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FP3 CNC "No Signal" on CRT.

repot

Plastic
Joined
Jun 28, 2019
I visited a Deckel FP3 CNC with flip-head this morning. Unfortunately the control does not work anymore. It is a dialogue 4. The CRT shows only the message “no signal”. Maybe someone is familiar with the message and how to solve it? I’m considering to buy the machine, but I know that repairs can be very costly. Thankx for your advice and support!
 
My TV at home and my PC monitor gives me the "no signal" when the PC is off, or the wrong source on the TV is selected. Maybe a video board? Connection to the screen?
 
I have no familiarity with that equipment but if the CRT is displaying "no signal" I would not suspect the video card or cable. If they aren't working the screen should be blank.

I would more likely suspect it means no signal from a position sensor or something along those thoughts.
 
I have no familiarity with that equipment but if the CRT is displaying "no signal" I would not suspect the video card or cable. If they aren't working the screen should be blank.

.
Dunno about the old Grundig monitors but LCD monitors will display “no signal” if there either is no feed from video card to monitor or if horizontal frequency input is too low Hz
 
Some general info:
Don't have the answer as to what the source of the error is.
But i will tell you that think other problems might provoke such a message....Being this is a new to you machine think investigation would be in order....

Power supply board problems can cause lots of faults....need to be sure that the NSV board (furthest to the right looking from the rear) has all the red LED's lit....
If not that is a starting point. NSV boars is quite repairable...Local member here does upgrades to latest factory specs on these......

Also the NCR (video) board can be an issue.....On my FP4NC it killed 3 video boards(rebuilt) in 5 years,before i bit the bullet and bought an LCD conversion.
That was some of the best money i ever spent on that machine......Been dead reliable since the replacement.
Best part is that the internal temp of the control has been lowered about 50*F with the change.....Better for the life of all those aging electronic components housed within.....

Further there are three battery packs used on that machine....If the 7.8v battery in the lower portion of the control is low or dead, the control likely will not start up...Possible to make things start if the control power is left on
for an extended period , say an hour or more...Some recharging of the battery is possible unless it is truly dead.
Further there is a battery on the memory board (NSP) that retains programs and software settings (like inch or meter) Possible to start the machine if this battery is dead, but can't retain any
saved info when powered down...
Finally there is a third battery on the NSV80 or NSV90 board (depends on which version "PC" the machine has, most likely this one is an NSV90)

Some info here:
https://www.practicalmachinist.com/...6/index3.html?highlight=Dialog+Battery+Change
See post #49

https://www.practicalmachinist.com/...not-start-up-329941/?highlight=SAFT+Batteries
Cheers Ross
 
All battery packs have already been replaced. But it didn't solve the problem. First I have to get the machine home. Then the debugging starts.
 
Dunno about the old Grundig monitors but LCD monitors will display “no signal” if there either is no feed from video card to monitor or if horizontal frequency input is too low Hz

Yeah, I was basing my response on it being described as a CRT for which as far as I know there were never any with even minimal on-board signal generation. If it is indeed an LCD or other flat screen display then I think all of them have on board circuitry to generate some kind of "No Signal" display in the absence of an external signal.
 
I got the machine home this afternoon. Connected it back to the power. I made some pictures of the control status. Maybe someone can help me out with what is wrong. I also noted that none of the fans is working. Or are they only activated when the temperature is too high?

Some pictures:
IMG-4935.jpg

IMG-4937.jpg

IMG-4938.jpg
 
Looks like you have an LCD conversion for your display.
Most likely nothing there is the issue.....

Muffin fan in the operators console should be running all the time when the main power is on.

Fans in the main cabinet should be running when the control is powered and there is no faults.
Main cabinet fans will not run if the door they are mounted to is open. There is an interlock at the top of that door opening and you can manually switch it to check the fans with the door
open.
Main fans are a bit fragile. Seen them fail when the blower rotors get full of dirt that makes them stop rotating...then the motors fail....

Cheers Ross
 
There's a connector for a coax cable on the bottom of the console, that can be connected to a remote monitor or TV set with a compatible connector. The signal comes from the white wire connected to the center of the 4th card from the right in the photo of the open console. Perhaps connecting a monitor to that output would show something different than the machine monitor and help diagnosis?
 
Continued the search today. I found out that the relay on the NSV90 does not close. Most likely caused by the NPP90, which signals that there is no communication with the main computer. So I continued my search in the console. I found in a German forum a similar error which was caused by low battery value on the memory board. The previous owner told me that all the batteries have been replaced. But when I inspected the the battery on the NSP board it looks like the minus side is not connected! I can not see any visible tracks on the print which connect to the minus side. I tool some pictures. Maybe somebody who replaced the batteries already can comment.

