Suzie

A bit of a bonkers idea from Peco. There are very few DCC decoders that can supply the 4A+ that a PL10 requires, the popular Lenz LS150 solenoid decoders for example overload when driving PL10s and shut down.

I am not sure a SCR would work, most CDUs will continue to supply a small current after discharge that will keep the SCR turned on.

PL10 standard should be 4 Ohms giving 6A current at 24V. The TIP120, 121, 122 are 5A continuous with a good heatsink, but should be OK I guess for a short 6A pulse - I have used them to drive a matrix directly with about 30A on a good day with a short pulse and no heatsink.

The big problem will be how many of these you will be firing at once. You can make a big CDU that will fire 30A of solenoids, but you will probably be better off using the PL10W.

As for what power supply to use to drive the transistors via the buttons, probably best to derive it from whatever is charging the CDU. If using a switchmode DC PSU (best option for many reasons) use the 24V DC, if using a 16V AC transformer then it gets more complicated and will probably be cheaper to just replace the transformer with a 24V DC switchmode PSU.

The gain of the TIP121 is 1000+ so at 24V for 6A (assuming 4R solenoid) you will need a quarter watt 4000 Ohm resistor for the base (use next lower preferred value of 3K9).

Hopefully someone has a PL10W to hand and can measure the coil resistance to see how it compares.

A few questions to try and isolate the problem:-

1. What power supply are you using for your CDU?
2. What size wiring are you using for the point motors and switches and from the CDU?
3. Which Peco motors do you have and how are they fitted?
4. Which switches are you using?

There is a lot you can get wrong with solenoids.

Suzie x

What MERG modules are you using?

That Ipswich location is very odd, does it have history? The line here appears to be split in to two paralleled circuits running all the way to the site of Cliff Quay power station.

A 19V supply should be OK - most will supply the 4A required to operate a single motor at a time without shutting down. If it does shut down or you need to operate more motors at once then get a CDU as well.

Some DCC decoders (such as Zimo) have a function dimming feature that you might like to try rather than messing about with resistors.

Without the 3rd aspect you can use a steady state accessory decoder with four diodes, but for the three aspects you will need a more complex signal decoder such as the Q decoder or the Signalist SC1.

Where are the resistors on the Schneider signals? You will need to remove them to work with the SC1 and the Q decoder which drive the LEDs direct.

If the signals are wired common anode you should be able to get the 2-aspect ones to work with any steady-state accessory decoder.

The ground signals will be a bit more tricky because the indication is given by turning one of the lights off, not too bad if you don't need to show all three aspects because you can again use a standard steady state accessory decoder with some diodes, but otherwise you will need a signal decoder.

So, what aspects will you want to show?

Saw a 317 on I suspect a Walton - Colchester service, so does this mean that 360s are being moved out already in advance of the 720s coming in to service?

Looks like I might have to get in quick for a last gasp to experience first class travel in spacious 2+2 seating!

There are a couple of solutions not yet mentioned which might be more practical:-

1. If the track is used in only one direction, then the transfer section can be fed by a diode from each controller (assuming common return wiring, use a pair of diodes otherwise) to block the controllers being connected together, and no switches will be needed. Clearly if trains are being passed both ways this will not be possible.
2. Decide which controller will be the master. Use a 2-way push-button at the master position to allow the master controller to connect to the transfer section when the button is pressed. When the button is released the push-button will connect to the slave controller.

While it is possible neither of these solutions meet the original spec of 'landing light switch' operation, they will be a lot more intuitive to use in the absence of full cab control wiring.

2 hours ago, pw said:

Thanks, Suzie - you are quite right - bit of a track clean and it's working fine - I hadn't realised DCC is so sensitive in that way

 

DCC in general is not that sensitive to dirty track, just some decoders are and the default settings on some make them behave badly on dirty track - ESU are in that category unfortunately.

Excellent that you are up and running now though.

I think a lot of stuff pre-TOPS had /1, /2, /3 etc. classifications for the different variants and never a /0. TOPS numbers start at zero hence the disconnect of 33/3 being numbered in the 332xx range.

It sounds like you might have pickup troubles on the loco rather than a decoder problem.

I was assuming that the main feed was in the loop judging from where the controller was, but if not...

... the wiring will be a lot easier since the inside rail of the loop will be fed from the insulfrog point, only the outer rail will need to be switched with the frog connection, no need to use terminals 3, 4, and 5.

I am assuming that you are feeding your DCC into the loop. In this case you can use your point motor to do all the reverse switching. There is no need to buy anything else.

1. Fit insulated joiners in the outer rails of the point where it meets the loop. No need for any other insulated joiners.
2. Jumper 1-5 and 2-4 on your Cobalt IP motor.
3. Connect the DCC in from your track to to terminals 1 and 2 (DCC in) of your Cobalt IP Digital motor.
4. Connect terminal 3 (frog) to one rail of the point.
5. Connect terminal 6 to the other rail of your point.

If you are seeing a short when the train crosses the insulated gaps then reverse the wires going to terminals 3 and 6.

It is a bit complicated, but follow the steps and you should be OK.

Seeing all the old stuff going to scrap just makes you pine for comfortable seating and a proper restaurant car that made you want to go by train! Now I just go by train if I really have to. The new stock reflects that enough people really have to.

If that were the case only U+ and GND would need to be duplicated and not the track left and track right.

The 17:32 to Clacton is usually a stopper so would normally be a Dusty when I used to travel. Electric all the way so need need for a Basil.

Zimo MX638D is the £20 offering with the 21-pin plug, and MX600p12 with the PluX plug (for 12-pin, 16-pin and 22-pin sockets).

It is probably easiest to buy Zimo from CoastalDCC:-

https://www.coastaldcc.co.uk/products/zimo/all

2 hours ago, pharrc20 said:

Are those the ones close to the M6 or further away the big bulky looking ones the L6s? I believe they are finishing off the refurbishment of the L6 4ZWW line to Hams Hall.

 

Cheers Paul

It must be the 4ZWW line. Very distinctive with double insulators on one circuit with single on the other, and the twin top conductor on the single insulator side with the quads on the other two conductors.

This document refers to 4ZWW:-

https://www.nationalgridet.com/document/132516/download

Page 29 mentions work stopping for two years due to nesting birds and a few other problems! Now we know.

Went down the M6 today and the odd pylon run north of Coventry is having the lower two wires changed to twins from quads to match the top wire. Just wondering why it was not all done at the same time? Did they run out of wire? or was it an evaluation to see how the new twin on the top phase compared to the old quads on the lower two phases? There must be a story here somewhere.

Presumably the GG1s were taken out of service before the new sections of 60Hz electrification went in, else the transformers might be OK. I guess the voltage should not be a problem - there is not much difference between 22KV and 25KV, I suspect they were suitable for dual voltage 11KV and 22KV?

Would an 86 or 87 not do a good job on an electrified railway? If the wires were down nothing is moving anyway so a diesel is not really at an advantage. Might be a few 91s spare now.