🚀 go-pugleaf

I have started a new thread as earlier I had crossposted to uk.telecom
(regarding the 1471 recorder) and robotics/electronics is not directly
relevant to them.

>In the process of testing the circuit I must have blown something on the
>i/o card as the voltage has dropped from 4.3V to 3.2V on one of the pins
>( I was warned about this, but at least I wasn't using my 586 with on
>board i/o). I checked some resistors on the card and replaced one 22ohm
>that had risen to 34 ohms but still only get 3.2V. Any ideas ?

>>The output voltages on com ports ought to be in the range +5 to +15 or
>>the range -5 to -15.  Three point anything seems a bit pathetic !

Although my original thread mentioned com port interfacing which can
give +15V, after receiving various emails regarding parallel port
interfacing being much easier, I opted for parallel port controls which
gives 5V. I neglected to mention that I had built the driver circuit for
the parallel port.

>I am now using a spare i/o card which gives slightly more than 5V on
>pins 2 to 9. However the 'logic' is the opposite way round to the last
>card i.e. PC boots with pins set high, releasing 5V, I then set all pins
>low by sending 1's not 0's (out &h378,127) in my autoexec. I then need
>to send 0's to the pins to set them high. I have had to edit my software
>which I wrote for the first card to operate my second card. Is it
>correct for different cards to have different logics, or am I doing
>something wrong.

>>The two uarts may have different behaviors when reset.

See my subsequent post ( I had crossed a wire in the cable I was using).
All is fine now apart from the low voltage from the original i/o card.

>I am still looking for interfacing details for 3 phase motors. My friend
>bought a cheap  'robotic  (CNC) manipulator' at an auction which has
>several  stepper motors used to manipulate the  'tool holder' position.

>>OK, but 3-ph and stepper motors aren't the same thing !  What exactly do
>>you want to control ?


>We have no details on how it operates and numerous wires have been
>severed (but they are colour coded).  I should be able to write software
>to manipulate the tool holder but I first need to build/buy the
>interfacing circuits. I will find out what power ratings the motors are
>and post them here when I have them. Can the cassette recorder driver
>just be uprated for the higher power required by the 3 phase motor (with
>a solid state relay replacing the transistor).

>>Depends what you understand by 3-ph.  Are we talking mains powered star
>>or delta wired steaming great 240/440 Volt thing or are we talking
>>stepper motor ?

>>A 3-ph motor will require a 3 pole relay/contactor.  A stepper motor
>>will need a stepper controler or some software that you write to drive
>>power transistors to control each pole of the motor.


Several people have asked me to clarify if I mean 3 phase motors or
stepper motors. To be honest I did not really know when I first posted
as I had not seen the Robot for about 18 months (and I do not know the
difference between single phase / 3 phase etc).

On Saturday my friend ( who owns the robot) and I tried to get it
running. The 'Robot' is a Pentel PR 1000 manufactured in the Far East in
1987, a 4 axes control unit (approx 2' X 2' X 3.5') interfaces a 2 axes
Pentel manipulator driven by 2 stepper motors with proxomity switches
etc. The control unit has a teach pendant and several 36 way data cables
which passes instructions to the motors.

 Is anyone familiar with Pentel Robots ? Looking at the numerous circuit
boards, 100's of LED's, relays and transformers we guess the machine
must have cost somewhere in the region of �20000 when new. The control
unit even had two top quality magnetic screwdrivers and 2 spare fuses in
an unopened plastic wallet.

We reconnected all the damaged cables and then tried to decide what
'juice' the beast required. My friend who is an 'engineer' checked the
power input terminal and it was marked up 250V so HE decided it was
standard 240V mains supply and we wired up a plug. After blowing 3 13A
fuses and receiving several large 'cracks' we decided all was not right.
A CNC engineer who was present took a look and decided the control unit
ran from 110V not 240V. We wired it up to run on 110V, with a 5A fuse
and although we got a 'crack' the fuse did not blow and the two internal
fans which keeps the control unit clean and cool began to run. 

As the Pentel was purchased 'as seen' , without manuals, wiring diagrams
etc I hadn't really thought that we would get the control unit running
and that's  why I was looking to write some code to control the two
stepper motors via a PC and ditch the control unit.

We checked the main transformer in the control unit after the 'cracks'
to see if we had 'buggered it'. The output voltages marked on the
transformer are 80V 4A, 10V and 10V  and the meter shows the transformer
to be fine. The 80V 4A appears to be for the motors and the 10V for data
transmission. We had to 'hot-wire' the control panel on the control unit
which required a key to power it up and another key to set the
programming mode to home, auto, run etc. We got no sign of life from any
of the LED's so we began to strip the control unit down (feeling really
stupid that we had been earlier feeding it 240V ). Some circuit boards
had up to 4 2A fuses soldered into the board and others had glass fuses
in holders. 

We pulled out a power supply card (using one of the supplied long
handled magnetic screwdrivers which must be worth as much as my friend
paid for the complete Robot). The card had an 18" long heat sink
attached to about 8 Triacs and 4 Diodes along one edge. We had blown at
least one Triac and one Diode which stopped power reaching the control
panel but the fans were powered by another circuit which is still
intact. We are in the process of replacing the blown components and will
see how things go.

The 3 or 4 data cables pass through a 'junction box' and then to the
stepper motors. The junction box doesn't seem to have any purpose but I
guess it must do something. There is a cable running from the control
box to 3 transformers about 4" X 4" X 4" each with no markings. The
transformers are fixed to a steel plate with no casing and give the
impression that they have been added as an after thought. We guess they
step-up or down the power to the motors or the data supply ( I think
that covers all possibilities).

We eventually finished at 11.30 pm Saturday. If we fail to repair the
control unit I will look at PC control again. For now I suggest no more
postings are made to demon.tech.pc as it is now some what off topic.

Sorry for the length of this post

BFN

Paul
>Cheers, J/.
>John Beardmore
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