The Shop > Electronics & IC Programing

KBIC controller probs

<< < (3/6) > >>

Gazz292:
this board dosent seem to have the overload led as mentioned, i've looked all ove the board for any surface mount leds, none to be seen, and deffo no thru hole mount ones, there's an empty solder pad set for a power on led too,

i think it is time to try the board on it's own, at least i'll know which board is giving me trouble,

Gazz292:
 :zap:
not really, it's the bottom board at fault,

she runs fine directo off the main board,


so what to do, the bottom board provides the tacho readout, but that part is still working, so i can re-wire it so it still gets power to run the tacho bit,
seems that board provides the brake, which only works when the emergancy stop button is pressed (i.e. remove main power, it dosent brake when i turn the speed control to off)

it also seems to provide some interlocking, i guess the thing to allow the motor to run only if the speed control is off,

i'm not sure if the main board can do that too, via the switch in the speed pot and the inhibit input,

i'll see if i can get those 2 transistors and see if that fixes the bottom board, but untill then, and if it dosent, i'll re-wire it to run only on the main board, with the direction switch in the circuit too,

i expect the bottom board also kept power off if the direction switch was changed whilst running, i always stop before changing direction on any power tool anyway, too much stress put on them, so it's only really the brake function i'd loose,

andyf:

--- Quote from: gazz on October 01, 2011, 11:53:33 AM ---.....i expect the bottom board also kept power off if the direction switch was changed whilst running, i always stop before changing direction on any power tool anyway, too much stress put on them, so it's only really the brake function i'd loose,

--- End quote ---


I think you're right there, Gazz - do a proper stop (big red button) before changing direction. Otherwise, according to the second warning on p13 of the manual http://www.kbelectronics.com/manuals/kbic_manual.pdf  it looks like damage might result when that switch disconnects completely in passing between the forward and reverse positions.

It's good that you have narrowed down the problem. If you can't fix the bottom board, you can probably get a new one from Amadeal. Unless you have already done so, it would be worth checking any safety interlock switches like the one on the chuck guard (if fitted). If one of those is open circuit when it shouldn't be, the lathe won't start.

Andy

Gazz292:
Deffo not the chuck guart interlock, that passes incoming mains thru it, so when it is opened it removes power, and thus trips out the no volt release switch, requiring the green button to be pressed to get power back after putting the guard back down,

the I2 terminal was fed from the secondary board, which i guess shut the main controller down when the direction change switch was operated, whilst it was braking etc,

the direction switch is a multi pole rotary one, havent traced their connections yet, but it has a feed into it from the speed pot's switch, which gets it's feed from the secondary board from a terminal marked 'TG'  and the switch in the pot is open when the knob is in the off position,

theres also wires to the reverse switch from the secondary board marked 'TA' 'V/2' and 'I/O'
there's also a feed into the direction switch from one of the speed pot's outer terminals, that's ran in paralell to the P3 terminal on the main board,

and L1 on the main board is fed from the secondary board, L2 is paralell with the secondary board, fuse,light and NVR switch.

Gazz292:

--- Quote from: John Swift on October 01, 2011, 10:13:08 AM ---78L05 is a 100mA 5v regulator in a TO92 case    http://www.alldatasheet.com/datasheet-pdf/pdf/6798/NEC/78L05.html

   John

ps        mcr 100-6 is a thyristor   http://www.alldatasheet.com/datasheet-pdf/pdf/4632/MOTOROLA/MCR100-6.html

--- End quote ---

so the 78l05 is prolly to power the led tacho display, if so it's working fine,

the mcr 100-6,
i guess it's suposed to block current flow one direction all the time, and when the gate is fed power, it opend and lets current flow the opposite direction?

seen the diagram from that data sheet, and i should get a short reading between the cathode and gate pins in both directions, but i should get a resistance flow thru anode to cathode, but not cathode to anode unless the gate has been triggered?
attatched the drawing of the pin layout from the data sheet,

i'll take it out of the circuit and test it, but it could be something else on this board thats gone.

Navigation

[0] Message Index

[#] Next page

[*] Previous page