Nonvolatile memory of the ancient KAREL RH controller

HI so i have an old as original sin GMF p-150 robot with an rh karel controller that ive been trying to get to work.Im probably going to retrofit it for fun bust im trying to see if i can get the old controller to work firdt. At first power up literally nothing happened it just wouldn't turn on. I bypassed the safety board and got the IO unit and the basic control unit as well as the drives to power up, the teach pendant displays the message teach pendant ready but the CRT remains blank, only the power on light turns on. Im aware that the firmware of the system is nonvolatile but im not sure nonvolatile means sit in a warehouse for 20 years and remain intact nonvolatile. Could it be the firmware degraded to nothing? Could the ram batteries being dead be the problem? Anyone with experience with these old units?

Sent from my SM-G892U using Tapatalk

That control uses the same Bubble memory for 'volatile' memory as the series 6,11 and 12. I would suspect power supplies, interlocks etc before the system eproms or BMU.

Quote:

---

Originally Posted by memoryman

That control uses the same Bubble memory for 'volatile' memory as the series 6,11 and 12. I would suspect power supplies, interlocks etc before the system eproms or BMU.

---

Yes it has the bubble memory board which is held by battery backup, i believe that is just for user programs profiles etc though. All the power supplies seem to be functioning i have over ridden all the interlocks cant find a blown fuse in the whole thing .....the crt has power but is blank..id expect it to at least give a no signal or a static screen...could this point to a blown crt? Also somthing ive noticed is many of the diodes in the basic control unit are corroded...but i dont know if thats just their shell or down to their core.

Sent from my SM-G892U using Tapatalk

Is the BMU a FANUC board? A real BMU needs no battery; regardless, parameters are also stored there.
What is the masterboard part #? Are there any lights on on the masterboard? Did you actually measure power supply voltages?

Yes i measured the voltages from the power supply and all checked out...i believe the bubble memory unit is fanuc ill have to double check...ive only been able to plug it in at my families facility i dont have three phase at my house but i have a rotary phase converter i could plug it into.....ill get back to you on the board number and the lights ....there are lights on the boards i just havent gone through all of them....thanks for your time...

Sent from my SM-G892U using Tapatalk

Fanuc did make a sram based BMU replacement (after we came out with ours in1991). Don't know if the battery on it was rechargeable. In my experience, a BMU error results in a 900-910 alarm displayed on the crt (likely a 904 alarm).
Possibly a rotary phase converter issue?

Its only ever been plugged into 3 phase mains no rpc. The crt has power, the filament heats up but it displays nothing no static no glow just blank....all boards power up the teach pendant says its ready but other than that its unresponsive.

Sent from my SM-G892U using Tapatalk

I had a CRT that glowed but no image/no static.

Then I saw a little burned hole in the flyback transformer.

Try unplugging the video signal to the CRT and see if you get snow. If you do then at least you know the tube still works.

So havent had a chance to repower it up yet but i have figured out a number of things from looking around in the controller and from reading the manual quite a bit..
The robot has an internal purge unit with a timer...this is stuck on...when i first powered up the robot i did not realize that this locked the unit out....the only respect i have gotten the robot powered up has been through bypassing the safety/ brake controller board...doing so distributes power to all respective systems, that being said on startup i now realize that there is a contact signal sent from the safety board to the power supply pcb..the manual is somewhat vague as to the purpose of this signal but my theory is that with power distributed in the absence of this signal..the system is in a kind of stand by mode. Last time i powered up the system i noticed a tuft of smoke coming from the control boards, i panicked when i saw this, thinking i had done something to fry it. On inspection of some of the boards i found a cooked diode. I remember the voltages being correct from the power supply pcb but ill need to double check. Any other reasons this could have blown? Im hoping it be just old age lol. The board is 24 volts with a .32 amp fuse, any thoughts on a replacement there are no package numbers.....also on a side note, at one point the robot was dropped onto the ground, not concrete but hardish texas soil... all the seem to be ok but im wondering if the encoders were likely shocked...just havent had a chance to hook a scope to them yet.

Sent from my SM-G892U using Tapatalk

Ok so i powered up the system....namely through bypassing the damn safety board again...the leds denote as follows main cpu leds read power on reset status, and cpu sub halt. Main buffer pcb has lights on that in the manual are listed as cpu status lights, a global non maskable data interupt light is on and the battery warning light is on..because the battery is dead. Axis cpu has 3 of 4 axis status lights lit and axis cpu overall status indicator lit.... now onto the crt controller board... the carrier detection led is lit denoting data transfer normal. On startup i hear the crt make the usual crt turn on noise...the crt starts with an ever so slight hint of glow then nothing. I unplug the signal cable and no change. I turn off the unit and the crt gives a bright green flash and squiggly lines for a brief second. So maybe bad crt? I double checked the power supply output pins....its hard to keep track of 32 individual pins but theyre set up in banks of 0 5 24 and 15 volts and each bank read normal. I replaced the dead diode also. Thoughts?

Sent from my SM-G892U using Tapatalk