IMG_0056.jpg

IMG_0055.jpg

Detail_0001.jpg
 
There are 4 pins on the battery. The lower two in photo #2 are the "plus" connection
Think gustafson is correct. The connection in photo #2 next to the red arrow has an internal connection as does the one on the outside edge.

If you want to test to see if the battery is making a valid connection , test for voltage between the terminal where a trace is visible. (upper left in photo #2)
And the trace that is just above the battery terminal that appears to have no trace (red arrow)
Should see the battery voltage (3.8v) there if the battery and the connections are good.
To be sure, i place my meter probes on the actual solder blob at the end of the trace away from the battery post so i am sure i am reading the actual connection and not the battery post by mistake.
Have seen these battery replacements not work due to crappy instillation technique.

If you find that you don't have a good connection, you can place a wire jumper between the plus battery post and the trace i mentioned for testing.(red arrow)
Some owners remove the battery and use soldered on leads and place the battery in the bottom of the cabinet. Allows use of more easily available batteries.

Cheers Ross
 
So far nothing helps. Re-soldered the batteries. Connected an external tv to the coax, but also nothing there. Checked all the voltages again. The cnc remains dead in the console. There is no sign of life.... It looks that the CPU is not coming to life after power on. So I have to consider my options.....

One of the options is an other cnc controller. I like to keep the servo's and the bosch drive. Maybe it is also an option to keep the "PC" where all the I/O is connected to. Is there any documentation on the communication between the "PC" and the "Cnc"? It looks like a serial protocol? I know that in today's controllers the closed loop is more on driver level then on controller level. This makes the reuse of the bosch drive more complex. Also the heidenhain scales are most likely sine/cos rather then TTL.

Other options are to start looking for somebody who can help me with the repair or a donor control...
 
Dialog controls are generally repairable in most cases.
Boards have discrete components and the orange book has the diagrams of most of the cards.

As to other options...FPS in Germany does control retrofits using the current Heidenhain 320 Control i believe and their change employs the
original servo drive (Bosch) and Servos (Siemens) as well as the Heidenhain linear scales.

That original; equipment is pretty good. First line stuff when the machine was built. Servo motors are reputed to be "bullet proof"
And the scales (HH) are first quality.
All that stuff is well matched, scales fit the slides , servo motors fit directly and have features on the "Z" servo that would be pretty difficult to substitute something else.......(hand wheel drive gear box etc)

You are in the right part of the world and there should be some competent help local to you.

Did you make the voltage test that i suggested above for the battery?
Is the battery charged?

Start with the simple stuff:
Power off.
Remove each board in both the PC and the control (one at a time)
Lay the board down on some wood and press down firmly on every IC that has a plug in type socket..(re-seat)...Thermal cycling often will loosen the connections.
Test every fuse in the machine (control and PC) with an ohm meter to verify continuity.
 
I checked the batteries. Not only the soldering points but also down the trace. Voltage and connections are ok. All batteries are charged.

I took all the boards and pressed the IC's down in the their socket. I tested all the fuses and also they are ok.

Yesterday I took the NSV from the PC and from the Control and measured all the voltages. The plus/minus 24 V seems a bit high : 28.4 V. This is difficult to lower because on all the transformers the +5% is already in use. But I assume that the 24 V is not directly in use by the boards. Only the -15 V is a little bit low: -14.7 V. But seems to be within the specification range of the uA7915.

The NZP's seem to work. They indicate no error and the led's respond to axis move.

I still suspect that is has something to do with the main CPU in the Control. There is no output to the CRT, not even a fault code, and no communication with the PC. The Control does not respond to any input.

The hart of the control consists of several boards. The problem is that they are well hidden inside the console and very difficult to reach for measuring. They all need eachother and are therefor difficult to test in a stand-alone configuration. Now, could there be a common problem that alle the boards suffer from because there is no response at all, or is it most likely that only one of the boards has a problem?
 
I would be very suspicious of the NPP90 board in the PC .
The communications are bi directional so if either side is not working , the system will not boot up.
Need to find another member here that is somewhat close and has the same control to perhaps swap the boards to see where the problem lies....

Cheers Ross
 
I have a working Dialog4 with a not so much working machine down in Switzerland. I could swap-test and perhaps repair your cards, if you bring them to me (like if you go south for holydays).
 
Thanks for the offer! Very tempting. At this moment I'm investigating the option to replace only the control part. I agree that the servo's, scales, etc are very well dimensioned.
 








 
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