SM102-2 P: SSK not working > 2 boards.

Hello. I'm having a problem our machine SM102-2 P (old machine).
The SSK board is working well when we use only 1 board on any slots/boards (original 3 boards/slots).
The board will blink like normal. The problem arise when we start to install back 2 or more boards.
If 2 or more, the all board not blinking. Tried restarted the machine too.
Anyone have this experience before? Please advise.

Thanks.

 

If you have that problem first at all you must check power supply ntk85 . (You have two) Then cable connector between SSR backplane and RER backplane . Then replace SAK2

 

Hi sir
Generally on old SM102s, this problem is almost always a tired NTK85, it is enough for one card to demand a little more current for everything to cut out

this is how i proceed in this type of issue
-Check the voltage with no load no SSK cards
Remove all SSK cards from the rack.
Power on the machine.
Measure voltage directly at the NTK85 output Between +24V and GND mist be between 23.8V to 24.2V If ok proceed to next step. If already <23.5V or unstable NTK85 is defective replace it.
- Check voltage under load with 1 SSK card
Now insert only 1 SSK card.
Start the machine normally then measure voltage again at NTK85 output still between 23.8V to 24.2V, stable.
If OK continue.
- Check voltage with 2 or 3 SSK cards
Now insert 2 SSK cards me
asure again.
observe carefully if Voltage stays stable at 24V Power supply is OK
Voltage drops 22V or lower the Power supply is weak
The SSK LEDs no longer blink the Power supply cannot handle the load or bus issue
If the voltage drops as soon as you insert multiple cards the NTK85 needs to be replaced.
- Visual inspection of NTK85
While the NTK85 units are exposed, do a quick visual check
Bulging or swollen capacitors replace the unit.
Burn marks defective unit.
High pitched noise or whining capacitors are worn out.

Good luck

 

Many thanks all for the information.

 

Did you solve the issue ??

 

The issue is gone. I've changed the NTK85 with a spare because the is a voltage drop (intermitent) and I also unplug all the ribbon cable at the back panel of the SSK and clean them with contact cleaner.

 

Good job be welcome