MC2100 treadmill motor control circuit

MaxHeadRoom

Joined Jul 18, 2013
23,790
If the light is a steady flash, it means that the processor is receiving a command from the console.
Check the 105VDC from the bridge -ve to Q1 or whatever the designation of the SCR on the HS is.
Test input and output pin before and after a command is issued.
 

Zero3000

Joined Aug 19, 2021
4
If the light is a steady flash, it means that the processor is receiving a command from the console.
Check the 105VDC from the bridge -ve to Q1 or whatever the designation of the SCR on the HS is.
Test input and output pin before and after a command is issued.
Thank you very much for the useful information. I’ve tested the input (anode), output (cathode) and the gate of the SCR. The output of the bridge rectifier is connected to the anode of the SCR (Q3 S8025L) +V(floating). The output (cathode) of the SCR is the HV bus (TP3). I have measured the voltage vs the TP4 (0V float), with speed selected to 0 Km/h (Stop), and with speed selected to 2 km/h.
With speed 0 Km/h V(A) = 215 V
With speed 2 Km/h V(A) = 212 V
With speed 0 Km/h V(K) = 15.8 V
With speed 2 Km/h V(K) = 317 V
With speed 0 Km/h V(G) = 15.8 V
With speed 2Km/h V(G) = 317 V
 
JBG - I have used your excellent schematic to fix an MC2100ELS-18W board, thanks again for your hard work. In the process of fixing (details in another post) I came across some anomalies in your schematic. Attached is an edited schematic - please verify my changes and update and re-publish your master copy if needs be. There is always the possibility that my board is at a different rev level than yours.
Hi,
Sorry for the late reply but I have only just been notified there was some interest in the posting.
I make no excuse for the drawing mistakes, should have noticed the short circuit across the transformer and the fly-wheel diode not across the motor! Getting old I suspect. The opto/scr driver was taken from a stock library, should have modified it as you did.
I have re-draw the schematics and re-issued as a new posting.
Just curious what software did you use to enable you to modify the original .pdf file?
Glad my input to the forum helped, I have another one to add later.
Best regards.
 
Due to some drawing errors, which Mach4 kindly pointed out, I have made the corrections and, for completeness I have re-issued the complete set of information (attached). I did notice there are some small differences between the one I reverse engineered and the replacement I had to purchase.
Trust somebody finds this of interest.
Keep safe.
 

Attachments

Hi,
I would like to contribute to this excellent site my reverse engineered information for the MC2100ELS-18W controller card. I was asked to "repair" a treadmill which had this card. The first problem was the shorted control "transistor" IRG4PC. This was locally available but on replacing there was a flash-over along the glue for the paper label which took out the micro-processor! A new card was purchased, different component lay-out but the same circuit except for an additional capacitor in series with the original connected between the 2 different system zero volts. No problems encountered with the new card although being an old school systems design engineer I do not like the control system. It appears there is no feedback when there is somebody using the treadmill, the speed varies too much for me. Yes the belt speed sensor appears to be working.
Anyway I trust somebody has a use for the information.
Any faults please advise and I will correct. There are some Zero ohm surface mount resistors which seem a little strange for me.
Update 06-09-2021
Please see #245 for corrected drawings.
 
Hi,

You are correct with the value of R60 it should be 10K. I also unsoldered R53 to check the actual value and it is 1Meg. The colour coding is not what I remember from many years ago, Br, Bl, Gr used to be 1Meg. I also rechecked the component list and corrected R43 and R47, (copy and paste problems).
If the system is shutting down due to over-current then something is wrong. Is anything getting hot to touch?
I mentioned there could be 2 ways for protection from over-current:-
1 Pin 6 of U10, if you check the data sheet, is current protection, Cs.
2 Actual current, measured by R63, is sent to the processor (pin 4) and also could control the PWM to the drive controller (sheet 7 pin 8), U10.
If you really want to change the feedback current, this is on your own head, then a potentiometer across R63, with the wiper connected to R60, would allow you the vary the feedback.
Good luck.

I have attached a new version of the components list and corrected drawing sheet 2.
Update 06-09-2021
Please see #245 for corrected drawings.
 

Zero3000

Joined Aug 19, 2021
4
So it appears the SCR ramps up the motor power, the other suspects would be The mosfet or its gate driver IC, MC4227
Thanks for your suggestion.

I’ve tested the IGBT previously and seems working.

Now I’ve measured with the multimeter the electrical tension at the IGBT driver: U10 (IRS2127P), in the following order.

1st: console switched OFF

2nd: setting the speed to 0

3rd: setting the speed at 2 Km/h.

I noticed that tension at the 2nd Pin (Pulse Modulation IN) is always 0 Volt. I’ve measured it with the multimeter not with an Oscilloscope.

Console OFF
[ V ]
Console ON - STOP (0 km/h) [ V ]Console ON - START (2 km/h)
[ V ]
  • Vcc
11.315.217.2
  • PMin
000
  • Not Fault
25.65.6
  • COM
000
  • Vs
000
  • Cs
000
  • Hout
000
  • Vb
10.63.216.3


So it seems that the microprocessor (CY8C24223A) isn’t giving signal to the IGBT driver (U10, IRS2127P). Actually, the microprocessor seems working: when setting the speed to 2 km/h, the board’s LED is flashing. So I think that I have to understand what is preventing the microprocessor from giving the PWM to the IGBT driver U10 (IRS2127P). Any suggestion is welcome.
 

Zero3000

Joined Aug 19, 2021
4
I have founded the fault. It was the IGBT gate driver's IRS2127. It had output zero, when the input was different from zero. After changing it the motor started to run beautifully.
I would like to thank you everyone who collaborates to this forum and especially JohnnyBeGood for the excellent schematic and MaxHeadRoom for his prompt replies.
 
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