A little curiosity today. Equipment totally not from my field nor from my times, but perhaps nevertheless worthy of attention - an old triple time relay still remembering the times of the USSR. The whole thing is already built on semiconductors. Time to take a look inside.
On the front panel we have the option to set three separate switching times for the relays. Slightly below we have a diagram showing the internal connection and indicating which screw terminal is the common, normally open and normally closed contact. Let's take a look inside:
Inside we see three separate relays and two control boards. On one of these is a paint-protected potentiometer, presumably for tuning.
What surprises me most, however, is the size of the components. The relays there are nothing like today's modern compact solutions. As a whole, there is additionally a lot more mass, and thus also raw material.
Disassembly progress and designation from plate - C67.102.280:
Disassembly of the circuit board showing the rectifier bridge, large electrolytic capacitor and characteristic resistors. Although the timing itself is mechanical, the counting is already solid-state.
There is no descriptive layer on the board and all tracks are tinned for durability.
Removal of the front panel and separation of the mechanical part:
Removal of relays:
Removal of the counter module:
It is realised on the K176TM1 and K176NE5 integrated circuits. I am puzzled by the component next to the potentiometer - is it a resonator of the time?
I still wanted to check how the time is set, but the disassembly was interrupted by the 2024 flood and the analysis was not completed and the board was lost. However, from what I remember, there were separate contacts for each lead rather than a single resistive path.
I found a similar device on this page: https://dzen.ru/a/X70JlQtK-AFJrFkT
I had originally planned a more detailed presentation with a sketch of the schematic, but the 2024 flood thwarted these plans and the equipment did not survive the cleaning stage. Therefore I would appreciate any additional information if anyone is able to identify the correct operating principle and the roles of the components from inside?
Cool? Ranking DIY Helpful post? Buy me a coffee.
