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Pat and I are here to give you all the help and advice you may need. Whether you want to go DCC or if you have a problem with your ZTC equipment the phone is the way we can give you our best and fastest attention. So call us on 01823 327155 between 9am and 9pm 6 days a week. Mondays we are closed (we are playing with our layout at the club).

Imagine a simple oval of track work and a passing loop. The track work has no isolated joints or isolation switches and is connected to the main controller by only two wires.

Now lets put all of our locomotives (and it could be up to 9,999) on the main track and provide a controller to each engine driver, which could be up to a maximum of 16. Each Driver can now control his own locomotive with complete and total freedom and in isolation from any other driver, just as if they were in the cab. This of course means that drivers must read the track and obey the signals, or accidents will happen just like on the real thing.

It will not be very long before two locomotives are running in opposite directions and the usual result would be a collision. However if one of the locomotives, under full control is run into the passing loop and slows down to a crawl then the other locomotive can safely pass and all will be well. When the line is free the points can be re-set, the signals set to on and the driver can pull locomotive and its train of coaches or wagons away to resume it journey.

The first response is usually, “So DCC is only suitable for large layouts” which is certainly not true. The small layout can often derive more benefit from DCC control. Many British layouts only cover a few square feet in size, but the operator still requires to control more than one loco on the same restricted length of track. To achieve this numerous isolation blocks are normally required. This makes prototypical operation around a Loco Depot, Goods Yard or even on a branch line for example very difficult. The more locos you have the greater the number of isolated sections required just to enable the locos to remain stationary whilst only one other loco is moved.

DCC dispenses with this serious limitation and permits any loco on the track to remain stationary or move independently. Sometimes more than one at a time will need to be moved such as when double heading or running a banker. In addition with the use of Accessory Decoders all of the point operation, track work routing and signalling can be accomplished via the same two feed wires.

This then is the full wonder of DCC control; multiple locomotives all under independent control and all on the same track, which in turn is connected to one or more controllers but only by two feed wires.

Unlike earlier digital systems the strength of DCC is that an international body called the NMRA controls the locomotive to track work interface. This ensures that the thirty or more world wide manufactures products, are all interchangeable at the track interface. 

DCC Systems supply AC voltage to the track, unlike conventional control systems. The frequency of the AC signal varies and this variation contains th digital information which is used by the decoder in a locomotive to generate a DC control voltage. This is applied to the DC motor which powers the locomotive.

Because the supply voltage is AC, there is no bias to one direction or the other. The DCC signal sent to the decoder determines the direction of travel, which for convenience is labelled ‘forward’ and ‘reverse’.

Transposing the red and black wires (DCC supply) will not alter the loco’s direction of movement, but transposing the orange and grey wires (DC) will do so. 

Yes without any problem but you will need a ZTC 310 when driving Tortoise, Fulgarex, Lemaco, LGB or Kato Point motors all of which come into this category. 

We strongly recommend the use of a Capacitor Discharge Unit (ZTC 360) to provide the high pulse currents when solenoid point motors are used. This will improve their operational reliability without starving the track or locomotives of their running power.

Solonoid point motors by their nature are very variable in operation. Friction in the point mechanism and between the point base and layout base board also contribute to the overall stiffness in a point which has to overcome by a finite amount of energy available from the point motor.

The energy required for the point motor is dependant on A) The voltage applied to the terminals of the point motor and B) The current available from the supply. The ZTC 360 provides almost unlimited current for a short time thus enabling the point motor to operate.

It should be noted that Solenoid Point motors such as PECO and Hornby are designed to operate from a 16 AC supply. Normally an AC supply is a sine wave, which means that the peak voltage across the point motor coils is 22 Volts, plenty to provide a good level of operation.

DCC on the other hand for 00 gauge generates a 14Volt square wave signal, which is insufficient to operate most point motors. It is possible to increase the output voltage from your 511 or 505 to a about 17 volts to improve the point motor performance – see section 4.1 of the manual. Do not exceed this value as some locomotive decoders maybe affected adversely and it is also not advisable for N gauge layouts. A superior solution is to power your solonoid point motors via a separate bus powered by a booster and 560 transformer.

Our new 302 combined point motor and decoder overcomes all these difficulties and will happily operate on 14 volts. 

Yes, except when using the old H&M Point Motors. These H&M Point Motors draw too much current to be doubled up per channel. 

