TTK board capacitor burnout

We had electrical fire smell coming from the center of the console. Opened it up and saw a capacitor on the TTK board (upper part of the BLT) melted and arcing. Put another TTK board in and within 60 seconds, same thing. Called Heidelberg and asked for wiring schematic for the TTK board to find out what specifically that capacitor was used for, was told I would that would never happen. Anyone out there have a better answer?

Thanks,

Peter

 

I can tell you as a technician for the QMDI, there are no board level schematics available. Not even to us. Wiring diagrams yes, you should have one for the machine as they came with them.

There is no reason for them because the complete boards were replaced when damaged, not the individual components on them.

I can tell you the board gets its 48VDC signal power from the GRM board. The 3 phase main power comes from the KVT board.

Something tells me your issue may be the KVT.

 

Theory is that something upstream is shorting or somehow asking for more power than the capacitor can handle. so I am attempting to locate what that capacitor is driving. Isn't the KVT in the opposite direction?

 

The TTK is responsible for taking the control signals from the MRK and converting them to control signals for the KVT which in turn sends power to the motor. The KVT has a Chopper Resistor 15R1 that is supposed to take up the extra energy from the motor to prevent a rise in the intermediate circuit voltage. Admittedly, I am not sure if that can be the problem although the TTK does communicate with the KVT. The only other area to check is the 48VDC, going to the TTK from the GRM.

I can say that anytime we had a problem with either the KVT or the TTK we just replaced the whole assembly.

 

i would be looking at the main motor now, I've seen a couple seize/fail and take out the ttk

 

Thanks Paul, Butch says "you are a very smart guy"! And Roger, we are testing the main motor now.

 

Butch is easily impressed...

 

Hi Paul,

We tested the main drive motor by unhooking the motor and booting up. Got through the entire boot with no damage to the TTK. Then Butch hooked up a replacement motor and booted up again, Bang! Capacitor blown. Then we changed out the KVT fixed the cap on the TTK and rebooted. Got completely through the boot with out blowing the TTK. However now the motor is clicking and the monitor registers a Main Motor Malfunction that won't go away and it won't allow us to inch the press. Butch is now going to pull a complete BLT and MRK from a classic. Butch is asking if the MRK from the classic is compatible with the Pro, and if not is it as simple as swapping the E-Prompt switch. Thanks, Peter

 

Clicking means the fuse is blown on the KVT, it has been awhile so I am reaching here, but I think the fuse is F1, its right by the motor encoder plug on the board.

The MRK board is the same but the software is different. I do not think it is the problem. It only tells the TTK what to do through low voltage signals.

 

I agree

 

I'm glad because I have not seen one of these machines in years...

 

Paul
Just to clarify I agree with your diagnosis of the press also that butch is easily impressed. LOL