Converting Accucraft K-27 to battery r/c

PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
23,179
405
Tamworth, Staffs.
  1. If your 'speed' control is at anything other than 'zero' when you switch on, you will not get movement until the speed control has been zeroed for (at least) one second).
  2. If this is a v.3 Cobra, then it also has inertia.. This is set before you set speed-curves, and can be set to a l-o-n-g time-value. - Check inertia is set to lowest setting.
  3. Double-check you have the BEC / control lead connected to the correct channels of your receiver.

But you have probably done all this? :think:
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
OK, still bouncing along on the bottom - does the loco need to be connected, i.e the motor need to be in circuit for the ESC to start chucking out the necessary stuff?
Not that I am aware of. There are 2 pairs fly leads from the ESC's output terminals. One pair are connected to JohnS's bridge rectifier, going to the Sierra card's variable voltage inputs and there is no voltage showing there or at any point downstream. That in itself is a completed circuit even without the multimeter attached. As would the output going to the motor as the multimeter provides that completion on the circuit without the motor. I've also tested the outputs on the ESC itself. Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
  1. If your 'speed' control is at anything other than 'zero' when you switch on, you will not get movement until the speed control has been zeroed for (at least) one second).
  2. If this is a v.3 Cobra, then it also has inertia.. This is set before you set speed-curves, and can be set to a l-o-n-g time-value. - Check inertia is set to lowest setting.
  3. Double-check you have the BEC / control lead connected to the correct channels of your receiver.
But you have probably done all this? :think:
Yes I have to all the above and I have had a multimeter all over the installation - set to volts. The only thing I can think is there is something amiss in my method of doing the initial setup of the ESC, or a fault. But then I have read and re-read the manual, practiced and followed it to the letter and re-tried a few time to no avail. I will give Fosworks a call tomorrow and see if they can walk me through it. Max
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
24,973
479
North West Norfolk
Not that I am aware of. There are 2 pairs fly leads from the ESC's output terminals. One pair are connected to JohnS's bridge rectifier, going to the Sierra card's variable voltage inputs and there is no voltage showing there or at any point downstream. That in itself is a completed circuit even without the multimeter attached. As would the output going to the motor as the multimeter provides that completion on the circuit without the motor. I've also tested the outputs on the ESC itself. Max
I'd still be tempted to hook up the engine :mm::mm:
 
Greg Elmassian

Greg Elmassian

Registered
8 Mar 2014
2,787
153
San Diego
www.elmassian.com
remove other connections and add motor, simplify, isolate the problem.

I'm with Rhino.... I've done quite a few installs, and read every post of virtually every forum for 10 years... the statistics of success on a complex project where you hook everything up and it all works the first time is a very low success rate.

Greg
 
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
24,973
479
North West Norfolk
Why ? Max
The ESC might be programmed in such a way that it wants the motor in place before it starts delivering. I know it is intended to ultimately support stationary sound, but you never know the workings of the mind that programmed it.

For a start, I bet some ESC manufacturers haven't considered the concept of engine and tender ;);)
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
remove other connections and add motor, simplify, isolate the problem.
Greg
Done all that, again, still no action. My first test was to disconnect the the Sierra before firing it all up first time and checking all the voltage values. The ESC is not outputting any variable voltage. The Tx is most certainly bound to the Rx. Apart from the need for JohnS's gizmo to sort out the PWM going to the Sierra it's turned out to be a fairly straightforward installation, so long as you have the right information and bits.

If the ESC is receiving 18v and passing through 18v- allowing the Sierra to perform all its non-variable voltage functions, and all signs are that the Rx is bound to its Tx it seems to point, to an electrical illiterate like me, to some issue with the ESC, the ESC's set up and/or its ability to work with the TX it's plugged into. The rest of it is just making sure the current is flowing where it should do. Shouldn't it ? Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
The ESC might be programmed in such a way that it wants the motor in place before it starts delivering. I know it is intended to ultimately support stationary sound, but you never know the workings of the mind that programmed it.