The UN-powered storage life of the CV values is defined by the Microprocessors used within the Decoders. The microprocessor life is quoted by the manufactures as greater than ten years. It is possible however that under extreme environmental conditions that the CV values may be lost. For this reason it is always worth keeping a hard copy or backup of the various CV values stored in a particular Locomotive. They are also useful to return to if you purchase a similar locomotive at a later date. 

Any kind of DC motor can be operated with a suitable DCC decoder. ZTC decoders have been designed to take the need of our customers into account at all levels and our decoders will drive the smallest coreless motor drawing less than 50 mA up to large moving iron motors which draw 2 Amps. 

The current software version for the ZTC 511 Master Controller is V4.01 The current software version for the ZTC 521 Slave/Master Controller is V4.02 The current software version for the ZTC 620/622 Slave Controllers is V4.01 

You can use either type of point work but we only recommend the use of electrofrog as these will give superior running if wired correctly to the manufacturers instructions with the addition of polarity switching for the frog. Insulfrog points can be modified to improve the running performance and details of this modification will be published on the ttmrc website ( This will include step by step photographic instructions for the conversion. More information (on most manufactures of track point-work) can be found on this subject by referring to the website

All ZTC products are supplied with a full set of Connectors. In addition a complete set of operation and installation Manuals are supplied with your first purchase of each product. Additional manuals and any updates are available free of charge from our web site at Additional copies can also be supplied by calling our sales office on 01823 327155 

This is not a mandatory requirement but the Track Power Indicator Lamp provides a simple, clear and positive indication of the track status, that can be seen at a glance from all parts of the railway room and is a nice feature to have. No Track Power Indicator Lamp should be fitted to the programming track output as the additional load could cause programming problems. 

There are two reasons for providing Track Isolation Switches between your track work and the controller. Neither is mandatory. Both reasons are based on good practice and discipline and are proposed to avoid locomotive operational difficulties. No Damage will result if the rule is disregarded.

First, you should understand that the Main Controller is a computer-based product that talks to another computer- based product, the Locomotive Decoder. In this case the communication with the second computer is via the dedicated AC track power supply. Like other computing devices, poor quality power supplies or power interruptions (which are normally referred to as “Brown-outs”) can and do adversely affect the performance of the equipment. This is true of most computer-based devices.

Secondly, Most “Track Shorts” occur when locomotives or rolling stock, are being put on to the track. This is due to the bogies etc. moving about with a will of their own. Switching off the track power eliminates the resulting problems of electrical sparks, which can not only damage the delicate flanges of the wheels on modern locomotives but also corrupt the CV values programmed in the decoder. It is almost impossible to remove or replace a locomotive on to the track cleanly. This is due to the many dangling or sprung wheels fitted on locomotives. We therefore always recommend that it is a “good practice” to turn the power off for the short time that it takes to accomplish this regular act.

As locomotives are often programmed on a separate length of track it seems logical that we should also recommend that an isolation switch should also be fitted in the lead to the programming track. We stress that the fitting of such switches is not mandatory, just very good practice. 

Yes. Just put the locomotive on the track and select Loco 0 from the Control panel. One of the clever features of DCC is that it will now control this single locomotive as if it has a decoder installed inside. This is fine for all electric motors fitted in ready to run locomotives such as Hornby or Bachmann. However care should be taken with kit-built locomotives. Most are fitted with standard 3 or 5 pole motors and are fine, but a few may be fitted with coreless motors (such as the RG4 and RG7) and should not be run as Loco 0, otherwise damage to the motor will result. 

Yes. Providing it has a pure DC controller, not one with Feedback features. When the controller is first turned on nothing will happen. Then when 5-6 volts are sent to the track the decoder will wake up and then the decoder will apply a variable voltage between 0 and 12 volts to the motor. Depending on how far the controller is turned up above the 5 or 6 volt starting point will depend on how fast the locomotive runs. The locomotive will stop when the voltage is reduced to the 5-6 volt starting threshold. 

The Answer is Yes.

ZTC Controls Ltd has specifically designed all their products to be compatible from Z through to Gauge 1 and Larger. 

The main feature of a Feedback Decoder is to maintain a constant locomotive speed as defined by the regulator setting on the controller, regardless of whether the locomotive is travelling up or down hill or along the level track.

A secondary and beneficial effect is that they promote smoother and more reliable slow running of a locomotive. This is due to the circuitry and software within the decoder which has been designed to overcome stiff or tight spots within the locomotive mechanism by momentarily turning up the power to the motor, when it encounters a tight spot. 

