Polar 72CS Error|No cut cycle

Hello Everybody,
i have a problem with a Polar 72CS standard cutting machine, Nr. 5451197.
I can't release the cut cycle while pushing the 2 cut buttons.
The machine has a safety bolt. The bolt will not release to cycle the knife down.
The 2 sensors and the coil of the solenoid seems to be O.K.
The hydraulic clamp is also not working while pushing the cut buttons.
On this machine there are no light barriers installed.

Further there is no wiring diagram with this machine to go deeper for that fault.

I would appreciate if there is somebody who can help me with this issue.

 

Hi sir Good day:
Hope you are well.
This is old machine, i will try to give some basic steps, since you do not have schematic Diagram+wiring diagrams
1) The machine has in the from the board # 3 has Yellow Receptacle calle G2: you must measure +24Vdc , if there must be 0.5% of tolerance up and down. if NOT replace it.
2) If the power supply +24Vdc that feed all electronic system control for the push button cutting b28a+b28b, when you close this contacts and Feed the limit switch b.sb(limit switch for Safety bolt), you must measure pin
7.34(board # 7, contact 34 with very carefully, since you can make some short circuit. +24Vdc.
3) If there are Not, so you can make a jumper bridge between plug D 40.7 vs D 40.1 . If When the push button b28a+b you push again +24Vdc must pass and closing the Small relais D1 , you must measure in the 7r2 Test receptacle +24Vdc. See my schematic d that i did prepare for you for easy fix it.
4) This test indicate the limit switch b.sb is faulty or disajustment, adjust it and clean very well and tigh the wires insides to due loose.

 

Hi Sir,
thanks for your reply and your explanations.
In the meantime i noticed following status of the machine.
First i thought i have a problem with a fault contact because the machine was working several cycles until the error appeared again.
Since that 'interruption' the error has an other description.
The safety bolt is now working when i push the two cut buttons, but the cut cycle will still not start.

What i have checked to go through:
- the 2 switches on the backside for the movement position of the knife.
They are O.K. i have no resistance between the contacts.
- For my understanding the hydraulic valve on the hydraulic steering block should be engaged after the safety bolt was released.
On this hydraulic block there is a solenoid with a sensor inside which should engage the valve.

I measure no DC Voltage when i release the cut cycle on the Solenoid.

Maybe you have another idea? An original wiring diagramm of this modell would be a great help.
Beside i will start a new thread for searching a diagramm

Kind regards,
grafische

 

in This kind of polar are many secrets, that they incorporated, and believed they are very complicated
in relation to other models. Some 1) small relais in the board # 7 can be defective 2) you must sure the time with the gear lever with limit swich they are well adjust. The knife will be in the higher point, other wise the knife has that problem in conjuction with the small relais if are defective. Clean very well the Bolt solenoide with graphite ( for LUBE). Must be sure the shaft of Bolt solenoide touch very well the limit switch or sensor,, can be dirty or defective. Try to by pass as I indicate and take his conclusion. Most of the time is the 2 point that i did indicate before.
Let me know. the secret is small relais D1 is close when the +24Vdc go to the push button cutter and then pass to the limit switch( as the schematic diagram provide you) and activate the coil of small relais D1 in board # 7 they activate D2+D3 until the solenoid Activated. otherwise must be defective board # 7. Tight the 2 wires from Solenoid and clean it.