flockandroll

6 minutes ago, Edwin_m said:

You could just use a car battery, as these can supply huge currents.  According to Wikipedia the cigarette lighter socket is likely to be rated at 10 amps.  

 

 

Thanks, but that is not the solution for me...

Quote

2.25 *3 = 6.75W. That is a big resistor, or a matrix of smaller ones. 

Thanks.

Thanks the 100 ohm variable resistor I have is 5W so not quite up to the job.

I guess the bigger power supply will be easier.

I have a 100 ohm variable resistor, could I use that and an ammeter to check the current is under 3A ?

Hopefully the heater will still put out enough heat!

50W with 12V would be 4.17A

R =V/I

so R = 12/4.17 =2.88 ohms

But I need to be a little under 3A, so total R = 12/just less than 3 = just over 4 ohms,

so I would need to add a resistor of about 1.25 to 1.5 ohms in series with the water heater.

Is any of that correct?

I can't remember what resistors I have...

Quote

Not necessarily - you could put a resistor in series with the heater to work on your power supply. Of course your heater wouldn't be 50W any more but it might be warm enough.

I did wonder, but is it really that simple? And what would the maths be?

Thanks.

So I guess I need to upgrade my power supply.

Mathematically 12A 5A 60W should be sufficient. Will it be sufficient in practice?

https://www.amazon.co.uk/COLM-Adapter-100-240v-Switching-Adaptor-12V-5A/dp/B07HRLGV3S/ref=pd_lpo_sccl_3/261-2754844-5307136?pd_rd_w=TiIAQ&content-id=amzn1.sym.448aab69-6fff-42b9-9d7a-f6325052a6f6&pf_rd_p=448aab69-6fff-42b9-9d7a-f6325052a6f6&pf_rd_r=2KTQJSYVF2SR9F4FEBYX&pd_rd_wg=p3WPg&pd_rd_r=14150e46-7d8e-48c1-8fb9-7a28f44b9e0a&pd_rd_i=B07HRLGV3S&th=1

The next one up is 12V 10A 120W, which seems rather a lot of power!

https://www.amazon.co.uk/COLM-Switching-100-240v-Transformers-Accessories-12V-10A/dp/B07J43TMYW/ref=pd_ci_mcx_pspc_dp_d_2_t_1?pd_rd_w=8VGBm&content-id=amzn1.sym.8db49f41-2d78-4c1c-bc3b-fb9e44b9efb4&pf_rd_p=8db49f41-2d78-4c1c-bc3b-fb9e44b9efb4&pf_rd_r=2W566NZ5ERGF892C0ARD&pd_rd_wg=H7Ki9&pd_rd_r=c2f02bc8-f47f-4ec9-af30-29f421ae9698&pd_rd_i=B07J43TMYW

Both come with a nifty adapter at the DC end so you can easily connect + and - wires, and I would hope to get some modelling use out of it at some time.

So really, I just want to make certain in the real world 12V 5A 60W DC supply will be ok for the 12V 50W heater (it's 20% extra so it must be?). Thanks

I need to do a science experiment like this:

Measuring the temperature of melting ice experiment - Temperature changes and energy - Edexcel - GCSE Physics (Single Science) Revision - Edexcel - BBC Bitesize

https://www.bbc.co.uk/bitesize/guides/zpjpgdm/revision/8

I have a 12V power Supply that is rated at 3 amps.

I have a miniature water immersion heater that is “12V, 50W”.

In terms of current, voltage and power, can I safely use the power supply to power the heater? (In terms of wires and connections it is fine.)

When I was much younger, I used to think that somehow, “Oh no, 50W at 12V, it will draw over 4 amps to get that 50W at 12 volts, so something will overheat and go pop or worse”.

But now I also think, “There’s only a maximum of 3 amps available, and the heater won’t be able to magically get more than 3 amps, so all that will happen is the heater will run with only 36W, so it will not get as hot, but everything will be safe, and nothing will break”

Which view is correct?

The circuit will look something like this:

Thanks!

http://Look North (East Yorkshire and Lincolnshire), Evening News: 16/01/2024: www.bbc.co.uk/iplayer/episode/m001vgx8 via @bbciplayer

from 24.05

Tonight's BBC Look North for East Yorkshire and Lincolnshire, report on Market Deepening Model Railway Club about it's many youngsters. BUT begins by saying how the hobby is getting older and at risk of dying out (IIRC)!

Look North (East Yorkshire and Lincolnshire), Evening News: 16/01/2024: www.bbc.co.uk/iplayer/episode/m001vgx8 via @bbciplayer 

from 24.05

Feeling a bit more confident with it now. Thanks all

So this way does actually change CV1 but "at arm's length" as it were, without using the "nuts and bolts" method of actually going into each CV as it were? And having to alter CVs to enable long addresses?

So going back to the locomotives that have CV1 = 3, I can do that for all of them, they will respond individually to themselves (if that makes sense?)?

