(this chapter is so far a fragment)
So, let’s start to go a little bit into the technical side of the machines.
First off, one must emphasize that the machines are very reliable and robust, but they are operated under very different use and treatment conditions, which very much drive their reliability.
To maintain a Dialog 1 to 4 or Contour 1 to 3 machine can be quite cheap, or way more expensive, depending on which approach is chosen. A machine that is operated in a professional environment, and must be used every day, will have significantly higher operating cost then a machine in a hobby shop environment, where it may not matter if the machine is out of service for a while. The difference is that the professional will not have time to exercise all cost saving possibilities, simply because the machine must be up and running as fast as possible. He will simply order the needed parts from the established vendors, and will be done with it. Luckily this approach is still possible and no obsolescence problems will affect owners for some time to come. The hobbyist on other hand is surely willing to trade some “up”-time for some “down”-time, if it will save him some money. And indeed serious money can be saved this way.
A professionally daily used FP NC with good maintenance and good treatment should still have a "mean time between failure" (MTBF) of years and should have a "mean time to repair" (MTTR) of a few days (in central Europe).
In any case, the assumption is that you want to maintain or fix a Deckel NC machine, and you want to do it yourself, and it has a Dialog 1 to 4 or Dialog 1 to 3 control.
Prerequisite for electrical work: You have studied the orange folder with all the electrical information and are familiar with it!
If you do not even know yet where your circuit board cards are located individually, do not bother to start troubleshooting.
Read first, then prod!
1. Maintenance
1.1 Lubrication and hydraulics
Oil specs: use recommendations from maintenance part of manual, but note that the Mobile way oil has been reformulated and the correct stuff is now sold under a different name (Vacuoline),
1.2 Adjustments
1.2.1 Mechanical adjustments
Spindle maintenance:
When running the spindles at higher speed, they will heat up slightly. On the horizontal spindle this will lead to the quill beginning to stick! The quill can eventually no longer be moved! After the spindle is stopped it will take only a few seconds until the quill can again be moved. This appears to be normal and is no reason for disassembly.
As maintenance, the spindles on the needle bearing machines should be disassembled, cleaned, re-greased, and re-assembled with re-adjustment.
Axis adjustment:
1.2.2 Electrical adjustments
1.2.2.1 Offset and Drift
Each axis must be adjusted for drift and offset. This means that each axis must be able to hold its position without feedback (should not wander off) and when moving must not lag behind the programmed values. If the offset is not correctly adjusted the machine will be inaccurate and it may also shut off because the difference between the programmed value and the actual value becomes to large. To tune offset and drift the Bosch card must be adjusted. This is only possible if the correct resistors are installed. The resistor values are different for each machine. Within each machine the X and Y axis are identical, but the Z axis is different. Accessories also have different values, sometimes even depending on the serial number. A badly adjusted Bosch card will lead to a spike in current, which will lead to shut off. This will first occur in a rapid move, because that is where the most current is pulled.
A detailed description for setting drift and offset is to follow.
2. Repair (Electrical)
Note that the Dialog 4 card slot layout shown in the orange, that comes with the machine, may be false. The correct card population is:
VG1 to 4 NZP59
VG5 NRP53
VG6 vacant
VG7 NPP54
VG8 NEP52 (or 52A for DNC)
VG9 NPP55
VG10 NSP55
VG11 NSI56
VG12 NCR53
VG13 NSV56
Orange Book: http://www.dialog5.com/circuitboardprints.htm
2.1. a. Initial checks and reset
For Dialog 4 or Contour 3, reset control by removing the 4 way jumper connecting slot cards 8 to 11 while under power. Re-attach with power off. Re-initialize in Mode 16 with power on.
( It appears that some people do not understand what to do here. So I created a special write up for this here: http://www.dialog5.com/resettingdialog4.htm )
If nothing at all shows on the screen, check that brightness knob on bottom is adjusted correctly. After that check if monitor has power (LEDs on NSV board, they must all be lit).
Dark monitor has also been fixed by reset on occasion.
If you suspect a bad monitor, hook up a flat screen TV-set to the sub-miniature TV hook-up on top of the control (most flat screens will do an auto set-up to go to PAL mode).
b. Error codes
c. External power supply
Are all 3 phases of the power supply ON? (don
d. Batteries
The machine has a total of 3 batteries. One is in the PC (programmable controller) on the NSV board, one is on the bottom of the control housing under the operator panel, one is in the control in the console on NSP55 (Dialog 4, pictured here: http://www.dialog5.com/nsp55.htm ). These batteries get very old, but they are usually even older. If you own a Deckel NC and are to cheap to buy a new set of batteries every 10 to 20 years, you should sell the machine and get a manual machine. Note that a bad battery may create the "monday morning" effect in professionally used Deckels. This means that a machine will not start up on a monday morning (particularily when cold), because over the weekend the battery charge went down and is now to low. Having the machine sit with main power on will recharge the batteries enough for normal start-up, probably till the next weekend. When soldering in new batteries, make sure that you are putting them with the correct erminal orientation. For that purpose also check how the old batteries were installed.
Batteries almost always have a manufacturing date on them. The blue battery shown below was most likely made in the 15th week of 1998.
The original manufacturer "Saft" states a shelf life of 10 years. Unfortunately they keep changing their designation of the battery type. Beware of putting in very cheap batteries. Leaking batteries have been known to completely kill a board.

