Jump to content

Dead 2475S2 / 2476S - replaced caps but get LED flash on SET push and no relay with on/off


Recommended Posts

My Smartlabs 2475S2 on/off modules and 2476S switches have been dropping like flies over the last few months. No relay click when on/off pressed and the only sign of life is the LED glows slightly and flashes if you hold down the set button.

On 3 separate units, I've replaced the 3 electrolytics in each and checked the diodes but still the same problem. The original small 10uF caps had high ESR and low capacitance values. I get 160v across the main 250v 6.8uF but the lower supply rails (C8?) don't seem to be stable.

Has anyone had similar issues and been able to repair successfully? I was thinking maybe the LNK354GN switcher IC could be faulty but don't want to start randomly replacing ICs if someone has already found another common fault point. I read the datasheet on the LNK354GN  and it says it resets every 650ms when in an overload condition - which seems about the same frequency as the LED flashes when the SET button is held down.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.


×
×
  • Create New...