Most frequent problems with A522
- the picture show you the jumper positions onto the A522 board.
- this could help you to understand a purpose of the jumpers as well to look over entire multi-source .
- What to do in case of broken sense lines on HDI. ( !!! the senses are still active! localy, on P.S. output )
- inseart a 50 pin T-connector ( to be provided by Torino ) between A522 and cable . Output voltages can be measured ( the load is the HDI ! ).
- find the source which output is exactly the set voltage . That one is with no remote senses .
- before the problem , or using another good sense the same type HDI channel , with the same 50 pin T-connector , get number what voltage must be on the output to get a nominal on the HDI ?
- set the voltage .
- adjust the source corresponded trimmers on front pannel to reach the set voltage + 0.1 ... 0.2 V
- power the HDI ON and check the current readings ( are they not exceeding the usual values ? )
- can you readout the HDI now ?
- If you've insearted A522 during the SY527 was ON , the A522 will respond after a restart the SY527 ,
but no one source can be switched ON .
- the 2A fuse has been burned .
- dismount black box ( Pulsewidth modulated Switching P.S. ) taking out four screws .
- change the 2A fuse ( to be provided by CAEN/Torino ) .
- try the A522 again .
- You switch a sources ON , but no one is powered. No warning on a STATUS column. The dissipator
(near transformers) is cold.
- check +73 V arrived from Pulsewidth modulated Switching P.S.
- check a 33KHz clock on digital board : R98 , Q2 , 14 of U37 .
- find a 66KHz on 4 of U37, or 1 of U36. If not presented , change the IC's : CD4046 , CD4024 .
- follow the 66KHz clock on inter connection board till two MOSFETs ; the path - R33 , 1 and 7 of U10 , 1 and 7 of U11 , C7 and C9 , R8 and R11 , Q3 and Q4 . Find a broken component .
- If you find a one source of A522 doesn't work properly :
- the most frequent : some IC (digital board) is turned out of a socket - it touched a neighbouring A522 while the module was insearted .
- connect a dummy load , try the source , remember the problem .
- take the A522 out from SY527 , look carefully : may be a pin through connector which link up
Low Voltage Board , InterConnection Board and Mother Board , is not insearted properly ? There are
a spacer-nuts for that ( to be provided by CAEN ) . Implement the nut or press all boards together . Try the A522 again .
- unscrew two black dissipators , find the source pcb and exchange with
another one ( all of them are equivalent ) it help to find the pcb
- try the A522 again , the problem still remains ? or has moved to exchanged source ? If second , you have found broken pcb . If first , :
- check ( visually and with ohmmeter ) a jumpers , 50 pin connector , the source transistor TIP122 , LM317 , relay and an outputs of two transformers .
- if even that hasn't threw a light on the problem , the mother board ( digital control ) is guilty : try to change a some integrated circuits (opto-couples , op-amps ) and PAL ( to be provided by CAEN )
- when a group of channels has been switched off by interlock , the status is OFF for all channels , but you are failed pressing "1" to get power back because a register remains "1" .
- You have to press "0" and then "1" .
- In general , you have to press "0" as many times as "1" have been pressed .
- Unknown password: main menu contains 7 items and password is required.
- open front panel; two DIP switches - in down position to bypass the password; SY527 - ON; main menu -> Protections -> Change password -> "enter old password" - just return -> enter new password twice -> Disable password -> Quit
- two DIP switches back; SY527 - ON; main menu contains 10, either 9 items; Password is not required and known by you.
- SY527 reboots suddenly!
- The explanation: within H.S.CAENET chain there are more than one SY527
which status is MASTER. SY527 becomes to be a master each time it's connected
with a RS232 terminal. The status can be changed with full shut down only.
Important:there is no software code/command to start rebooting!
- just switch all SY527s off and back them on.
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