ERROR 816

Er 816
“Collimator move error”

       Displayed on PC: Collimator fails to reach correct position in time

Description
This error occurs if it takes more than 8 s for the collimator plate to move from the 18x24
position to the 24x30 position, or vice versa.
At the two positions, the test point COLL_Pl at CPU board (D801) is high (5V), and in between
it is low (0V). The test point value can also be read by the service program. “Stand tests/Switches” will show all switches, and the one that corresponds to COLL_Pl is named Collimator position 18x24.

Fault elimination, trouble shooting
Switch between 24x30 and 18x24 object tables and check if the collimator plate moves at all.

If it does not move:
- Check if the CPU sends out pulses, COLL_ST test point on D801, if not, replace D801.
- Check if the wing board (D805) receives pulses, test point COLL_ST on D805, if not check cables and connectors between D801 and D805.
- Check voltages on wing board 5V and 14V.
- Check STEP_ENABLE test point on D805, it should be low (0V) when pulses are output to the motor.
- Check if it is at an end position, and the direction is into the end. Direction test point COLL_D at D805 should be low (0V) when moving collimator towards the patient. If something is wrong, check cables and connectors.

If it moves:
- Check if the collimator position 18x24 light switch works as in the description above.
- Check if it moves the whole time of 8 s. If it does but apparently not reaches the other position in time, then something may be in the way that slows the speed down, or the motor may be faulty. In the last case, try changing the motor.
- If the motor stops after just a short time, either the motor or the wing board
(D805) is faulty. Try replacing one of them.

chek variable resistor

Hello my friend ,

What veriable resistor do you mean ?

The one that is used in the ANGULATION ( ROTATION ) ?

Please give me more details about the '' veriable resistor " you mention above !

Thank you very  much in advance .

Regards ,

Kioupis7007