2 hours ago, Gray69 said:

It is easiest to use the '# Program address' setting in the CV programming section of the Z21 app to change the CV. With this you can choose 667 and 7818 without issues. Don't worry about CV1

Like this...ah!

So I have the knowledge to change CV1 to a short address, and the knowledge to rename the loco in the app. 

Not sure if it will continue to irritate me that for instance CV1 = 66 and the name is 667, 

and CV1 = 78 and the name is 7818

3 hours ago, Gray69 said:

When you are new to DCC, it can be overwhelming

2 hours ago, RAF96 said:

Confused - you will be...

Indeed!

So I have one loco that used to be CV1 set to 3, but I changed it to 37,

two locomotives that have CV1 set to 3, and a fourth one that I expect also has CV1 set as 3.

Having one of these CV1 = 3 locomotives on the track, I can control it with the Z21 app using the pre-installed loco 3

(see, I previously changed the name to Alex)

So, one question is, if I put two locomotives on the track each with CV1 = 3 can I control them independently, or will they both respond ? I would have said that they will both respond, but now I am not so sure...

(Should I re-title this thread as "Understanding and using Z21 black and loco addresses - a basic introduction"?)

12 hours ago, Steamport Southport said:

Use some good quality tissue paper

4 hours ago, cypherman said:

Make sure the paper is acid free wrapping paper such as this. 

KAPCO 100 White Tissue Paper MG Acid Free Sheets (20 x 30 inches) for Arts & Craft, Decoupage, Packing, Moving, Removal, Packaging Material for Clothes, Shoes & Storing Fragile Items (500mm x 750mm) from Amazon

Thanks!

That's good to hear: I already have some acid free tissue paper I bought to wrap up some old Hornby and Triang locos I was given. But never thought about using it to replace the film

What’s that you say? You tear off and throw away the tissue paper wrap around the box 🫣 <faints>

I have bought quite a few second hand wagons with the boxes still wrapped up

This is a nearly new Rapido Hunslet 16 inch. Is the loco paint likely to be damaged?

Especially if I have to post it back to Rapido? Don't know how I lost the film. It feels different (more filmy!) than for instance a plastic bag, so not sure if it is OK just to replace it with plastic from a bag (as you read about bubble wrap and some foams reacting with models over time)?

(This seems like a "first world problem" but there you go, I'm prone to being a bit of a worrier.)

Thanks

So I should explore how to change to long locomotive addresses before I do this, so I only have to do it once.

Thanks

If it's any help, something similar seemed to happen to me. Completely shutting down my phone, then turning it on again fixed it. Sorry if you have already tried this.

Taking the Hunslet off the track, and putting a Planet Industrials Victory on, using the app for loco 3, everything is fine for that loco. So it is something I have (or have not done) with the Hunslet.

I am new to DCC, this could be my second newbie error. I wanted to change the loco address from the default 3' to the actual (builder's) number of the loco, 3716.

Watching a couple of YouTube videos, I went into the vehicles part of the phone app, added the loco and picture, changed its number to 3716. But now in steering, no function keys are displayed, just speed and direction and a picture, on the right. The left side of the screen where the functions used to be displayed is now blank.

So I thought,  "Oh, I need to reprogram the decoder on the program track. So switch over the connector on the back of the Z21, put the loco back on the track, read CV1 and it is set to 3. So I change it, I wanted 3716, but I settle for 37 for now, as 3716 is a long address, and sticking to a short address is easier for now. Reread the CV, and yes, CV1 is now 37.

Back to vehicles, basic information and change loco address fro 3716 to 37.

Loco off track. Change over green plug to main track loco back on track. Select loco in steering, still no function keys visible.   

I can control speed and direction, but no functions (that is to say, firebox flicker and sounds). I have added loco to the WLANmaus, and I can control the speed and direction only. Before I started changing the address, I could control sounds and turn firebox flicker on and off. The loco is a Rapido Hunslet 16in Alex with factory fitted sound decoder.

How can I get the functions back please?

Thank you, it now seems to be working!

This is the router that came with the Z21 🙂

Thanks!

I will have another go in a minute.

Doubting myself/everything a little now, but the password is what's printed under the router, isn't it?

Hello, I hope everyone is well.

I am a new user of DCC, have briefly used my Roco Z21 black with one loco and the app on my phone, so far.

I also have a new WLANmaus (because I thought I might like the more tactile nature of it).

Setting up and connecting to the Z21 network was going fine, until I finished entering the password... and then realised that you need to press each key multiple times to enter a number (except for 1 and 0 where only one press is needed). And therefore the password I actually entered was, of course, incorrect.

And at this point, I and the WLANmaus are stuck. Can't even turn it off without taking out the batteries! And turning it on again, still stuck at the same place. I was able to get into the menu, search for networks, find the network, but not able to re-enter the password, it just seemed to remember the wrong one, so still stuck! 

I tried to do a factory reset, the maus turned off. But when turned on again, straight back to being stuck.

Please can someone tell me how get the maus to forget the wrong password / let me enter the password correctly?

Thanks!