Converting Accucraft K-27 to battery r/c

Greg Elmassian said:
Perhaps the calibration and selection of power curve needs the motor attached?

Greg
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I think you will find it is more to do with the 'servo pulse width', and stick settings on the Tx, and what comes out of the Rx..
You can set centre-off, or low-off, as well as telling it full-on / forward and full-off / reverse settings.
 
Greg Elmassian said:
Tony, I looked for any instructions on the Fosworks site for his ESC, but no documentation was found.

I'm just curious to learn, so if you can point me somewhere I would appreciate it.

Greg
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Hi Greg.
Fosworks instructions are a bit light on the ground.
They are included with an ESC and are minimal but adequate.
I made up my own for the 160 ESC.
COBRA 160 ESC

Yes Greg. The motor(s) do need to be connected so you can check the ESC is working OK.
The LED on the ESC indicates reliably what is going on.
You get three seconds to start the calibration process after the rx binding/re-linking has taken place.
 
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I have only been stocking the COBRA-160 ESC for a few months and not done that many installations. So I could not say for sure that not connecting the motor is at fault as I have always connected the motor anyway.
BTW. Not that it really matters but the COBRA-160 is only 30 watts continuous.

Fosworks are now offering a 100 watt version (# 260) of the Centre OFF ESC.
They are also making a 100 watt Low OFF version for me which should be ready soon.
 
Greg Elmassian said:
So, it appears he tried to do the binding and even the calibration without the motor connected, in your opinion could this be the issue?
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Correct Greg. But where does it say you need to have a motor connected ? Tony, essentially I have the same basic instructions supplied to me as you issue. There is no mention in your link of a motor needing to be connected, just the instruction "turn the loco on". As I have everything self contained, bar the motor, in the tender then I have "turned it on" :)

As previously said my only experience with an ESC is a Mac5, that did not need calibration or offer anything other than a standard power profile. I don't understand the need to actually have a motor attached when carrying out these actions other than to provide a physical "proof" in the absence of a multimeter. The calibration is between the ESC and the Tx alone to establish the Tx's throttle values, the binding process is purley to establish a link between the Tx and Rx and the power curve setting the voltage delivery parameters that only exist within the ESC. The motor is just a dumb bit of kit (a bit like me) that consumes and reacts to whatever power the ESC delivers to it. Or am I missing something here ?

When I plug my Train Engineer controller into my line each spring I do not have to calibrate every time I put a loco on the track. Yes I had to bind the handset to the controller when I first used it but I did not have to calibrate it nor have a loco on the track when I did. You can see my confusion. If this is an essential element why is this not in the manual. I shall seek clarification from Fosworks. Max
 
That there is nothing in the instructions about needing the motor to be connected is a good question to put to Steve Foster.
I just assumed that was what was required for any installation so I did it.

If calibration is not done correctly it would be highly probable that the ESC "brain" is not actually telling the output to do anything. Hence no output.
 
Have to say that much of this is a little beyond my knowledge. All of my I stalations have been pretty simple in that I have not used other than MLS / Fosworks Cards or a DCC Chip on the DCC System. Though I do have a couple of Aristo Systems with differing Sound Cards. I have however had to do some Fosworks Binding and it is indeed a little bit fraught in that you really do need to nail it within a very short time or it will not take. Steve’s (Fosworks) you tube demo shows how quick you need to be. I have mostly had dual systems from Fosworks and in the past Spoerer that were pre bound.

As for Testing sans Motor attached, pretty sure that I have done this but with Max’s more complex installation I wonder if that may be the problem? Perhaps a spare Motor attached to try things out?
 
I probably started the wobble on this - it's simply that I have never bound an Rx of any sort without the motor connected.

Having said that, it wasn't a positive decision of something that must be done, it's simply that for my needs I only ever needed to bind the Rx to the Tx to make the motor work.

It therefore occurred to me, in the world of troubleshooting, that it was worth a try. As I mentioned earlier, you don't know the thinking behind the ESC programming and I suspect that, given the way most wiring circuits are shown, much of the thinking is around having everything in one place.

I do have one loco with the ESC in the tender, but I still bound the Rx / Tx with the loco hooked up and this is the loco with the Peter Spoerer electron ESC :nod::nod:
 
Calibration is necessary between Tx-Rx-Esc because there are a couple of 'standard' pulse-widths for the signal to drive a servo (ESC in this case)..
The amount of 'travel' can also vary (how far the servo is told to move, from one extreme to the other)

The Cobra 3, not only has 'inertia' (which is user-set) but allows you to set the ESC for low-off, and even to reverse the direction.

I to have been looking at trying to improve the instruction-wording, but it is not high on my priority list..
 
Ok, had a word with Steve at Fosworks this morning. He confirms that the Cobra ESC does not need a motor attached to be calibrated with the Tx nor to have the power curves adjusted. It also makes no difference which way round you do these operations. Just make sure you do the calibration if you want it to run ( I think Steve mentioned it should work "out of the box" without the calibration but the values would not be optimised for the Tx). The slow blinking LED on the Cobra confirms all is ok and as It should be. Steve has agreed to look at all the components, there was an issue with one of the Pico switches too, to see where the problems may lie.

