MTB MP1 point motor query

[melmerby]

I don't see any advantage with inbuilt decoders on point motors.

If you don't like buying decoders, build them.

 

An Arduino will drive a Tortoise directly. Arduinos are cheap and easy to program.

[PaulRhB]

19 minutes ago, melmerby said:

I don't see any advantage with inbuilt decoders on point motors.

If you don't like buying decoders, build them.

 

An Arduino will drive a Tortoise directly. Arduinos are cheap and easy to program.

Firstly personally I have no interest in building decoders or buying the kit and learning programming when I can buy a unit that I can just connect up. I’d rather spend my modelling time on the top surface of the layout not the electronics underneath. I can make the savings there that pay for the bought in bits underneath  Just a personal choice as electronics and programming just hold no interest despite my father being an electronics engineer and my brother holding a doctorate in the field!

 

My point was really that they sell 4 and 6 output point decoders and you can guarantee you need 5 or 7 outputs! I broke it down and the cobalt usually works out cheaper at around £22 each while the Mp1 is £16 plus a decoder which works out around £10-16 each on top. 
Where I can use a dc power supply the Mp1 is nice and cheap but the DCC option allows simple route setting options with my Z21 so it’s better for the bigger layout and causes less trouble with running into points not set at shows with operators new to the layout as it sets them all. 
 

So I’ve been very impressed by the Mp1 as a compact package but it’s not always the easiest or cheapest solution if you have or are limited by certain other criteria  

[spikey]

2 hours ago, Izzy said:

Reading that the applied voltage can be varied, 9-12vDC ...

 

Hmmmm  ... 

 

I'm going to be using 4 x MP1s to switch a pair of facing three-way points via a rotary switch, and I can see it being a considerable advantage to me in this instance if I could run them off a 9v battery (viz. whatever the current equivalent of a PP3 is).

 

What odds that would be practicable?

 

Edited December 28, 2021 by spikey
to trim quote

[KingEdwardII]

29 minutes ago, spikey said:

if I could run them off a 9v battery

I've not done this - so this is only a suggestion, although it should work.

 

There are some 9.6V batteries available - either PP3 (rechargeable), or alternatively a battery pack. These higher voltage versions are likely to be able to drive the motors for longer:

 

https://www.componentshop.co.uk/9-6v-220mah-nimh-pp3-battery.html

 

https://www.batteriesplus.co.uk/acatalog/Rechargeable_9_6_V_AA_NiCd_750mAh_Battery_Pack.html

 

Another thing to consider is whether you want to switch multiple motors at the same time - this takes more current and the batteries all have current output limits. 

 

For other battery possibilities take a look at the stuff our friends in the model plane world use - 3 cell LiPo batteries @ 11.1V. There are tons of alternatives available there at a range of prices. See e.g HobbyKing.

 

Yours, Mike.

[melmerby]

23 minutes ago, spikey said:

 

Hmmmm  ... 

 

I'm going to be using 4 x MP1s to switch a pair of facing three-way points via a rotary switch, and I can see it being a considerable advantage to me in this instance if I could run them off a 9v battery (viz. whatever the current equivalent of a PP3 is).

 

What odds that would be practicable?

 

Depends on the total current consumption and amount of use. I've just measure one at 12v DC and the consumption is around 200mA for 1 second, but not moving a point!

IMHO it would be more economical in the long run if you could use a rechargeable pack. e.g. 6x AA or maybe AAA in a battery holder.

Something like e.g.

