Before I get all fired up crazy and make my own PCB board I would like to wire this all up to get a feel for what I am doing and its size and how it will work and fit in a loco. What is a good make shift through hole board material. I realize I will be making wired connections on the back side which is fine but would still like to have something rigid to mount it all too. I see they make prototype boards with lots of holes and they are pretty cheap but what about like plexiglass, I have lots of like 1/16" thick plexiglass. I figured if there was a make shift material then I could try different configurations and what not without wasting and cutting up the circuit boards.
Devon - I have used acrylic (PlexiGlas) for some prototypes - works well except when the soldering iron gets too hot!
Before doing a circuit board I would spend some time with the test unit to make sure it is reliable over time - please keep in mind that I was just experimenting - I did not do any extended tests under load - all sorts of bad things could crop up!
dave
Devon Sinsley said:
This one I figure I would keep simple and run say a 11.1v LiPO or Li Ion attached to a plug that is hard wired to the screw terminal and then I can disconnect and charge the battery remotely or swap them out when dead to keep the battery size as small as possible say 800 mAp.
Once I am convinced I wont blow up my controller or burn my house down I can play with building another, reducing the voltage of the whole system down to 4v for the Tamiya motor.
Thoughts, ideas, mistakes, criticism, suggestions?
OK. One comment that you will instantly appreciate on your second install - pick a standard plug /socket for charging onboard batteries.
All my electric locos use a 5mm power plug from RS, and my steam engines use a 5.5mm plug (te latter use 4.8V batteries, while the former are anything from 14.4 to 22V.) I am not sure what you can get your hands on these days. Ah - Radio Shack still exists:
You will notice that the socket (jack) has a switch. Many battery/rc guys like me use it to disconnect the electronics when you plug in the power plug from the charger. Here’s how I wired 2 x 7.2V packs for a 14.4V Bachmann ten-wheeler:
My EBT #15 RY Models loco has dual 11V Li-ion batteries and dual sockets/jacks for power, with a terminal block for wiring the batteries and charging. I have a Tenergy smart charger for Li-ion with the appropriate plug on a connector to the charger.
What about a 2amp circuit breaker between the Battery and the switch, necessary?
There’s a thing called a “polyswitch”. It instantly disconnects the circuit between its two poles when the current is exceeded. You can use them in parallel for currents higher than 1A. I bought 50 @ 1 amp some years ago and my locos have them (see the s/s switch in the circuit below.).
Devon Sinsley said:
Before I get all fired up crazy and make my own PCB board I would like to wire this all up to get a feel for what I am doing and its size and how it will work and fit in a loco. What is a good make shift through hole board material. I realize I will be making wired connections on the back side which is fine but would still like to have something rigid to mount it all too. I see they make prototype boards with lots of holes and they are pretty cheap but what about like plexiglass, I have lots of like 1/16" thick plexiglass. I figured if there was a make shift material then I could try different configurations and what not without wasting and cutting up the circuit boards.
I use Radio Shack PCB packs. This small one has holes ringed with solderable copper. You can cut it to size.
https://www.radioshack.com/products/grid-style-pc-board-750-holes?variant=5717554309
On this photo, there is an Aristo mini-recvr, an accessory board with lots of reed relays, and another PC board that I made with more reed relays soldered to it. It all fits inside the boiler of an old 1/24th Aristo C-16.
Not a bad call on making sure from the get go that I use the same onboard charging jack. I already have one on the 2-6-0 so I will have to make it standard. I also want all the locos batteries to have a plug so they can be removed easily when and if the need arises so will be standardizing that as well.
David,
Does it matter which side of the relay the coil is feed from or are the LED + and Red interchangeable? The coil isn’t directional is it?
Now as I am learning this brings up a second questions about relays. We are using a common positive because we are using the same voltage to power both the relay coil and the track/motor. In the case where I want to run a 3v motor could the coil be ran at lets say for arguments sake at 12v and the motor lead voltage at the 3v coming into the relay? Could the voltage be stepped down from supply voltage to 3v with a resistor before entering the relay. The coil is doing the switching work right and the incoming power is just simply providing the current to run the motor.
Devon - most relays don’t care about polarity on the coil - I have run into some that do so I always test a batch before using them to see if they care.
The controller is using PWM (Pulse Width Modulation) to vary the output to the LEDs is it designed to operate - it doesn’t really vary the voltage but the ratio between on and off time (Google PWM for more info) - You could try a resistor but you are better off to find a lower voltage relay and try to match them to close to the same required voltage.
dave
David Bodnar said:
You could try a resistor but you are better off to find a lower voltage relay and try to match them to close to the same required voltage.
dave
Well that would be way simpler
Devon Sinsley said:
Not a bad call on making sure from the get go that I use the same onboard charging jack. I already have one on the 2-6-0 so I will have to make it standard. I also want all the locos batteries to have a plug so they can be removed easily when and if the need arises so will be standardizing that as well.
Many batteries come with a Tamiya connector installed, so you can just plug them in to your r/c car (!) I bought a few connectors and installed them on my terminal strips so the batteries just unplug - once you take the tender apart. I haven’t needed to do that very often as the electronics are under the coal in the center.
I will have to see what the battery comes with that I ordered and go from there. I have seen what is called a JST connector and they are cheap JST plug 2.49 for 10 pair at Banggood.
With the charger I got I have many connector options also so could use one of the leads and wire one of these on. Then I can charge either in the loco with a jack plug or out of the loco with one of these. As well as change out in need be.
Devon - I use lot of the JST connectors - I have an overview of such connectors on my web page:
http://www.trainelectronics.com/Articles/Connectors/index.htm
dave
NOTE A polyswitch does not really ‘disconnect’, it is a fast acting resistor that increases its resistance with overcurrent .
Circuit breakers and fuses disconnect but these need to be reset or replaced, a poly switch will cool off and lower its resistance back near 0 ohms if the overload is removed (can be a current overload, not just a short!!).
Also note that when using relays you need a diode to get rid of the back emf (usually placed across the coil)when turning the coil off and I like using the ones with the built in diode (diode is in series with the coil making it polarity dependent) as it is less work/wiring for me to do.
I would be very grateful if some kind soul could point me in the correct direction for buying JST male & female inline connector cables, the same as Aristocraft uses at the ends of their locos.
Ok, like these?
Try these on EVILBAY
search for JST 2.54 SM 2-Pin Connector plug Female & Male with 10cm Wires Cables
twenty sets for $4.50
Bill
Thank you gentlemen. With your help I found what I need.
Tony, et al:
Be advised, that which side of those JST connectors is red and which is black is not necessarily consistent among the various suppliers. I started with using them to match the polarity of the Aristo battery connection, and find now and then batteries, and other connectors with reversed red and black. So just be aware of polarity and color.
Regards
Jerry
Thanks Jerry.
I have been using them for years getting them made up here in Australia. Mine were made to match those fitted to USAT locos.
My local supplier has now retired so a new source was required.
They are easy enough to swap wire places as needed.
Ok, this is all very thought provoking.
Could you power a second relay here to perform another function?
For example, turn it on and off in the same way but use the blue channel to power the headlamp in one direction on one side of the switch and a reverse light on the other.
So DYI 1 is (red) relay on, (green) forward motion control, (blue) headlamp on(dimmable)
DYI 2 is (red) relay off, (green) reverse motion, (blue) taillights
And seeing how you would most likely decrease speed to zero in either direction before changing direction and could dim the lights off, DYI 3 might be used to perform some other function rather than all stop.
What that function would be I have no idea but I like having open options.