 main lines and the longest 3 are over 60 feet each or a total of 180 feet just for those 3.  Hope I helped some! Jim

Jim Banner

The total number of feet of track has very little effect on track voltage as long as the track is properly wired to heavy enough bus wires or all the track joints are soldered.  Unsoldered joints with no bus wires will lead to voltage drops at the joints, sooner or later.  If corrosion of the joints makes these voltage drops dominant, then there may be no power left to run the trains.

Track voltage will also vary with power line voltage.  This averages around 120 volts but can vary considerably.  110 to 130 volts is common, 100 to 140 volts is possible.  Track voltage also varies with loading - the more current your trains (including lights in track powered cars) draw from your tracks, the lower the voltage goes.  A rating of 16 volts at 1 amp draw can easily rise to 19 volts at zero draw, even with a constant 120 volt line.  And it can drop below 16 volts if the current draw exceeds the 1 amp.  This drop in voltage with increase in load is of no great concern except perhaps in terms of brightness and longevity of incandescent lamps.  As far as speed is concerned, you, the operator, do just  what they do in the real world of trolley buses and street cars - to maintain speed, you adjust the throttle a little bit, just like you do on grades.  Only if the load exceeds the capacity of the command station, making it shut down to protect itself, do you have a major concern. 
Growing older is mandatory but growing up is optional.

Yampa Bob

#4
db22,

Yes, I do enjoy my EZ Command controller, but bear in mind I only have a single mainline of less than 20 feet, and seldom run more than one train at a time.

Personally, if I had 3 mains as you describe, and never planned to run more than 3 locomotives at one time, I wouldn't consider the purchase of a booster. If you can run the 3 locos at realistic speeds without the controller shutting down, you have nothing to worry about. 
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

mattallen37

Using the EZ-command, I can run more than 10 locos at once, but they go a lot slower, and even though it MUST be done right, I have used TWO bachmann transformers is parallel to get twice the amps, the result was SWEET (no booster necessary ;D) and trains do not bog down as much.
                                                 

                                                    Matt

Jim Banner

Connecting the outputs of two transformers together will give you a 50% chance of getting the two outputs in parallel.  Then your E-Z Command will have twice as much current available to it.  Hopefully the protective circuitry inside your E-Z Command can protect it from a current overload of this magnitude.

The other 50% chance is that you will get the two transformer outputs in series.  This will render one or both transformers inoperative in a very short time.

Growing older is mandatory but growing up is optional.

Yampa Bob

#7
Most modelers understand the mechanics of a locomotive, the motor shaft turns and the worm gear on the motor shaft turns the drive gears.

What happens inside the motor to make the shaft rotate might be a mystery to many. Here is one of many sites that explains the theory of DC Brushed (DCB) motors.

http://www.solarbotics.net/starting/200111_dcmotor/200111_dcmotor2.html

There are three principles that should be understood, the first is that the rotational speed of the motor is proportional to the voltage applied, the second is that the torgue is proportional to the current.

Since a standard DC power pack has low current output, the motors are designed for minimum current draw, at the expense of torque.

The third is that multiple motors are connected in parallel to the power source, if you have 10 motors hooked up in parallel to the source, the available current is divided among the 10 parallel paths.  If the power pack is rated at 1 amp output, then theoretically each motor will only receive .1 amp of current. (assuming similar motors)

http://www.facstaff.bucknell.edu/mastascu/elessonshtml/Basic/Basic4Ki.html
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

mattallen37

Quote from: Jim Banner on December 17, 2008, 07:04:16 PM
Connecting the outputs of two transformers together will give you a 50% chance of getting the two outputs in parallel.  Then your E-Z Command will have twice as much current available to it.  Hopefully the protective circuitry inside your E-Z Command can protect it from a current overload of this magnitude.

The other 50% chance is that you will get the two transformer outputs in series.  This will render one or both transformers inoperative in a very short time.


Yup, I know (that is why I said it MUST be done right). The E-Z Command did not even get warm.

Quote from: Yampa Bob on December 18, 2008, 01:21:39 AM
Most modelers understand the mechanics of a locomotive, the motor shaft turns and the worm gear on the motor shaft turns the drive gears.