For a start, I bet some ESC manufacturers haven't considered the concept of engine and tender ;);)
Granted, hence a word with Fosworks is in order. From what I can see on their website their background could be in G1 - plenty of tender locos there. :) Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
Rhinochugger

Rhinochugger

Retired Oik
27 Oct 2009
24,973
479
North West Norfolk
Granted, hence a word with Fosworks is in order. From what I can see on their website their background could be in G1 - plenty of tender locos there. :) Max
Yebbut, he doesn't make 'em I don't think. Just as Peter Spoerer didn't make his - I may be wrong :think::think::think:
 
Greg Elmassian

Greg Elmassian

Registered
8 Mar 2014
2,787
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San Diego
www.elmassian.com
so on the esc, there is power input, output to the motor, and the radio connection.

You've measured you have plenty of input power.... you have linked the radio, so hook up a motor and if it does not run, you have bad wiring, bad motor or bad esc...

easy to check the wires and motor

and the sierra might not draw enough to let the esc function...

simplify... power, radio, esc, motor.... what happens?

Greg
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
OK, still bouncing along on the bottom - does the loco need to be connected, i.e the motor need to be in circuit for the ESC to start chucking out the necessary stuff?
No idea, nothing in the manual to say it does - Need to have a chat with supplier to see if I have overlooked something or something is not clear in the manual. Max
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
so on the esc, there is power input, output to the motor, and the radio connection.

You've measured you have plenty of input power.... you have linked the radio, so hook up a motor and if it does not run, you have bad wiring, bad motor or bad esc...

easy to check the wires and motor

and the sierra might not draw enough to let the esc function...

simplify... power, radio, esc, motor.... what happens?

Greg
Thank Greg The ESC is only providing a voltage input to the Sierra to trigger certain sounds, its coming off the same terminals that supply the motor. The Sierra's main power is coming from the 18v battery via JohnS's card, that steps it down to 6v. As is its variable voltage input that come via the ESC on a separate path to take out he PWM. I'll plug the loco into my TE controller to make sure it is functioning. I'll have a chat with the supplier and see if I have overlooked something or the manual needs clarification. Max
 
Tony Walsham

Tony Walsham

Manufacturer of RCS Radio Control.
25 Oct 2009
2,112
10
Casino, NSW
Max.
Did you you program the ESC after binding had taken place?
That first time requires it must be calibrated as per the instructions.
Plus the required power curve selected.
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,529
146
Bucks/Oxon/Northants area
Max.
Did you you program the ESC after binding had taken place?
That first time requires it must be calibrated as per the instructions.
Plus the required power curve selected.
The instructions for the ESC were supplied on 2 single sided unstapled B&W xerox'ed sheets, rather than on the usual double sided coloured ones. I picked out the one with the power curve adjustment, only, printed on it and did that by mistake first and selected the "straight line" standard profile as per the steps noted. I realised my mistake when checking through the sheaf of paperwork for all the devices, in the tender in post #55, and found the other sheet with the calibration set up instructions. So I went back and did the correct first time calibration of the ESC and Tx as it should have been done in the first place, everything behaving as it should through each step. After doing that I got a constant slow blinking light on the ESC (so long as the TX has been switched on prior to switching on the loco). As I could get no voltage output at any point, I tried at least 3 more times to do the calibration process with no success. Each time I have checked for variable voltage outputs from the fly leads at the card and at the points where they input to JohnS's bridge rectifier for the Sierra card and the direct output to the motor. from the ESC. I have only once attached directly to the motor, again with no operation or voltages showing. I have not gone back to reset the power curve so I assume it is still set at what I inputted or the standard factory setting. I hope that makes sense Tony. Max

P.S. My only other experience of installing an ESC was a Mac5 that I do not remember needing calibration in conjunction with the Tx (a Spektrum Dx6) so i was not looking for that sheet initially. Excuses, excuses, I know but you can see how a novice could make this mistake under the circumstances.
 
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