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| Thread ID: 101282 | 2009-07-08 05:31:00 | 50hz / 60hz question | Tony (4941) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 790047 | 2009-07-10 13:35:00 | A friend of mine is a model railway enthusiast and has just imported a couple of locomotives from the USA . He has found that some of the fancy functions (whistle, bell, lights, smoke) are only working erratically or not at all, and we wonder if maybe that the reason is the difference in electrical frequency between US and NZ . The trains run on 18v AC . So the questions are: Does this sound likely? What can we do about it? Is there some sort of converter we can put into the system (the frequency equivalent of a 240/110v transformer)? Could the fact that the power is going through a transformer be having any effect? I am neither an electrical person or a model train person, so I have no idea . Any suggestions will be gratefully received . I find it hard to believe that the trains run on AC voltage . AC may be the input to the controller but I would expect the trains run on DC other wise there is no way to put them in reverse . an AC input to the controller allows you to develop a positive DC voltage (train goes forward) and a negative DC voltage (train goes backward) . So I doubt frequency is the problem . A 110 to 18 Volt transformer will supply more than 36 VAC if plug into a 230 volt supply . I think this is where your problem arises . Whistles and bells are created using DC voltage and excessive DC (rectified from the excessive AC) may trigger protection circuits or over drive amps to give intermittent results . I would borrow or buy a multimeter and measure the AC volts at the input and the DC volts on the track . |
porkster (6331) | ||
| 790048 | 2009-07-10 22:25:00 | This has been a fascinating discussion - especially for someone who knows SFA about trains or electrics. I'm hoping to catch up with my friend this weekend, and maybe make some decisions. | Tony (4941) | ||
| 790049 | 2009-07-11 00:45:00 | I find it hard to believe that the trains run on AC voltage. AC may be the input to the controller but I would expect the trains run on DC other wise there is no way to put them in reverse. Very true. This is why all buildings with lifts have a great pile of used lifts at the top floor, since there is no way to get them down again. an AC input to the controller allows you to develop a positive DC voltage (train goes forward) and a negative DC voltage (train goes backward). So I doubt frequency is the problem. A 110 to 18 Volt transformer will supply more than 36 VAC if plug into a 230 volt supply. I think this is where your problem arises. Whistles and bells are created using DC voltage and excessive DC (rectified from the excessive AC) may trigger protection circuits or over drive amps to give intermittent results. Zounds! I would borrow or buy a multimeter and measure the AC volts at the input and the DC volts on the track. I think you may find that model train circuitry (www.siliconchip.com.au) (such as that DIY version) has advanced a little in the last few years, they are just a shade more sophisticated than a $2 shop slot car. ;) |
R2x1 (4628) | ||
| 790050 | 2009-07-11 01:06:00 | A 110 to 18 Volt transformer will supply more than 36 VAC if plug into a 230 volt supply . A 110 to 18 Volt transformer plugged into a 230 volt supply will not supply 36+ volts . What it will supply is copious amounts of smoke for the engines, but you will have to be quick to catch it . A little knowledge is a dangerous thing . . . . . . . . . . . . . . Cheers Billy 8-{) |
Billy T (70) | ||
| 790051 | 2009-07-11 08:10:00 | A 110 to 18 Volt transformer plugged into a 230 volt supply will not supply 36+ volts. What it will supply is copious amounts of smoke for the engines, but you will have to be quick to catch it. A little knowledge is a dangerous thing.............. Cheers Billy 8-{) Actually I have a lot of knowledge, I was just trying to explain things in simple terms as the originator is not "an electrical person" (his words). I would expect the regulator that follows the rectifier in the controller would stop excessive voltage to the train. More than likely now days it would be a switch mode power supply which are better at handling varing inputs. |
porkster (6331) | ||
| 790052 | 2009-07-11 08:22:00 | Very true. This is why all buildings with lifts have a great pile of used lifts at the top floor, since there is no way to get them down again. Zounds! Actually Lifts are AC Motors and are multiphase (normally 3 phase) and feeding the phases in differing orders makes them go forward or in reverse. AC motors are better in this application than DC motors. But motors for toy trains are DC. I think you may find that model train circuitry (www.siliconchip.com.au) (such as that DIY version) has advanced a little in the last few years, they are just a shade more sophisticated than a $2 shop slot car. ;) Yes sorry, measure the track DC voltage as "full speed" where the Pulse Width Modulator is putting out almost continuous DC. |
porkster (6331) | ||
| 790053 | 2009-07-11 08:32:00 | Maybe Tony should just measure what is on the rails with a multimeter. Takes 20 seconds (and $12 or so for the meter) and at least will stop our arguments :D | george12 (7) | ||
| 790054 | 2009-07-11 08:38:00 | Actually Lifts are AC Motors and are multiphase (normally 3 phase) and feeding the phases in differing orders makes them go forward or in reverse. Really? I was hoping to sell a contract for getting lifts down to the parachute club. ;) Now, explain to me how the reversing lights work in my car (without changing any positives in a negative manner). That DIY speed control is not the pinnacle of model train control -some of the more sophisticated flavours use the rails to carry a constant supply voltage to all locomotives, (and a few other bits of gear) and applies controls either by modulating the track voltage, or by other wireless means. Driving the motor at varying speeds either forward or reverse from a steady (AC or DC) supply is a trivial process. If the op's model controller uses phase shift control on an 18v 60Hz constant voltage supply, then changing the frequency buy 1/6 is possibly going to derail a few control laws. P.S. Watch out when calling model trains "toy trains" to an aficionado, they can be a bit easily ruffled. :clap |
R2x1 (4628) | ||
| 790055 | 2009-07-11 09:01:00 | More:2cents: Actually until recent years the motors for cable operated lifts were mostly DC motors powered from Ward Leonard MG sets. I believe AC motors with variable frequency inverters have now taken over to provide variable drive speed, in which case the windings are most likely switched to provide reversal. Interesting how threads develop :banana Edit: when at English Electric we needed a 200HP Ward Leonard set like..yesterday... we checked out lifts and motors as a possibility. |
Terry Porritt (14) | ||
| 790056 | 2009-07-11 09:40:00 | The most common control system with all the bells and whistles is known as DCC. This is made by several manafacturers but all are compatable as they are made to a common standard. There are books and many magazine articles available on this topic. As far as I know there are no reported difficulties in using this system in NZ. However as your friend has O gauge trains it may have the similar but non standard/ partialy compatable MTH DCS system, and I don't know anyone who uses this in NZ. However most model manafacturers have a fairly good reputation for customer service so writing should get a response. | tutaenui (1724) | ||
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