On Monday 21st March when I reinstalled the boards on the underground allowing for the 2 input voltages the train just d in the centre part of the track for an unknown number of times. When I connected the traffic lights they seemed to work at random.
I went in this morning and trying to understand what was happening I realised the train was running in the opposite to the lights so I changed over the two wires to the track and then the train direction and the lights were correct but it was still oscillating in the centre, so I disconnected all of the sensors and then the train was running the full length of the track much as it should. I tried fitting one sensor at a time in various positions all of which caused problems.
So at the moment I have left it running without any sensors connected, and it runs acceptably.
Reintegration of the System with O/C Protection and WiFi
Re: Reintegration of the System with O/C Protection and WiFi
Geoff,
I was in WMT this afternoon and had a look at the Underground amongst other things.
I can't shed any real light on the sensors problem but I can say that the train is not supposed to oscillate continuosly between the two ends. The electronics and software was thoroughly tested before I brought it back; both with the operational software and with the hardware test program. I did not identify any faults.
As a start however I would suggest that you check that the Guard Rail button is working properly. The input is pulled up to 3.3 V so if you monitor between Pins 11 and 16 you should see this voltage. Trigger the button and the voltage should fall to 0 V.
Similarly if you monitor the sensor Inputs on Pins 7, 8, 9 and 10 wrt Pin 16, you should see 0V until the train passes over the sensor when you should see 12 V.
At the moment I think that the train is only being stopped by the timeouts in the code and / or the track breaks.
The WiFi is working well.
I was in WMT this afternoon and had a look at the Underground amongst other things.
I can't shed any real light on the sensors problem but I can say that the train is not supposed to oscillate continuosly between the two ends. The electronics and software was thoroughly tested before I brought it back; both with the operational software and with the hardware test program. I did not identify any faults.
As a start however I would suggest that you check that the Guard Rail button is working properly. The input is pulled up to 3.3 V so if you monitor between Pins 11 and 16 you should see this voltage. Trigger the button and the voltage should fall to 0 V.
Similarly if you monitor the sensor Inputs on Pins 7, 8, 9 and 10 wrt Pin 16, you should see 0V until the train passes over the sensor when you should see 12 V.
At the moment I think that the train is only being stopped by the timeouts in the code and / or the track breaks.
The WiFi is working well.
Re: Reintegration of the System with O/C Protection and WiFi
This morning when I went in I found that both the underground and Milkshake lines were turned off at the back. turning them both on the Milkshake train worked fine. The Underground did not move the traffic lights were working on taking the loco off and testing it all appeared to work fine. On replacing back on the track I could tell that it was getting some power but not enough to move it. I checked the track voltage and it was about 5V.
On checking the voltage output I found that the output resistor had been moved along the slider which would account for the low voltage. On resetting the resistor the underground was running as expected.
Later in the morning after quite a bit of use I saw it was stopped in the middle nothing happening! On checking the output I saw the overload trip had tripped! On checking the loco, for a few seconds it did not run and the ran as normal, so all I can assume is that there must be an intermittent short in the loco. I have taken it home to give it a full rewire before I put it back on the track.
I have put the back up loco on the track for the time being.
You are quite correct in saying that without the sensors connected it is running on the timeouts and the diodes at the ends.
The sensors seem to be picked up in the reverse order since the output polarity to the track has been reversed from the unit, but I have not been able to confirm this?
On checking the voltage output I found that the output resistor had been moved along the slider which would account for the low voltage. On resetting the resistor the underground was running as expected.
Later in the morning after quite a bit of use I saw it was stopped in the middle nothing happening! On checking the output I saw the overload trip had tripped! On checking the loco, for a few seconds it did not run and the ran as normal, so all I can assume is that there must be an intermittent short in the loco. I have taken it home to give it a full rewire before I put it back on the track.
I have put the back up loco on the track for the time being.
You are quite correct in saying that without the sensors connected it is running on the timeouts and the diodes at the ends.
The sensors seem to be picked up in the reverse order since the output polarity to the track has been reversed from the unit, but I have not been able to confirm this?
Re: Reintegration of the System with O/C Protection and WiFi
Geoff,
Are you saying that the voltage from the electronics has been reversed? If so I'll fix it if someone can take it out.
I must say though that I'm a bit surprised. Surely the Train wouldn't run in the right direction when it was placed on the track at the store end?
Are you saying that the voltage from the electronics has been reversed? If so I'll fix it if someone can take it out.
I must say though that I'm a bit surprised. Surely the Train wouldn't run in the right direction when it was placed on the track at the store end?
Terry
Re: Reintegration of the System with O/C Protection and WiFi
Yes that is what I am saying and presumably why it was causing the initial problems with it running erratically in the centre of the track.
I think I have found out where the intermittent short was coming from. I have rewired the the electrics but I did not find any problems. On examining the drive units I found the flanges of the wheels was very close to the magnets of the motors and over time the magnets had picked up swarf from somewhere and occasionally causing it to short. I am proposing to increase the clearance and paint some resin on the magnets to stop that happening.
Geoff
I think I have found out where the intermittent short was coming from. I have rewired the the electrics but I did not find any problems. On examining the drive units I found the flanges of the wheels was very close to the magnets of the motors and over time the magnets had picked up swarf from somewhere and occasionally causing it to short. I am proposing to increase the clearance and paint some resin on the magnets to stop that happening.
Geoff
Re: Reintegration of the System with O/C Protection and WiFi
Geoff,
When I re-assembled the system after getting the Over-current Protection Circuit working, I found that during testing the track voltage was increasing negatively initially, instead of positively as I originally wrote in the test instructions, so I reversed the wiring to the output pins. With hindsight, it is possible that the wiring was always reversed, so I have introduced a new problem. I don't quite see how the original system passed its tests, but maybe this was found during the original integration and the wires reversed back then to overcome the problem. Can you reverse the track wires at the Terminal Block on the unit to overcome this?
Terry
Re: Reintegration of the System with O/C Protection and WiFi
Hi Terry,
Would it be possible to reverse the output polarity. At the moment it is only running on the time out and the end diode end sections, rather abrupt stops.
I Have been trying to set the track sensors so that it stops on them but at the moment I can't make any sense with them in any positions even though as far as I can see it should be possible. I am hoping that with the reversed polarity it will all make sense.
Would it be possible to reverse the output polarity. At the moment it is only running on the time out and the end diode end sections, rather abrupt stops.
I Have been trying to set the track sensors so that it stops on them but at the moment I can't make any sense with them in any positions even though as far as I can see it should be possible. I am hoping that with the reversed polarity it will all make sense.
Re: Reintegration of the System with O/C Protection and WiFi
Geoff,
I don't see how reversing the motor wiring would solve that problem. If the train was running in reverse it wouldn't move out from the station at the store end. To me the problem seems to relate to the sensors.
You should be able to reverse the polarity at the Terminal Block as I mentioned back in April. Swap the wires at TB1a Pins C and D, see below.
I've never understood why these wires got reversed in the first place, since everything worked originally. Unfortunately, I'm still avoiding spending too much time inside public buildings, otherwise I'd come in and have a look myself.
I can only suggest monitoring on the Sensor outputs, see below.
- Underground_Railway_Circuit_(with_Over-current_Protection)_(V0.15).png (314.49 KiB) Viewed 295 times
Terry