Holder:

https://www.amazon.co.uk/HALJIA-Plastic-Battery-Holder-Storage/dp/B07MFV2RW1/ref=sr_1_3?crid=EJSJ28092AW7&keywords=aa+battery+holder+6&qid=1640698860&sprefix=AA+battery+holder%2Caps%2C117&sr=8-3

Batteries:

https://www.amazon.co.uk/100-Rechargeable-batteries-PeakPower-Battery/dp/B09B2SBR6M/ref=sr_1_5?crid=2KA3T1DCSEO2E&keywords=aa+rechargeable+batteries&qid=1640698913&sprefix=AA+rec%2Caps%2C100&sr=8-5

 

[melmerby]

1 hour ago, PaulRhB said:

Firstly personally I have no interest in building decoders or buying the kit and learning programming when I can buy a unit that I can just connect up. I’d rather spend my modelling time on the top surface of the layout not the electronics underneath. I can make the savings there that pay for the bought in bits underneath  Just a personal choice as electronics and programming just hold no interest despite my father being an electronics engineer and my brother holding a doctorate in the field!

 

 

As you say, it depends on circumstances.

My railway room is at the bottom of the garden and I tend not to be there late at night as it needs heating this time of the year, however I usually have an hour or so available in my "office" in the house before bed, so can make up items there. I can do an Arduino point decoder in that time, if I have all the parts at hand.

It's where I do any experimenting/development.

Edited December 28, 2021 by melmerby

[melmerby]

3 hours ago, KingEdwardII said:

 

PS The plastic pin that needs repositioning to change the throw distance is very small - I advise that when you reposition it, you do this in some container that can catch it if you drop it. It's not a good plan to have to hunt for that pin on the floor!

You do get one spare per motor, that means you can afford to lose it but just once.

Should however be possible to fashion a replacement out of scrap.

[spikey]

Cheers gents.  Points taken (hah!).  I'll take another look at exactly how much new wiring I'd need to do and how much of a PITA it would be to run "12V dc" across the room from the accessory output of my Morley Vector Zero Two - assuming I can find enough 32/0.2 to reach the points*. 

 

If that's a goer, what would be the simplest/cheapest way for me to then drop the "12V" down to just above the voltage at which the MP1s aren't happy (that being determined by experiment)?  My objective in so doing would be to prolong the life of the motors and perhaps to cut the noise a bit. 

 

(*I'm guessing that any voltage drop resulting from a long (4 meters?) run of 16/0.2 would not in fact work in my favour)

[KingEdwardII]

1 hour ago, PaulRhB said:

the cobalt usually works out cheaper at around £22 each while the Mp1 is £16 plus a decoder which works out around £10-16 each on top. 

That's not my experience.

 

I use MP1s driven by Digikeijs DR4018 (an 8 channel decoder when driving the MP1). At current prices, using multipacks of the motors in both cases, I calculate £21.67 for the Cobalt IP motors and £19.45 for the MP1 + DR4018*.

 

You're right that it might be the case that you don't use all the 8 channels on the DR4018, but there is a flip side - the DR4018 can drive pairs of MP1s on a single channel, for things like crossovers where both turnouts need switching at the same time. I actually drive 31 MP1s with 3 DR4018s (ie 24 channels) on my layout.

 

Yours, Mike.

 

* PS: Additional information. DCC Train Automation do a bundle of a DR4018 + 8 MP1s for £149.95 which is £18.75 per motor. Sorry I missed this first time around.

Edited December 28, 2021 by KingEdwardII

[melmerby]

6 minutes ago, spikey said:

Cheers gents.  Points taken (hah!).  I'll take another look at exactly how much new wiring I'd need to do and how much of a PITA it would be to run "12V dc" across the room from the accessory output of my Morley Vector Zero Two - assuming I can find enough 32/0.2 to reach the points*. 

 

If that's a goer, what would be the simplest/cheapest way for me to then drop the "12V" down to just above the voltage at which the MP1s aren't happy (that being determined by experiment)?  My objective in so doing would be to prolong the life of the motors and perhaps to cut the noise a bit. 

 

(*I'm guessing that any voltage drop resulting from a long (4 meters?) run of 16/0.2 would not in fact work in my favour)

How about a few metres of mains cable? 1mm should be more than adequate.

 

EDIT

I haven't tried less than 12v but can try on my bench PSU later today to see how low they go.

Edited December 28, 2021 by melmerby

[KingEdwardII]

4 minutes ago, melmerby said:

mains cable? 1mm should be more than adequate.