At this present time ZTC Controls Ltd do not have a Radio Controlled Hand Controller in their range. This is due to the very low demand at this time for this style of product. However we are constantly reviewing our customers needs and as demand appears to be increasing for this style of product, then we will be adding it to our product range in the near future. 

All DC driven locomotives will work with ZTC Controls Ltd system. These days some are classed as DCC ready and require a decoder from our ZTC 4000 range. These decoders can be just plugged into the locomotive. This requires no electronic skills whatsoever.

All other locomotives, which are not classed as DCC ready, can be fitted with one of our standard range decoders. This requires that the wires from the motor are removed and then soldering the four decoder wires to the motor and pickups.

In some rare cases minor modification to the locomotive maybe required for allow the decoder to be physically located in the locomotive. To assist with some of these more difficult locomotives we offer a decoder fitting service. The cost for this service for 00 locomotives starts at £15 and never exceeds £35. As a matter of interest we have yet to find any locomotive regardless of age or size in which we have been unable to fit one of our decoders. 

At Taunton Controls we are very aware that DCC is both new and technical. It is not difficult however just different. Providing help to users of DCC is one of the cornerstones of our business. We pride ourselves in providing a high level of technical assistance both before you purchase and afterwards. Our Help line 01823 327155 from 9am to 9pm 6 days a week and if you are considering changing to DCC please contact. In addition we will be holding regularly DCC Training Workshops, at showroom in Somerset Our help desk can provide up to date information on these events so please call.

Best of all why not come and meet the Taunton Controls Ltd team at one of the many exhibitions that we attend. There you can discuss your technical questions, handle the products and even purchase goods. We look forward to meeting and talking with you and demonstrating our products. 

Any type of point motor can be used for DCC and they can all be driven from the ZTC 304 Accessory Decoder, but some require adapters to convert the output.

We do however recommend that it is best to use our 302 combined point motor and decoder. This unit is easy to use and designed to fit Peco and Hornby points directly or maybe mounted remotely using the Peco adaptor base. It takes approximately 20 Minutes to fit and wire and you have a full working DCC point control. 

From time to time the ZTC 505, ZTC 511 software is updated to incorporate new ZTC Controls Ltd. features or other software enhancements, or to incorporate changes brought about by improvements or alterations in the NMRA specifications. All new products are always supplied with the latest software release, but the facilities exist within the products to enable any vintage to be updated to the latest software standard by purchasing a software upgrade.

It is not mandatory that software upgrades are incorporated in your controller but it is advisable. This will enable the full operational facilities of your equipment to be utilised. In most instances the owner plugging in a replacement software module to the ZTC products achieves this. Alternatively the product can be sent to our service department where the work can be quickly undertaken. 

Assuming you are operating OO gauge then you will need to fit a power booster, when your track gets to approximately 500 to 750 feet in total length, to avoid data corruption due to the loading of the track work. This figure includes all sidings and run around loops etc.

Data corruption usually manifest itself in a Varity of ways all related to erratic running. Locomotives are also slow to respond to commands sent to them and in severe cases can even run away for no apparent reason.

Alternatively if you are actually running about 6 or more locomotives at the same time you will be drawing approximately 0.8 Amps per locomotive. But this is a variable and can range from 300 mA to 1.5 Amps depending on the age and manufacture of your locomotives. The output current of the ZTC 511 master controller is 5 Amps, so if you exceed this output figure you will also need a power booster.

You must remember that a Locomotives just standing on the track draws about 25 mA to keep the decoder alive. Therefore a hundred locomotives will draw about 2.5 Amps standing still (not running or pulling a train). This leaves about 2.5 Amps to run trains, which using our typical figure above will now be a maximum of three.

Finally the ZTC 550 is also an Intelligent Booster and can be used to automatically set the polarity for track networks such as turn round loops, Y-junctions and turntables. In the case of turntables we do make a specific product for Fleischmann turntables, which provides both the polarity switching and power for the control electronics. This is the ZTC 555 Intelligent Turntable Booster. 

We NEVER recommend the removal of the suppression circuitry. 

First, it is illegal for us, or for that matter any other manufacturer to recommend the removal of a third parties EMS suppression devices. These components are fitted to ensure that the products do not interfere with TV`s and the like, which causes a nuisance and inconvenience. However this also includes some much more important items such as Pace Makers which are life critical.

Secondly, all of ZTC`s Decoders are designed to work with these components installed, as we believe are those produced by other manufactures, but only they can confirm this.

