What went wrong? Help please!

[scnj]

Hello, I'm hoping that this is the right forum to post this type of question!

Here is the problem: I have a large format printer that has a built in chiller. A few days ago we smelled a slight burning smell coming from the machine. We could not pinpoint the issue so we let it continue to run. The next day as it was running we saw a spark from the machine and then smoke. After shutting everything down and opening it up, we found this. (see photos)

Although it just looks like a Current limiter got fried, the service tech came and informed me that they are only able to replace the entire chiller as the electronics are housed inside the chiller unit. Cost is $17k!!

After getting past the initial shock, I let the service tech leave and I took apart the chiller unit and found the parts that were burnt. It looks like the inrush current limiter blew as you can see in the photos, it also burnt up the Contactor next to it.

I ordered replacement parts for the three rail mounted terminal blocks, (2) inrush current limiters, and Contactor din/panel. Basically everything close to where the blown part was located.

My question is, what would have caused this? Should just replacing the parts in question be enough to fix this? Could it just be that the inrush current limiter failed due to age? The printer is in high use every day. I'm hoping that this is the case. But I thought I'd post here to see how the experts weight in and if you would do anything else differently.

Any input is greatly appreciated!

 

[Diver300]

It's very difficult to say what caused that. Inrush limiters are reliable if used correctly, but anything can fail.

I would look at measuring the inrush current, and the steady-state current.

As the contactor is near the inrush limiter, it might be there to short out the inrush limiter a few seconds after start up. I would check if that is the case, and if it is indeed shorting them out correctly.

Most devices that have to have circuits to limit the inrush will have problems if they are started too often.

 

[Western]

My thoughts are that it is certainly possible that they just died from age. I don't see that many used nowadays for some reason. Lots of varistors and plenty of them deteriorate from heat and age.

 

[Externet]

Remote guessing...after decades of experience.
A tranzorb or varistor or surge protector (black disc) near L1 labeled contactor terminal failed tired or because a spike on the electrical mains burned it, ending toasted with time or repeated spikes, disabling traces, solder joints, fuses or other components.
Then the dealer - technician who is more a part swapper than technician saw the easy opportunity of $elling expensive parts for the fat income of the month instead of doing some work repairing it.

A power supply should be very simple to reverse engineer and sketch if its schematic is not available. Many technicians, engineers should be capable of putting back into operation with little effort and cost. Finding one that is not after wringing wallets is another story.

Whatever you do, do not allow the ´technician' to take property of the failed assembly. Contact a knowledgeable person and repair. Chances are it is not a complex repair.

 

[scnj]

Great thank you all for your quick replies. I just got the contactor din/panel.
I though I ordered the exact same one, DIL M9-10 but this one says DIL M9-10-PI
They both show 230v 50/60hz but the new one does not have the openings on the side for the the wires. Instead it looks to be two smaller holes on top to accept the wiring. Will this work or should look for the exact same part? All of the numbers on the side seem to match up.

 

[Diver300]

Electrically, the new one will be fine. If the wires will reach, I suggest you use it.

However, there may me a whole load of messing around and extending wires so it might be easier to get other contractors.

Many companies make similar and interchangeable contractors. It may be easier to go for another brand that looks different but has connectors more similar to your old contractors. As long as the coil voltage is close and the contact ratings are the same or larger than the old ones you’ll be OK.

On the coil voltage, some are rated to 240 V ac and they would be fine. Other common voltages, like 110 or 120 or 380 or 415 V would not work properly.

 

[rjenkinsgb]

The new one uses "Cage clamp" style terminals.

Generally, with that style, you push a small screwdriver in to the square or rectangular hole, and that opens the spring gripper in the paired round terminal hole, so a wire can be inserted or removed.

 

[scnj]

Just wanted to report back and thank everyone who commented. I was able to get the wires to reach the new contactor via cage clamp terminals. Everything is back up and running. Crisis averted. Thank you everyone for helping out!