I use 0.75mm2 mains flex cable, readily available - my longest run at the moment is ~2.5m - the voltage drop is negligible.

 

Yours, Mike.

[spikey]

8 minutes ago, melmerby said:

How about a few metres of mains cable? 1mm should be more than adequate.

 

Indeed it would - if I had any!  

 

I've just remembered that I've actually already run that "12V" DC supply over to the far baseboard in 32/0.2, so the only issue still a mystery to me is - the best/cheapest way of dropping that down gradually by trial and error until I reach the lowest workable voltage for this particular application.

 

Edited December 28, 2021 by spikey
typo

[Harlequin]

@St Enodoc put me onto LM2596 step down voltage regulators recently and now I wonder how I ever did without them!

 

They can convert any DC voltage from 3-40V down to anything between 1.5V and ~35V efficiently, i.e. without getting hot or wasting electricity. There's a little twiddly knob to set the output voltage - perfect for finding the ideal working voltage for MP1s.

 

Search for LM2596 in Google and you'll find hundreds of people selling them. They are about £2 each from UK suppliers, less in bundles. Make sure you use a UK based supplier if you want them quickly.

 

Edited December 28, 2021 by Harlequin

[bgman]

16 minutes ago, KingEdwardII said:

That's not my experience.

 

I use MP1s driven by Digikeijs DR4018 (an 8 channel decoder when driving the MP1). At current prices, using multipacks of the motors in both cases, I calculate £21.67 for the Cobalt IP motors and £19.45 for the MP1 + DR4018*.

 

You're right that it might be the case that you don't use all the 8 channels on the DR4018, but there is a flip side - the DR4018 can drive pairs of MP1s on a single channel, for things like crossovers where both turnouts need switching at the same time. I actually drive 31 MP1s with 3 DR4018s (ie 24 channels) on my layout.

 

Yours, Mike.

 

* PS: Additional information. DCC Train Automation do a bundle of a DR4018 + 8 MP1s for £149.95 which is £18.75 per motor. Sorry I missed this first time around.

 

Totally agree with the above. 

 

I recently purchased several MP1 motors and hooked them up to a DR4018 which I happened to have. 

 

I intend using this on my layout / s  and once the initial address is set the remaining motors follow in sequence. Mine is currently done using a Multimaus controller without any difficulty and is a joy to use.

 

G

[PaulRhB]

20 minutes ago, KingEdwardII said:

That's not my experience.

 

I use MP1s driven by Digikeijs DR4018 (an 8 channel decoder when driving the MP1). At current prices, using multipacks of the motors in both cases, I calculate £21.67 for the Cobalt IP motors and £19.45 for the MP1 + DR4018*.

 

You're right that it might be the case that you don't use all the 8 channels on the DR4018, but there is a flip side - the DR4018 can drive pairs of MP1s on a single channel, for things like crossovers where both turnouts need switching at the same time. I actually drive 31 MP1s with 3 DR4018s (ie 24 channels) on my layout.

 

Yours, Mike.

 

* PS: Additional information. DCC Train Automation do a bundle of a DR4018 + 8 MP1s for £149.95 which is £18.75 per motor. Sorry I missed this first time around.

Mike I agree it tends to work out better on larger or fixed layouts but as mine are all smaller or multi section portable I rarely get more than 6-7 points on a board and mostly 3-4 so the economics start to fall apart with extra connectors and additional cross board wiring

I would use them if it works out cheaper but so far the cobalt has edged in cheaper in most cases. As I said above it varies on the application so you just have to figure out the costs each time. On the modules though the mp1 has made more sense financially and space wise  

[KingEdwardII]

6 minutes ago, PaulRhB said:

mine are all smaller or multi section portable

Paul, 

 

Fair enough - your situation is different and so the Cobalt IPs make make more sense for you. I just wanted to be sure that folk reading this thread had a clear idea of the relevant costs - everyone needs to make judgements based on their circumstances.

 

Yours,  Mike.

