QSI Sound System

[rockislandnut]

QUOTE: Originally posted by cacole

DCC systems do not put anywhere near 18 Volts on the track -- most put 14 Volts. 18 Volts would burn out every lightbulb in a passenger car. DC power packs put out up to 16 Volts DC with no load, but the voltage output drops as the load increases, so they are rated at a nominal 12 Volts. In order to measure the output voltage of a DCC system, you must have your meter set on AC Voltage, because the DCC command signal is a square wave, high frequency AC comonent superimposed over the normal 12 Volts DC track voltage, thus raising the measured voltage to 14 Volts.

Sorry but yes some DCC systems do put more than 18 volts on the track all the time and some DCC systems are regulated like my "Digitrax Zephyr", it produces a steady 13.7 volts DCC measured by "Tony's Train Xchange" RRampmeter. Do not use a VOM to measure DCC track volts for you will come out with the wrong voltage everytime. "Digitrax,NCE,Lenz and others of different models will produce up to 22 volts DCC and this is adjusted manually to your likeings allthough 22 volts DCC is probably way too high and a QSI decoder will shutdown after 21.5 DCC volts ( Not 21.5 volts AC ) . Anyone who runs lights in their passenger cars useing DCC should install the correct resistors/varible resistors and you won't have the problem of your pass. car lights burning out. Bast way to go on lights is with LED's with the proper resistor.

[Anonymous]

Man, you guys are great. I found everything I wanted to know and then some. I think it probably would be wise to go ahead and make the jump to DCC. I'm looking real hard at the MRC Prodigy Advanced system. If you guys have any input on that I would appreciate it.

[rrinker]

Overheating of DC motor on DCC has little to do with the fact that the voltage is always at maximum, and a lot more to do with the fact that the DCC signal is square wav AC. Standing still, the motor is goign from full forward to fill reverse hundreds of times a second, without EVER turning, so yes, it will heat up. But for those DCC system that allow control of an analog DC locomotive, as long as you keep it moving and don;t leave it stand in one spot, there generally will not be a problem. This applies to such motors at blue box Athearn 'tan can' motors and other large motors like that. Coreless high-performance motors WILL burn up fairly quickly on the DCC signal, simply because they do not have a solid iron armature core to help dissipate any heat build up.
Now, being able to stand the buzz is a different story, although the buzz is usually cause by motors that do not have the magnets firmly glued in (ie, Athearn), so they vibrate against the motor case. But with quality decoders being available for around $14 now (TCS T1, 'street price'), it's a lot easier t just install a decoder. Sure better than a few years ago, when a 'economy' decoder was one that sold for $30.

--Randy

[cacole]

DCC systems do not put anywhere near 18 Volts on the track -- most put 14 Volts. 18 Volts would burn out every lightbulb in a passenger car. DC power packs put out up to 16 Volts DC with no load, but the voltage output drops as the load increases, so they are rated at a nominal 12 Volts. In order to measure the output voltage of a DCC system, you must have your meter set on AC Voltage, because the DCC command signal is a square wave, high frequency AC comonent superimposed over the normal 12 Volts DC track voltage, thus raising the measured voltage to 14 Volts.

[Modeloldtimer]

DC Track system voltage is 0 to 12Vdc. Lomotives with Dcc decoders run on track
Voltages of 12V and up to 14v. DCC track voltage is continuosly on at the 14 Volts.
When runing engines without decoders on Dcc rails the engine motors can over heat after a short time due to the higher track voltage staying on. Notice when runing non-dcc engines on DCC, the motors Buzz, makes noises and heats up from the excessive voltages. MU engines with DCC decoders and run the non decoder engines on rail sections wired for DC voltage control. Short runs of non-dcc engines on Dcc rails is ok.
( Corrected err in the way I had voltages listed I used uper voltage limit of 18v. which would be ok for a larger scale than HO )

[Anonymous]

I have sucessfully MU'ed the BLI Heavy Mike and the M1a using DCC Consist. I have a several engines that dont use DCC and are built in MU with all units powered. One of the things they need to be able to do is get along and "share-alike" and not fight each other at low speed.

I am not going to attempt to MU a BLI engine with a non QSI (Or non BLI) engines anyway.

If you find you need a helper on that heavy train, you can use the old prototype tricks such as doubling the hill.

[Anonymous]

QUOTE: Originally posted by cacole

I think what they mean is that because the QSI equipped locomotives require a higher than normal throttle setting before the motor starts to turn over, you cannot MU the Broadway Limited with non-QSI equipped locomotives. As long as you are running MUs of Broadway Limited there should be no problem, but I wouldn't try to MU a Broadway Limited with an Athearn Challenger, even though both have sound, because Athearn doesn't use the QSI sound system and it probably has a different start voltage.

The new BLI PRR K 4 will not MU on DC with other BLI engines because of the engine inertia option. It automatically starts slow even with the DC on full and can be controlled to some degree, but it will not MU with anything on the planet except maybe another BLI K4. It is sort of like the DC momemtum that some Power packs use.

[Anonymous]

I think you're right, as cacole says, it takes more voltage to run these locos, so one with and one without can't be MU'd, but if both draw the same it should work fine.

[Anonymous]

AntonioFP45 is right on the money/ In dc your are not m.u. ing anything just several engines all fighting for there share of the track power.With dcc and the ability to program each indivual loco to match the Main unit you can run several different loco's without heating up a motor because of the tug of war between different engines and their respective performance.I run a BLI Mike with a Older Rivarossi digatrax equipped Hudson and they operate fine.You might want to consider a good Dcc system before dropping a load on several qsi equipped loco's so you can enjoy all of the benifits of decoder equipped loco's.

[AntonioFP45]

One of the advantages of DCC is that this wouldn't be a big problem. With patience a modeler can set up Individual decoder equipped locomotives with various starting voltagescan be adjusted using CV's on the DCC controller. So basically a BLI, an Atlas, and a P2K can be adjusted so that they can run together in MU.

This is one of the features that I like about DCC so much since I'm going to have a batch of locomotives in the SCL paint scheme that need to be able to MU together without "fighting". P2k, Atlas, and Mashima equipped Athearns can play tug-o-war with each other at low speed in an MU lashup.

I'm definetly thinking about a BLI F7 (if the horn is a honker) and a BLI SD40-2.

[PennsyHoosier]

I agree with cacole here. I'm quite confident that what that means.

[cacole]

I think what they mean is that because the QSI equipped locomotives require a higher than normal throttle setting before the motor starts to turn over, you cannot MU the Broadway Limited with non-QSI equipped locomotives. As long as you are running MUs of Broadway Limited there should be no problem, but I wouldn't try to MU a Broadway Limited with an Athearn Challenger, even though both have sound, because Athearn doesn't use the QSI sound system and it probably has a different start voltage.

[Anonymous]

I'm contemplating purchasing several locos featuring the QSI Sound System. My question regards the comment at the end of the description. It states that due to the higher voltage required, non-sound equipped locos cannot be m.u.'ed in dc. To me this implies that locos equipped WITH sound CAN be m.u.'ed in dc. I haven't converted my layout to dcc yet and was just wondering if I can run multiple lash-ups as long as all of the units are sound equipped.