Fuji Frontier 7700 – Guillotine/Cutter Keeps Cycling Continuously After Startup

[reki]

Hello everyone,

I have a problem with the cutter/guillotine on a Fuji Frontier 7700.

After powering on the machine, the guillotine continuously cycles and keeps cutting nonstop. It does not stop or return to standby mode.

What I have checked so far:

• No visible paper jam
• Mechanism seems to move physically
• Suspecting HOME sensor / position sensor
• Also considering possible issue with the driver board or shorted transistor

Has anyone experienced a similar issue on Frontier 7700 / LP7700?
Could this be caused by the HOME sensor, or is it more likely a board/driver problem?

Any help or advice would be greatly appreciated.

Thank you!

[Minilab service]

Cut motor ( DM1 ) connected to J/P258 on printer I/O PCB2 ( J391256 ) . There is motor control circuit. Cut motor ON/OFF signal comes from J/P201 pin 26 ( printer control pcb , J391423 ) . 

Go to output check menu. Then cut motor should stop. If will not - faulty motor control circuit on I/O PCB2 , or faulty printer control pcb ( always is ON ) .

There are two sensors - cut home sensor (  SE8 ) and cut end sensor (  SE9 ) . Sensors connected to J/P261 on I/O PCB2 ( J391256 ) . Sensors works, or not can see on input check menu and output check menu. When sensor opened and closed you should see status changes ( Light or Dark ) .

Fujifilm LP7700 is Noritsu QSS3704F ( not HD model ) . With this model can use old Fuji software, or new software from Noritsu.

[reki]

46 minutes ago, Minilab service said:

Cut motor ( DM1 ) connected to J/P258 on printer I/O PCB2 ( J391256 ) . There is motor control circuit. Cut motor ON/OFF signal comes from J/P201 pin 26 ( printer control pcb , J391423 ) . 

Go to output check menu. Then cut motor should stop. If will not - faulty motor control circuit on I/O PCB2 , or faulty printer control pcb ( always is ON ) .

There are two sensors - cut home sensor (  SE8 ) and cut end sensor (  SE9 ) . Sensors connected to J/P261 on I/O PCB2 ( J391256 ) . Sensors works, or not can see on input check menu and output check menu. When sensor opened and closed you should see status changes ( Light or Dark ) .

Fujifilm LP7700 is Noritsu QSS3704F ( not HD model ) . With this model can use old Fuji software, or new software from Noritsu.

Thank you for the detailed information.

I checked both sensors and they seem to work correctly. With the side cover open I manually blocked/unblocked them using a piece of paper and the sensor status changes correctly (dark/light)

At the beginning, when I completely pull out the cutter unit, the knife does not run continuously.

When I send a print job, the cutter works normally and cuts everything correctly. But at the end of the job the cutter motor does not stop and the knife keeps cycling continuously without stopping.

Maybe this detail can help identify whether the problem is on the I/O PCB2 motor control circuit or the printer control PCB?

[Minilab service]

Cut motor ON/OFF signal is between ground and J/P262 pin 26.
Motor control circuit output is on connector J/P258 contacts ( between pin 1 and pin 2 ) .

Both connetors are on PRINTER I/O PCB2 ( J391256 ) .
If board ON/OFF signal on J/P262 pin 26 works, but on J/P258 contacts you always have 24V then faulty PRINTER I/O PCB2 . 
If doesn't change ON/OFF signal then faulty printer control pcb.

[reki]

21 minutes ago, Minilab service said:

Cut motor ON/OFF signal is between ground and J/P262 pin 26.
Motor control circuit output is on connector J/P258 contacts ( between pin 1 and pin 2 ) .

Both connetors are on PRINTER I/O PCB2 ( J391256 ) .
If board ON/OFF signal on J/P262 pin 26 works, but on J/P258 contacts you always have 24V then faulty PRINTER I/O PCB2 . 
If doesn't change ON/OFF signal then faulty printer control pcb.

I changed the paper to 152, and 10 photos came out perfectly.

With 305 paper, one photo would go, and the cutter would keep turning.

Maybe the guillotine arm has turned and isn't hitting the sensors?

Why do 10x15 cm prints normally come out around 20, but one with 305 paper doesn't?

[Minilab service]

When cut 305 mm width paper need more power. Motor drive circuit heats more. Probably motor drive circuit doesn't work properely.

To say what is wrong need to  know what is on input and output.
If on input is OFF , but cut motor still rotates then faulty motor drive motor.
If on board input always is ON then this signal comes from printer control pcb. Need search what is wrong there.

Only you can see when sensors are opened and when they are closed. Look how they work.

[reki]

15 hours ago, Minilab service said:

When cut 305 mm width paper need more power. Motor drive circuit heats more. Probably motor drive circuit doesn't work properely.

To say what is wrong need to  know what is on input and output.
If on input is OFF , but cut motor still rotates then faulty motor drive motor.
If on board input always is ON then this signal comes from printer control pcb. Need search what is wrong there.

Only you can see when sensors are opened and when they are closed. Look how they work.

Is it possible that we folded the knife incorrectly if the first photo (leader) is fine, but the next one turns out to be 20x15, which is twice as long? This causes the paper to jam because the next rollers don't catch it?

[Minilab service]

Only you can see what works and what doesn't work. When have problems insert bad paper ( fogged, old ) , open printer door, on door sensors put magnets. Then print photos and look what doesn't work.

Software from print control pcb turns on cut motor. On PRINTER I/O PCB2 J/P262 pin 26 ON/OFF signal should change. When level changed cut motor should rotate. When level returns - motor should stop. Initially cutter is on home position ( where is home sensor - SE8 ) . When motor rotates it should reach cut end sensor . Then motor should continue rotate and reach home position. When cutter reached home position then motor should stop.

ON/OFF signal can measure using multimeter. There is low voltage levels ( 0V, or 5V d.c. ) .

If go to output check menu cutter should stop. There you can run cut motor manually. Also can see how work home and end sensors. 

[reki]

1 minute ago, Minilab service said:

Only you can see what works and what doesn't work. When have problems insert bad paper ( fogged, old ) , open printer door, on door sensors put magnets. Then print photos and look what doesn't work.

Software from print control pcb turns on cut motor. On PRINTER I/O PCB2 J/P262 pin 26 ON/OFF signal should change. When level changed cut motor should rotate. When level returns - motor should stop. Initially cutter is on home position ( where is home sensor - SE8 ) . When motor rotates it should reach cut end sensor . Then motor should continue rotate and reach home position. When cutter reached home position then motor should stop.

ON/OFF signal can measure using multimeter. There is low voltage levels ( 0V, or 5V d.c. ) .

If go to output check menu cutter should stop. There you can run cut motor manually. Also can see how work home and end sensors. 

I fixed that by moving the "black moon" that's responsible for covering the end switches.

However, I'm now having a problem with the paper transport.

The paper reaches the end, but the next laser cut doesn't pick it up

What could I have done wrong?

[reki]

The 10x15 format is working, the paper is being fed, but the 20x30 format won't let me grab the roll from the top section

[reki]

4 hours ago, reki said:

The 10x15 format is working, the paper is being fed, but the 20x30 format won't le

t me grab the roll from the top section

It's strange because the first photo (of the paper section) goes well, and the 127 and 152 formats work fine. However, when the 305 and 205 formats appear, there's a problem
The paper won't feed into the next unit. Does anyone have any ideas on where to look for a solution?