What happens inside the motor to make the shaft rotate might be a mystery to many. Here is one of many sites that explains the theory of DC Brushed (DCB) motors.

http://www.solarbotics.net/starting/200111_dcmotor/200111_dcmotor2.html

There are three principles that should be understood, the first is that the rotational speed of the motor is proportional to the voltage applied, the second is that the torgue is proportional to the current.

Since a standard DC power pack has low current output, the motors are designed for minimum current draw, at the expense of torque.

The third is that multiple motors are connected in parallel to the power source, if you have 10 motors hooked up in parallel to the source, the available current is divided among the 10 parallel paths.  If the power pack is rated at 1 amp output, then theoretically each motor will only receive .1 amp of current. (assuming similar motors)

http://www.facstaff.bucknell.edu/mastascu/elessonshtml/Basic/Basic4Ki.html

Right, and with two transformers, they can each have 200 ma instead of 100 ma.

                                                 Matt

Yampa Bob

Matt,
I would be interested in hearing how many locomotives it takes to shut down the controller.  I have never pushed my controller to its limit as I'm not an advocate of destructive testing. Some have reported that it takes 1.5 amps of current draw before the overload protection shuts the controller down.  Due to my small single main layout, I have only tried 4 locomotives at the most.

In theory, the overload should protect the controller regardless of power input, but my concern would be in the case of a short that might pull a large current surge through the controller and cause damage, before the overload "breaker" activates.

The statement on page 4 of the EZ Command manual is perhaps misleading. The part that reads...... "May require additional power input", should probably read: ".......additional power input TO THE TRACK" , not to the controller. In other words, using a booster.

I won't commit to saying the way you operate is right or wrong, I can only say the manufacturer determined that a 1 amp power supply is appropriate for the EZ Command circuitry.  Other modelers should be aware there is an element of risk if the manufacturer's specs are exceeded.
I know what I wrote, I don't need a quote
Rule Number One: It's Our Railroad.  Rule Number Two: Refer to Rule Number One.

mattallen37

Quote from: Yampa Bob on December 18, 2008, 03:11:20 PM
Matt,
I would be interested in hearing how many locomotives it takes to shut down the controller.  I have never pushed my controller to its limit as I'm not an advocate of destructive testing. Some have reported that it takes 1.5 amps of current draw before the overload protection shuts the controller down.  Due to my small single main layout, I have only tried 4 locomotives at the most.

In theory, the overload should protect the controller regardless of power input, but my concern would be in the case of a short that might pull a large current surge through the controller and cause damage, before the overload "breaker" activates.

The statement on page 4 of the EZ Command manual is perhaps misleading. The part that reads...... "May require additional power input", should probably read: ".......additional power input TO THE TRACK" , not to the controller. In other words, using a booster.

I won't commit to saying the way you operate is right or wrong, I can only say the manufacturer determined that a 1 amp power supply is appropriate for the EZ Command circuitry.  Other modelers should be aware there is an element of risk if the manufacturer's specs are exceeded.

I have a small layout right now, so I can only run 10 locos, but it did not shut the system down (with only one transformer), they just ran at less than half normal speed. I actually do not even remember reading "may require additional power input."

                                                   Matt

Hunt

Assume and speculate ...  the two headed menace that waste time.
;D

Hunt

QuoteThe E-Z Command Control System is rated at 1.5 amps. You should use the transformer supplied with the unit.  If you need additional power then you should connect your E-Z Command to a more powerful DCC booster for more power.
To date this is Bachmann's written position on the subject of more power for their E-Z Command Control Center, Item No. 44902

Notice the 1.5 amps is more than the 1.0 amp output printed in the E-Z Command Setup and Programming Instructions.

grumpy

I have been running my EZ Command with a 5 amp power supply which allows me to run additional trains than that suggested by Bachman. I have had no problems . All seems to run well.
Don

Hunt

Quote from: grumpy on December 19, 2008, 12:52:28 AM
I have been running my EZ Command with a 5 amp power supply which allows me to run additional trains than that suggested by Bachman. I have had no problems . All seems to run well.
Don
Don,
Please!  Following your information is going to cause someone to possibly ruin their unit or worse.

Jim Banner and I have covered with you the potential hazard of using of a 5 amp transformer.  If the overload shutdown is still working in your unit, I know you are NOT drawing anything close to 5 amps through the E-Z command unit.