"Saft" memoguard cross reference table: http://www.dialog5.com/PDFs/Saft ListeBW.pdf This list is only for the batteries soldered onto the boards.
Note on Battery replacement: I now know first hand of 3 separate instances where different official Deckel service persons have repaired or serviced an FP NC without considering it necessary to replace 10 to 20 year old batteries, with the effect that these batteries failed shortly thereafter causing great confusion and mild panic with the owners. I also know instances where others HAVE done it. Lesson: the proximity of a knowledgeable person will not automatically rub off on a machines condition. Check! Soldering in a standard rechargeable battery onto a printed circuit board may produce a mechanical strain during transportation a cause shorts.
e. Tachometers
Each axis motor has a tachometer. The tachometer tells the machine how fast the axis is moving. If the tachometer is dirty or the brushes are worn, many funny symptoms can occur, for example axis jerking, sometimes only noted by sound, because it can sound like a major mechanical defect. The tachometer cables must also be hooked up correctly. Reversing them will tell the machine it is moving the wrong way, which also creates "emergency stop".
f. Scales
A "V" (Verschmutzung) displayed on the screen behind the axis display indicates that the axis scale needs to be cleaned.
g. Symptoms
If the axis are jerking upon turning the machine on, the NRP53 board may have a problem. Put in a different NRP53 board to see if the symptom is changing, or test your board in a different machine. A bad NRP53 may make all axis jerk, but it may be more pronounced on a single axis. Watch carefully if all axis jerk. If all axis jerk, it probably is not a problem of the scales or tachometers.
If the display freezes up when you move through mode 4, unplug your electronic handwheel. If problem goes away, there is a problem in the handwheel, for example a bad button.
2.2 Bosch side
Each axis has 2 Bosch cards.
The machine can be turned on without Bosch cards, or with just one axis removed. This simplifies trouble shooting. If an axis will go into an emergency stop upon a programmed G00 fast forward move, then this indicates that the axis optimization is out of spec, which causes the current to spike. Do an offset/drift adjustment. If this is not possible you may have to check the values of the tuning resistors/capacitors. On the newer Bosch cards there is a small piggy back optimization card. Optimization values are the same for the x and y axis. Z is different (heavy). It is yet again different for the accessories.
When turning on a machine with the z-axis cards removed, the Z-axis must be supported by a block of wood, as otherwise the axis may come racing down.
Bosch cards are newly produced by different sources, but are quite expensive. On the other hand they do not go bad very often and can often be fixed if bad.
If the machine has a problem and is experiencing emergency shut-off for unknown reasons, it is possible to unplug the axis cards in order to check if the fault can be attributed to them. This way it is also possible to check each axis individually for functionality. Do not forget to support the Z axis with a block of wood.
2.3 Control
There are a bunch of diodes on the cards in the control console.
All diodes on the NSV (slot 13) must be on. These indicate the different power availabilities. NSV cards are fixable without being a Deckel specialist. First thing to go is usually a transistor (power spikes, shorts). Do not remove monitor with power on, touching the NSV will kill that transistor.
Blinking diodes indicate a problem.
Diodes on NZP cards must blink as the axis are moved.
NZP cards are interchangeable between the axis, but must be set up according to their use (dip switches).
I will insert a picture here what the normal lighting mode should be.
2.4 PC
More diodes. Picture to come.
Note that 2 different kinds of PC were used, the PC1 (80 series) and the PC2 (90 series). They are not interchangeable.
Dip switches on the NPP80 or NPP90 boards determine the machine configuration, options, settings.
2.5 Software and EPROMS
There were several different SW levels. The last one was 3.07 on the D4. This one introduced DNC. Before that was 2.33 and 2.19.
Part number and SW versions are usually marked on the EPROMS. EPROMS do not usually go bad, but it is possible. Defective EPROMS are easily replaced and/or reprogrammed. And of course they can be read out just as easily.
2.6 Monitor
The original monitor is fine when it works, but the design was not very good. By now most of its components are obsolete, but can still be had if one searches. Especially in
The original monitor also generates a lot of heat, some even excessively. The original monitor can be replaced with a modern flat screen monitor. Cheap replacements simply hook up a TV to the TV hook-up socket on NRP53. The better replacements use the original connector on the NCR53 board (D4) and also incorporate a voltage converter in the processing electronics. Currently replacement monitors are still quite expensive.
The TV connector on the NRP53 is even mentioned in some sales brochures:

3. Mechanical
4.0 Software
4.1 V24
For communication between the machine and a computer there was a program available called "V24".
This program allowed the machine programs to be loaded from the computer to the machine, and from the machine to the computer.
This program will only run in a DOS environment. You can emulate a DOS environment even on todays computers, and you can even use an RS232 interface through a USB port.
But no matter what you do, using the V24 program is very tedious and uncomfortable.
It is highly recommended to switch to the program "NC Link", which is available for free on the internet, and which works beautifully.
4.2 DNC
DNC operations are only possible on the D4/C3 with SW level 3.07. This SW comprises of a few chips with different SW and minor HW modifications on the NEP52, as well as a slightly faster processor (there are opinions that say the faster procesor is not mandatory).
To use the DNC function, a program was available from Deckel, which also operated under DOS.
Using DNC on the D4 is painful, because of the DOS environment and because the program can not be interrupted. If an interruption occurs (like tool breakage) the entire program must be restarted.
Other DNC software is available from other vendors.

4.3 SW levels
On the D4/C3 turn to mode 16 and press INFO to display the SW installed on your machine.
The last SW level available for the Dialog 4 was 3.07 which included the DNC function.
On D1 - 3 turn to mode 16 for a direct display.
NRP53 >>>>> http://www.dialog5.com/nrp53.htm
NPP55 >>>>> http://www.dialog5.com/npp55.htm
NPP54 >>>>> http://www.dialog5.com/npp54.htm
NSI56 >>>>> http://www.dialog5.com/nsi56.htm
NCR53 >>>>> http://www.dialog5.com/ncr53.htm
NSP55 >>>>> http://www.dialog5.com/nsp55.htm
NEP52 >>>>> http://www.dialog5.com/nep52.htm