[RobinofLoxley]

4 hours ago, KingEdwardII said:

If you open the mechanism, it becomes clear how the MP1 works. It is easy to open the package with some jewellers screwdrivers - and you actually need to do this if you want to change the throw distance.

 

Inside there is a neat assembly that converts the rotary motion of the motor into a linear motion that moves the metal pin. The assembly has a small plastic pin which can be positioned at one of 3 different radii on the circular component attached to the motor - and it is these radii that dictate how far the linear slider moves between the endpoints (ie. 3/6/9 mm). A neat and simple design. Once the end point is reached, the linear slider is basically fixed in place by the positioning of the plastic pin, so that the metal pin driving the tie bar is unmovable and keeps the tie bar in place.

 

The motor rotates the circular component through 180 degrees and there are switches that detect each end of travel and cut the power to the motor once the end point is reached. So if the end point is not reached, the current is still applied to the motor - e.g. if something jams the turnout. You get a buzzing sound if this occurs. I don't know if the motor would burn out eventually if the current is left on, but I do know that the motors don't burn out quickly - I've had some left on for up to 10 seconds or so when there was a problem. They take a fairly low current, so would probably take quite some time to overheat.

 

Yours,  Mike.

 

PS The plastic pin that needs repositioning to change the throw distance is very small - I advise that when you reposition it, you do this in some container that can catch it if you drop it. It's not a good plan to have to hunt for that pin on the floor!

I had already done all of the above. When I was looking at them I bought 2 to play around with. That's when I found that when set at 3mm, the motor would not set a Hornby 8077 or 8078 exactly in position at both ends of its travel, one blade would always be left stcking out enough to derail an oncoming train. Hence I set (well, left, all of mine at 6mm). I had more trouble wiring the DR4018's that controlled them and then getting the Dr4018's to listen either to the Z21 or its maintenace app. (Thanks to Iain M).

I found on setup if the motor was facing the 'wrong way' it would buzz when powered but flipping the turnout control to the opposite position would stop that. Once the pin travel was set up centrally with the tie bar, no more buzzing. I found it safer as I said to start them up with the two screws loose, observe the travel, and fix the pin from that. Got about 20 working at the moment, and while they havnt had that much use while Im layout building, no problems yet.

[RobinofLoxley]

1 hour ago, Harlequin said:

@St Enodoc put me onto LM2596 step down voltage regulators recently and now I wonder how I ever did without them!

 

They can convert any DC voltage from 3-40V down to anything between 1.5V and ~35V efficiently, i.e. without getting hot or wasting electricity. There's a little twiddly knob to set the output voltage - perfect for finding the ideal working voltage for MP1s.

 

Search for LM2596 in Google and you'll find hundreds of people selling them. They are about £2 each from UK suppliers, less in bundles. Make sure you use a UK based supplier if you want them quickly.

 

So do you have one per point motor ??

[RobinofLoxley]

1 hour ago, melmerby said:

You do get one spare per motor, that means you can afford to lose it but just once.

Should however be possible to fashion a replacement out of scrap.

The suppliers tend to have replacement pins and other losable bits bagged up for people like you and me, they will send them to a good customer on request I have found.

[melmerby]

1 hour ago, Harlequin said:

@St Enodoc put me onto LM2596 step down voltage regulators recently and now I wonder how I ever did without them!

 

They can convert any DC voltage from 3-40V down to anything between 1.5V and ~35V efficiently, i.e. without getting hot or wasting electricity. There's a little twiddly knob to set the output voltage - perfect for finding the ideal working voltage for MP1s.

 

Search for LM2596 in Google and you'll find hundreds of people selling them. They are about £2 each from UK suppliers, less in bundles. Make sure you use a UK based supplier if you want them quickly.

 

Last time I metioned a buck convertor on RMWeb I effectively got shouted down on why not to use them.