Thirdly, These components are also a necessary requirement to enable the various locomotive manufactures to obtain the obligatory EMC approvals. This testing permits them to print a CE mark on their products, which is also a legal requirement for all electrical equipment sold throughout the European Community.

In an effort to try and clarify this recurring confusion, ZTC Controls Ltd. formally tabled the question at the NMRA DCC working Group (of which other DCC manufactures and we are members) in September 2004 in Salzburg.

The question was “Does any manufacturer of DCC decoders recommend the removal of the locomotive suppression components when fitting a decoder in to a locomotive”. There were 30+ members present and not one said that they would, or do recommended their removal. The working group then minuted this fact.

This information was picked up, and later published on the Yahoo DCC web site by a qualified EMC Engineer, but the myth still seams to prevail that they should be removed.

Incidentally tests conducted by ZTC engineers indicate that many decoders properly installed, from a variety of manufactures including ourselves often do not work as well with these components removed.

In addition to the obvious ones raised above, why not consider incorporating a locomotive yard or wagon shunting yard. Small movements of locomotives, going on while the main layout is running are something for a second operator using a slave controller (ZTC 622). 

In addition consider incorporating a fully automatic hidden turn round loop driven from an intelligent Booster (ZTC 550). This feature will permit a locomotive and train to leave a station in one direction and return in the opposite direction without stopping.

Another possibility is to consider running trains with lighting in the carriages this can either be on all the time or use a ZTC 255 decoder to switch off compartments at will or even whole coaches at a time. Some modellers have fitted locomotive smoke units, door lights on modern rolling stock, working pantographs and even opening sliding doors using memory wire. We have on our demonstration stand a mechanism, which operates both wagon and locomotive coupling/uncoupling hooks with an onboard actuator. This enables locomotives or wagons to be uncoupled at any point on the layout without the use of under base board magnets or ramps between the rails. We have even fitted this uncoupling mechanism in to a 00 gauge empty Bachmann wagon.

Finally it is possible with newer decoders and track accessories such as the ZTC 335 to incorporate locomotive detection, automatic slowing, automatic stopping in front of lights. Locomotive can even shuttle between two points with intermediate stopping at any number of locations such as stations.

A: The Layout Power Bus is nothing more than two wires which are installed around the whole length of your layout. The wire should be of sufficient size to accommodate the highest current likely to be demanded from the controller by a load. In practice this is typically 5 Amps. 

High currents usually only occur under fault conditions, for example when a short-circuit is generated by a simple derailment of locomotives (or some other rolling stock fitted with metal wheels) at the V of a point, or the locomotive drives over a point set incorrectly. It’s also possible for short circuits to occur during the wiring phase of the layout or if a fault develops during the operating life of the layout.

The size of the wire is therefore important and depends on three factors a) The maximum current output of the power station/controller, b) The overall track length of the layout and c) How many locomotives you intend to have either running or standing stationary on your layout.

Recommendations do also vary on whom you speak with, and generalities are often misleading as they can only take into account a set of specified conditions. In practice we at ZTC Controls Ltd. strongly recommend the use of our ZTC 320 Self Adhesive Copper Tape for the DCC power Bus. This is in regular use on Thousands of layouts world-wide and suitable for any layout with up to 500 feet of track work. On larger layouts it may be necessary to provide an independent second, (or more) Power Bus, possibly fed from one or more separate power boosters.

The ZTC 320 is a roll of 10 mm wide 30 meters long (dimensions are approximate) self adhesive copper strip, which can be stuck to most clean dust free surfaces providing instant adhesion. The adhesive used is an industrial based acrylic that can be used outdoors as well as indoors. The copper tape can be applied on the topside or underside of a baseboard and if required covered with scenic materials such as ballast. Bending the tape around track curves is very straightforward. Additional wires can be added, or the tape can be joined, by simply soldering the two parts together.

Full details of this and many other wiring techniques are illustrated in our DCC Expert guide on our DVD, part No ZTC 910

Decoders should be selected first on the their Stall Current Rating, then their Operational Functionality and finally on Physical Size. It is not possible to list all the decoders and locomotives here, the list is ever growing, but a quick call to our help desk on 01963 441219 should enable us to advise you quickly on the most suitable decoder for your locomotive. 

All of ZTC products are designed, assembled, tested, marketed and fully supported in the England. Not only do we design and sell DCC products, but equally importantly we use them on our own model railway layouts, so we understand our customers needs. 

Important Information

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