Now, when I came to uninstall all the bits and pack them up I noticed as I was packing that the white lead (grouped with the red and black) from the Cobra ESC to the Rx 3 had become detached from the ESC's board. This might be the root cause - but when I look at the picture of my installation in post #73 it looks secure and in place, as it did when I was fault finding. Did this happen when I took the installation appart or before ? Could a weakened joint cause this issue ? I haven't moved any of the components after installation or detached the wires from the ESC to the Rx3 at any point (they were supplied with the Pico switches in place in their assigned positions - all the boards were firmly fixed in position too. Curious. Still does not explain the Pico Switch issue though. Max
 
maxi-model said:
Ok, had a word with Steve at Fosworks this morning. He confirms that the Cobra ESC does not need a motor attached to be calibrated with the Tx nor to have the power curves adjusted. It also makes no difference which way round you do these operations. Just make sure you do the calibration if you want it to run ( I think Steve mentioned it should work "out of the box" without the calibration but the values would not be optimised for the Tx). The slow blinking LED on the Cobra confirms all is ok and as It should be. Steve has agreed to look at all the components, there was an issue with one of the Pico switches too, to see where the problems may lie.

Now, when I came to uninstall all the bits and pack them up I noticed as I was packing that the white lead (grouped with the red and black) from the Cobra ESC to the Rx 3 had become detached from the ESC's board. This might be the root cause - but when I look at the picture of my installation in post #73 it looks secure and in place, as it did when I was fault finding. Did this happen when I took the installation appart or before ? Could a weakened joint cause this issue ? I haven't moved any of the components after installation or detached the wires from the ESC to the Rx3 at any point (they were supplied with the Pico switches in place in their assigned positions - all the boards were firmly fixed in position too. Curious. Still does not explain the Pico Switch issue though. Max
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or could it be ..................... :mask::mask::mask::mask: Piggy Malone and Charlie Farley
 
The white wire of the three plugged into the Rx is the signal wire from the Rx.
If it is not connected the ESC cannot receive instructions from the Rx to "run".
It is the first time I have heard of such a fault in a COBRA-160 ESC.
 
Tony Walsham said:
The white wire of the three plugged into the Rx is the signal wire from the Rx.
If it is not connected the ESC cannot receive instructions from the Rx to "run".
It is the first time I have heard of such a fault in a COBRA-160 ESC.
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I figured that one as soon as I saw it Tony. Doh ! A bit embarrassing :blush: that I did not spot it till it was off the board and being packed up and the fact I probably caused/aided in causing the problem by possibly not handling the card properly along the line. Anyway best to get it checked and re-soldered and the recalcitrant pico switch likewise.

The loco runs fine plugged into the TE but I've noticed the headlight and cab light are not working (need to get some replacements for the classification lights too) despite fitting a replacement voltage controller (again kindly supplied by JohnS). More fun with a multimeter. I also notice I'd plugged the the wires for the tender mounted rear light into the 18v supply rather than the variable voltage supply at the bridge rectifier input. I hope Steve will be understanding :wasntme: Live and learn as my dear father used to say. Max
 
Bits all returned from Fosworks. As well as fixing Steve had kindly taken the trouble to mark everything up so there can be no issues with me misconnecting things (Whisper it, I never noticed till he told me). Wired it all back up and tested it without the loco plugged in, everything fine and dandy. That is till I plug the loco in - bells and whistles start sounding randomly :banghead: I get over my fear of resetting functions on the Sierra card (it really is quite straightforward) but essentially nothing goes round the problem. Quick call to Steve at Fosworks and I arrange to take it up to the Peterborough show as he has kindly offered, without any pleading from me, to have a look and see what the problem might be. You'd think he had better things to do that day.

Solution found - seems like there is some interference from the motor causing the Sierra card to think it is getting "triggers" for its bell and whistle functions. Steve applies a "choke" to the cables from the motor and all is well. Phew ! :whew:

Get home and next day go to switch it on for a run on my line - it's dead as a Do-Do. Would you believe it the a small wire from the rear light had become detached in transit and appears to have shorted across the output terminals of JohnS's PWM to Linear converter. Result - blown main fuse. Panic and cold sweat ensues :sweating: Quick e-mail to Fosworks (on a Sunday) gets a swift reply same day and the promise of 3 & 5 amp fuses. They arrive the next working day. Pop in a 3 amp, as advised by Steve, and all is well. The Fosworks "quick blow" fuse has done its job and protected all those valuable cards and hard work. Another phew :whew:

So now I've got some time off so I'll finish recommissioning the line for the new season and hopefully be able to sit back and relax to the sound of my K-27 chuffing around merrily. Hope the neighbours will be out :giggle: All around excellent customer service from Steve Foster at Fosworks - Big thank you. Max

P.S. I think I found the pickup connection from the drivers to the loco's electrical circuit. Checking the wiring for the head and classification lights, at the main terminal block under the firebox, I noticed an extra tag on one of the R/Hpair of terminal posts. Gave it a gentle tug and realised it was not connected to he lighting circuit nor the motor wires - QED it must be how the power is getting from the drivers to the rest of this loco. din't bin it but isolated the now detached tag with some shrink. So, the and tender & loco body should now all be isolated from any inputs from the track - famous last words.
 
Great news Max....fingers crossed for you!... Looking forward to the video of her riding your rails
 
And finally.............


and


Well it seems to all run ok now. It developed a tendency to separate from its tender when testing light engine, so I slightly cranked the drawbar. Seems to have fixed the problem.

Despite locking out the voltage control of the Sierra's bell sound (and by default the grade crossing whistle) - both sounds should now only operate when triggered from the Omni2 tx by a dedicated pico switch, I still get the odd random activation of the bell (listen to the end of the 1st video). You can't have everything I suppose. I'll sit back and enjoy it for a while and fiddle with the settings some more to sort it later. Max
 
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