However I have used several when making Arduino projects to reduce my (rectified) 15vAC bus down to a voltage suitable for the Arduino & peripherals without a problem

 

Mine cost me £3.63 for 10 plus P&P from Aliexpress, gone up a fraction. HMRC might want a bite now!

https://www.aliexpress.com/item/4000259403990.html?spm=a2g0o.9042311.0.0.27424c4dY7Qdes

 

[melmerby]

2 hours ago, spikey said:

 

Indeed it would - if I had any!  

 

I've just remembered that I've actually already run that "12V" DC supply over to the far baseboard in 32/0.2, so the only issue still a mystery to me is - the best/cheapest way of dropping that down gradually by trial and error until I reach the lowest workable voltage for this particular application.

 

I have just tested one on my bench supply (regulated DC), on it's own without a point to operate.

This time I tried the current with an analog meter (Avo 8) and it registered about 120mA at 9v.

At 9v it isn't particular strong but should be OK with a free moving point, with 12v it is perfect and I would recommend that if possible.

At 8 volts it would just about operate but could be stopped with little force, 7v it wouldn't move it at all.

Personally I wouldn't go below 9v as the strength drops off dramatically below that.

[Harlequin]

40 minutes ago, RobinofLoxley said:

So do you have one per point motor ??

In fact I'm not using them to power any MP1s at the moment but they are rated at 3A continuous output if you fit a good heatsink to them so they should cope with about 20 MP1s operating at the same time. Since continuous operation of MP1s is unlikely then the heatsink will probably not be required anyway.

 

Where I have used them is:

1. To convert 15V down to 12V to power a Raspberry Pi (with a heatsink!).
2. To power a Dapol signal (more to be added later).
3. To power an original Dapol water tower, which would literally explode (from the reports on here) if given more than 9V. This was apparently due to a component that was not within the specified range.

(I think my MP1s are running at 12V - from a MegaPoints board.)

 

Edited December 28, 2021 by Harlequin

[Izzy]

3 hours ago, spikey said:

 

Hmmmm  ... 

 

I'm going to be using 4 x MP1s to switch a pair of facing three-way points via a rotary switch, and I can see it being a considerable advantage to me in this instance if I could run them off a 9v battery (viz. whatever the current equivalent of a PP3 is).

 

What odds that would be practicable?

 

I currently use ‘hacked’ servos for point/signal movement and initially powered them using re-chargeable AA’s. Even with spare packs I found it a fag having to change them, and especially if they ran down in the middle of an operating session. So I would suggest the 12v dc supply is a better route. 

 

I re-worked them to be powered of the DCC bus (at 5v) using a step-down converter similar to the LM2596 mentioned that takes both AC/DC input. These are made by Vellemann, K1823, ( LM317) but are only 1amp. Output from 1.5v upwards, adjustable with a little potentiometer set with a screwdriver. A bit more expensive than others mentioned. I have four on different layouts and they work without issue. No heat because the motor current draw is not continuous as with the stall types. They will power several at once, pairs for crossovers and so on.
 

Not sure if your Morley has short circuit protection etc. but if so you will need to arrange things so the track power can be switched off when a short happens, points set wrong (!) etc. so there is the juice to power the motors to change them. Unless the 12vdc is off a controller accessory bus of course. 

[spikey]

1 hour ago, melmerby said:

... This time I tried the current with an analog meter (Avo 8) ...

 

Oh I say!  I do hope you have it in its proper leather never-ready case.

 

MIne used to belong to a chap called George Percy Oliver.  He had his initials branded into the leather

[melmerby]

19 hours ago, spikey said:

 

Oh I say!  I do hope you have it in its proper leather never-ready case.

 

 

Nope, I don't think we had leather cases with ours at work as they were always on the bench. They probably did when new but were soon discarded.

At one point I had the privilege of actually repairing and calibrating them. Good old British built like a tank craftsmanship. It's now about 45-50years old.

Mine is an 9 mkIV, at least that's what it says on the movement. It's got an greeny grey plastic case with the usual black front panel with icons rather than the words as on the 8. It must have been withdrawn from use in the late 1980s (?)

 

EDIT

I worked for that bloke

 

Edited December 29, 2021 by melmerby